tag:theconversation.com,2011:/africa/topics/soil-erosion-2796/articlesSoil erosion – The Conversation2023-06-26T04:56:38Ztag:theconversation.com,2011:article/2071552023-06-26T04:56:38Z2023-06-26T04:56:38ZSoil erosion is filling vital inland river waterholes, putting the squeeze on fish, turtles and crayfish<figure><img src="https://images.theconversation.com/files/531528/original/file-20230613-26-wznt2l.JPG?ixlib=rb-1.1.0&rect=4%2C9%2C3058%2C1784&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">John Tibby</span>, <span class="license">Author provided</span></span></figcaption></figure><p>During droughts, Australia’s inland rivers dry up, leaving waterholes as the only wet places in a parched landscape. Fish, turtles, crayfish and other aquatic animals retreat to these vital refuges. </p>
<p>But our research, <a href="https://doi.org/10.1071/MF23016">published today</a>, reveals these waterholes are in danger of filling up with eroded soil from farms. This is putting a big squeeze on life in the river. </p>
<p>When drought breaks, the water flooding into the river carries soil along with it. In theory, soil deposited in waterholes could be flushed out again by large floods.</p>
<p><a href="https://www.sciencedirect.com/science/article/abs/pii/0169555X94900523">Studies in the 1990s</a> suggested as long as floods continued to occur, waterholes would maintain a natural balance of sediment. But these studies focused on the Cooper Creek, in the Kati Thanda (Lake Eyre) Basin, where waterholes have a sandy base underlying clay-dominated soil that can be easily washed out again. Many Australian rivers are different. So what happens elsewhere?</p>
<p>Our new research investigated waterhole infilling in the Moonie River, in the northern part of the Murray Darling-Basin. The Moonie catchment has experienced extensive clearing of native vegetation for sheep and cattle grazing. Unlike some neighbouring catchments, the upper and middle portions of the river have minimal water extraction and so their flow patterns are relatively “natural”. It’s a true “dryland river”, flowing only after infrequent rain events. During long periods with no flow, waterholes become the only remaining wet habitats for aquatic animals to survive.</p>
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<a href="https://images.theconversation.com/files/531582/original/file-20230613-22-m9x1lj.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A photograph of Moonie River showing bare banks and soil erosion" src="https://images.theconversation.com/files/531582/original/file-20230613-22-m9x1lj.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/531582/original/file-20230613-22-m9x1lj.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/531582/original/file-20230613-22-m9x1lj.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/531582/original/file-20230613-22-m9x1lj.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/531582/original/file-20230613-22-m9x1lj.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/531582/original/file-20230613-22-m9x1lj.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/531582/original/file-20230613-22-m9x1lj.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">Moonie River’s bare banks suffer from erosion. Much of the catchment has also been cleared for grazing.</span>
<span class="attribution"><span class="source">John Tibby</span></span>
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<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/australias-inland-rivers-are-the-pulse-of-the-outback-by-2070-theyll-be-unrecognisable-136492">Australia’s inland rivers are the pulse of the outback. By 2070, they’ll be unrecognisable</a>
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<h2>Poking at sediment to understand waterholes</h2>
<p>Waterholes in the Moonie River can be more than 5 kilometres long, up to 5 metres deep, and teeming with life. Kingfishers, whistling kites and parrots create a symphony of sound while fish occasionally break the surface of the murky water. </p>
<p>We studied three of the deepest waterholes in the Moonie River, as they are the ones that <a href="https://www.frontiersin.org/articles/10.3389/fenvs.2021.671556/full">last longest in droughts</a>. Our initial method was simple. Using metal rods, we probed the soil’s depth at evenly spaced points along the waterholes. Our first survey revealed all three waterholes had accumulated at least a metre of soil, with one site showing more than 2.5 metres of infilling, significantly reducing its depth.</p>
<p>To determine the rate of sediment accumulation, we used radiocarbon dating. This technique is commonly used for dating objects thousands of years old such as the <a href="https://www.nma.gov.au/defining-moments/resources/mungo-lady">Lake Mungo skeletons</a>. However, nuclear weapons testing in the 1950s introduced new radioactive material including radiocarbon into the atmosphere worldwide. By analysing radiocarbon in the Moonie River sediments, we could estimate their age. </p>
<p>Our sediment dating revealed that, in places, more than two metres of soil had filled the deepest waterholes <a href="https://doi.org/10.1071/MF23016">since the 1950s</a>. Before European occupation, it would have taken thousands of years to deposit this much soil. Our research suggests sediment infilling also sped up over the past few decades.</p>
<p>The accumulated soil reduces the waterholes’ depth, preventing them from holding water for as long as they used to during droughts. Our modelling indicated this reduction has shortened the duration waterholes can hold water by almost a year at some sites, bringing them dangerously close to complete drying during the longest droughts.</p>
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<a href="https://images.theconversation.com/files/533943/original/file-20230626-5608-3zt1z7.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A cut-away graphic showing comparing the depth of waterholes before and after European settlement" src="https://images.theconversation.com/files/533943/original/file-20230626-5608-3zt1z7.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/533943/original/file-20230626-5608-3zt1z7.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=276&fit=crop&dpr=1 600w, https://images.theconversation.com/files/533943/original/file-20230626-5608-3zt1z7.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=276&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/533943/original/file-20230626-5608-3zt1z7.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=276&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/533943/original/file-20230626-5608-3zt1z7.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=347&fit=crop&dpr=1 754w, https://images.theconversation.com/files/533943/original/file-20230626-5608-3zt1z7.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=347&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/533943/original/file-20230626-5608-3zt1z7.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=347&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">Waterholes were much deeper before European settlement.</span>
<span class="attribution"><a class="source" href="https://ian.umces.edu/media-library/">Sara Clifford, using resources from the Integration and Application Network</a>, <span class="license">Author provided</span></span>
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<h2>Do floods remove soil from waterholes?</h2>
<p>However, two significant questions remained: does sediment get removed after a large flood? And if it does, does material from upstream simply get dumped downstream? To answer these questions, we needed some luck and a knowledge of cocktails.</p>
<p>In 2010 and 2011, the Moonie River experienced two <a href="https://www.abc.net.au/news/2011-01-04/flood-hit-st-george-evacuates-residents/1893662">very large floods</a>. This gave us the perfect opportunity to find answers. We repeated our waterhole surveys and found even after big floods, there was still a minimum of 1 metre of sediment across most of the bottom of these waterholes, with much deeper sediment in places.</p>
<p>The missing piece of our puzzle was to determine whether the sediments were mixed together, like a margarita, and deposited by a single flood, or if they were layered, resembling a B52 cocktail (another connection to nuclear bomb testing). </p>
<p>To unravel this, we examined how the sediment had changed since before the floods. We observed distinct layers, like those in a B52 cocktail, indicating the sediments had been deposited over a series of flows and floods since the 1950s, rather than solely after individual floods.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/we-helped-fill-a-major-climate-change-knowledge-gap-thanks-to-130-000-year-old-sediment-in-sydney-lakes-187784">We helped fill a major climate change knowledge gap, thanks to 130,000-year-old sediment in Sydney lakes</a>
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<h2>How can we solve this problem?</h2>
<p>We need to address the imbalance between eroded soil supply and the river’s capacity to transport sediment downstream. </p>
<p>In the Moonie River, water extraction for human use is minimal, so the problem is unlikely to lie with the river’s flow regime. The main culprit is an increased supply of sediment.</p>
<p>That means the solution lies in better catchment soil management. We need to stop so much soil washing into the Moonie River. This requires further research to find the main sources of soil that fills waterholes. Then determine the most effective ways to prevent erosion and reduce the amount of soil entering the river. This approach also helps preserve precious soils on agricultural land. In some exceptional cases, more extensive engineering solutions may be necessary to restore waterholes.</p>
<p>Given climate change projections for more frequent and longer droughts in the region, taking action to restore and preserve the function of waterholes in dryland rivers like the Moonie becomes increasingly crucial. These actions are essential for safeguarding the diverse aquatic animal life and the people that depend on waterholes for survival during droughts.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/its-official-the-murray-darling-basin-plan-hasnt-met-its-promise-to-our-precious-rivers-so-where-to-now-188074">It's official: the Murray-Darling Basin Plan hasn't met its promise to our precious rivers. So where to now?</a>
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</em>
</p>
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<img src="https://counter.theconversation.com/content/207155/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>John Tibby receives funding from the Australian Research Council, The Australian Nuclear Science and Technology Organisation, the Queensland and South Australian Governments. This research was partially funded by the Queensland Government.</span></em></p><p class="fine-print"><em><span>Jonathan Marshall works for the Queensland Department of Environment and Science who partially funded this research. </span></em></p>Australia’s beloved billabongs and waterholes are in danger of filling up with eroded soil from farms, leaving little room for the aquatic animals that depend on these vital drought refuges.John Tibby, Associate Professor in Environmental Change, University of AdelaideJonathan Marshall, Adjunct Senior Research Fellow in the Australian Rivers Institute, Griffith UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1921952022-11-14T18:53:05Z2022-11-14T18:53:05ZRestoring Mayotte’s lagoon: when a newly born volcano meets human resilience<figure><img src="https://images.theconversation.com/files/494711/original/file-20221110-25-4vo9et.jpg?ixlib=rb-1.1.0&rect=0%2C15%2C2048%2C1263&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Mayotte's surrounding coral reef is made up of three different structures more than 350 kilometers long. The lagoon they form is threatened by climate change and erosion. </span> <span class="attribution"><a class="source" href="https://commons.wikimedia.org/w/index.php?curid=77558219">Axelspace </a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span></figcaption></figure><p>One of France’s five overseas departments, Mayotte is the southernmost island of the Comoros Archipelago, located Indian ocean between Madagascar and the African mainland. The island is the centrepiece of a coral-reef structure that was created over hundreds of thousands of years through volcanic episodes, subsidence and sea-level shifts. Made up of three different structures more than 350 kilometres long, the reef encloses a lagoon with a surface area of 1,100 square kilometres that shelters an opulent biodiversity that includes 2,300 known living species.</p>
<p>One of just ten such coral-reef systems on Earth, Mayotte lagoon was classified as a marine natural park in 2010, and the government has long hoped that it would be <a href="https://outremers360.com/planete/mayotte-vise-lunesco">added to the list of UNESCO World Heritage sites</a>.</p>
<h2>Birth of a giant</h2>
<p>On May 10, 2018, however, an event took place that no one could have predicted: 50 kilometres off Mayotte’s east coast, an underwater volcano was born. The natural phenomena that underlay the volcano’s birth and the chain of events that it has set off have forever altered the undersea landscape and the island itself, and will continue to do so for millennia.</p>
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<a href="https://images.theconversation.com/files/494698/original/file-20221110-23-8dqi79.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/494698/original/file-20221110-23-8dqi79.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/494698/original/file-20221110-23-8dqi79.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=171&fit=crop&dpr=1 600w, https://images.theconversation.com/files/494698/original/file-20221110-23-8dqi79.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=171&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/494698/original/file-20221110-23-8dqi79.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=171&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/494698/original/file-20221110-23-8dqi79.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=215&fit=crop&dpr=1 754w, https://images.theconversation.com/files/494698/original/file-20221110-23-8dqi79.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=215&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/494698/original/file-20221110-23-8dqi79.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=215&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">Left: 2014, before new volcano’s birth. Right: 2019, after its discovery.</span>
<span class="attribution"><span class="source">BGRM</span>, <span class="license">Author provided</span></span>
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<p>As the volcano’s growth continued, scientists recorded 800 micro-tremors that occurred several times a day over three weeks. From May 2018 to June 2019, a <a href="https://archimer.ifremer.fr/doc/00632/74401/74104.pdf">series of 32 earthquakes</a> of 5 or more on the Richter scale struck the island. In its short life, the volcano has already ejected <a href="https://www.brgm.fr/en/news/press-release/mayotte-volcano-largest-underwater-eruption-ever-documented">more than 5 km³ of lava</a>, by far the most ever observed, transforming the underwater landscape.</p>
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<a href="https://images.theconversation.com/files/494700/original/file-20221110-21-qh9jz8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/494700/original/file-20221110-21-qh9jz8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/494700/original/file-20221110-21-qh9jz8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=359&fit=crop&dpr=1 600w, https://images.theconversation.com/files/494700/original/file-20221110-21-qh9jz8.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=359&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/494700/original/file-20221110-21-qh9jz8.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=359&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/494700/original/file-20221110-21-qh9jz8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=451&fit=crop&dpr=1 754w, https://images.theconversation.com/files/494700/original/file-20221110-21-qh9jz8.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=451&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/494700/original/file-20221110-21-qh9jz8.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=451&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">In 2018 and 2019, a swarm of earthquakes took place 15 kilometres to the east of Mayotte.</span>
<span class="attribution"><span class="source">BGRM</span>, <span class="license">Author provided</span></span>
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<p>The volcano’s growth will continue for millennia, as it’s part of a natural cycle of island building, destruction and rebuilding. Indeed, just 12,000 years ago, Mayotte was <a href="https://www.mayottehebdo.com/actualite/dossier/il-y-a-12-000-ans-mayotte-etait-cinq-fois-plus-grande/">five times larger than it is today</a>.</p>
<p>While Mayotte’s subsidence is natural, since 2018 it has witnessed the equivalent of a sprint in geologic time – in just four years, the island has moved 20 centimetres to the east and dropped by 15 centimetres.</p>
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<span class="caption">Subsidence of Mayotte in 2019, just a year after the volcano’s emergence.</span>
<span class="attribution"><span class="source">BGRM</span>, <span class="license">Author provided</span></span>
</figcaption>
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<p>The volcano’s birth triggered a series of natural disasters that have been exacerbated by the island’s natural geography and ongoing climate change. Mahorans have long lived with the rainy season, known as <em>Kashkazi</em>, but a series of torrential storms have caused landslides, significant erosion and accelerated coastal retreat. All have tested Mahorans’ resilience and raised questions about how they can best adapt to the changing world around them.</p>
<p>The volcano also disrupted the island’s political, economic and social order. Mayotte has been a French department since 2011 and a special territory of the European Union since 2014, and until the volcano’s birth, its <a href="https://www.mayotte.gouv.fr/content/download/5164/43644/file/Mayotte%202025%20Une%20ambition%20pour%20la%20R%C3%A9publique%20-%20document%20strat%C3%A9gique.pdf">2025 roadmap</a> pointed toward the need for more effective institutions, improved education, development, health care and housing, and sustainable management of natural resources, in that order. After 2018, managing the environmental situation became top priority.</p>
<h2>Accelerating erosion</h2>
<p>During Mayotte’s monsoon season, rain naturally causes erosion, and the soil released is carried into the sea as silt. With the volcano’s eruption and associated swarm of earthquakes, intensifying rains and poor land management have caused erosion to rise. Forty years ago, 5,000 tons of sediment was released annually; by 2018, the rate was 20,000 tons per year, an eightfold increase. The end result is a vast flow of soil into the lagoon.</p>
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<figcaption>
<span class="caption">Increasing rains and poor land-management techniques have led to a dramatic increase in siltation of the lagoon.</span>
<span class="attribution"><span class="source">BGRM</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>For scientists, the volcano’s birth was <a href="https://leblob.fr/en/mayotte-birth-underwater-volcano">one of the first that could be witnessed first-hand</a>, with many more research missions set to enrich scientific databases in the coming decades. One of the most important is <a href="https://www.brgm.fr/en/reference-completed-project/leselam-action-against-soil-erosion-lagoon-siltation-mayotte">LESELAM</a>, which was launched by the BRGM in 2018. Its aim is to better understand the phenomenon of erosion and siltation of Mayotte lagoon, and so be able to better combat it.</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/494703/original/file-20221110-16-nqqly2.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/494703/original/file-20221110-16-nqqly2.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/494703/original/file-20221110-16-nqqly2.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=848&fit=crop&dpr=1 600w, https://images.theconversation.com/files/494703/original/file-20221110-16-nqqly2.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=848&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/494703/original/file-20221110-16-nqqly2.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=848&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/494703/original/file-20221110-16-nqqly2.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1066&fit=crop&dpr=1 754w, https://images.theconversation.com/files/494703/original/file-20221110-16-nqqly2.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1066&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/494703/original/file-20221110-16-nqqly2.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1066&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Erosive basins and annual sedimentation flux (ton/year) in 2018.</span>
<span class="attribution"><a class="source" href="https://www.brgm.fr/en/reference-completed-project/leselam-action-against-soil-erosion-lagoon-siltation-mayotte">BGRM</a>, <span class="license">Author provided</span></span>
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<p>Mayotte is densely populated, and humans have long transformed its topography to facilitate agriculture and livestock ranching. The combination of the island’s volcanic soil, steep slopes, and “slash and burn” farming techniques have left behind many deforested areas known as <a href="https://fr.wikipedia.org/wiki/Padza"><em>padzas</em></a>. With the rise in the island’s population, the uncontrolled growth of shantytowns has contributed increasing amounts of urban runoff that pollutes the lagoon.</p>
<p>Today, scientists and associations are working to raise awareness on the importance of environmental conservation. <a href="https://enrd.ec.europa.eu/projects-practice/fighting-against-soil-erosion-mayotte-leselam_en">Stakeholder collaborations advance</a> but require continued effort. Given the immense challenges, initial enthusiasm can suffer when quick results aren’t obtained.</p>
<p>In 2021 France declared Mayotte to be suffering from a <a href="https://www.legifrance.gouv.fr/jorf/id/JORFTEXT000044289624">natural disaster</a>, but such statements are no longer sufficient. What is needed is bringing international attention to the environmental crisis that is taking place on Mayotte. To revive the island’s economy, raise hope among the population, and preserve this magnificent island, the following actions were carried out:</p>
<ul>
<li><p><strong>Researching</strong>. On 27 January 2022, an international conference detailed the significant risks that Mayotte faces in the coming years due to global warming and emphasised the importance of nature conservation.</p></li>
<li><p><strong>Campaigning</strong>. On 18 May 2022, an international campaign was launched protect and restore Mayotte lagoon and advocate for change and push for action, the lagoon desilting project is registered in this environmental protection campaign.</p></li>
<li><p><strong>Economic planning</strong>. Restoring the lagoon isn’t just a matter of removing the silt, but also establishing a circular-economy model to reemploy it. On an island where the unemployment rate is 30%, creating green jobs is a high priority. Salt extracted from the silt could be marketed, while the salt-free earth could be transformed into building material, supporting an existing economic sector and reducing the importation of building materials. With the lagoon’s health restored, green tourism would serve as a channel for sustainable economic growth.</p></li>
<li><p><strong>Educating</strong>. First, while the volcano’s birth of the coast of Mayotte upended the island’s plan to have the lagoon inscribed as an endangered <a href="https://documentation.outre-mer.gouv.fr/Record.htm?idlist=1&record=19142156124919603389">UNESCO World Heritage Site</a> in Danger list. Second, the desilting project should be registered on the 2022-2025 strategic plan of the <a href="https://icriforum.org/cordap-strategic-plan-2022-2025/">Coral Research and Development Platform</a>.</p></li>
</ul>
<p>The 2018 eruption of the volcano off the coast of Mayotte and the chain of natural disasters that it set off have made it crystal clear that the island’s coral reefs, lagoon and mangroves aren’t just natural gifts to be enjoyed. It is urgent for them to be protected, and so safeguard for future generations the rich biodiversity, ecosystem services, coastline protection, and natural beauty that they provide.</p>
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<img alt="" src="https://images.theconversation.com/files/485372/original/file-20220919-20-pguqfq.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/485372/original/file-20220919-20-pguqfq.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=305&fit=crop&dpr=1 600w, https://images.theconversation.com/files/485372/original/file-20220919-20-pguqfq.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=305&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/485372/original/file-20220919-20-pguqfq.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=305&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/485372/original/file-20220919-20-pguqfq.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=383&fit=crop&dpr=1 754w, https://images.theconversation.com/files/485372/original/file-20220919-20-pguqfq.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=383&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/485372/original/file-20220919-20-pguqfq.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=383&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<p><em><a href="https://whc.unesco.org/en/next50/">50th anniversary of the World Heritage Convention</a> (16 November 2022): World Heritage as a source of resilience, humanity and innovation.</em></p><img src="https://counter.theconversation.com/content/192195/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Noro Ravoavahy est membre de l'Alliance HQE-GBC France. </span></em></p>Mayotte is no exception to the adage “small islands, big problems”. A newly born volcano combined with poor land management and accelerating climate change has put its fabled lagoon at risk.Noro Ravoavahy, Architecte, Labex AE&CC, Ecole Nationale Supérieure d’Architecture de Grenoble, Conservatoire national des arts et métiers (CNAM)Licensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1887652022-08-16T15:37:25Z2022-08-16T15:37:25ZDrought: five ways to stop heavy rains washing away parched soil<figure><img src="https://images.theconversation.com/files/479391/original/file-20220816-18-kmctp8.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C3264%2C1836&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/mud-flowing-water-reach-pond-swamp-749912869">Sup10mah/Shutterstock</a></span></figcaption></figure><p>When William Blake described England’s “green and pleasant land” in his poem Jerusalem, he was actually writing during a prolonged drought. Two centuries later, much of Europe is withering under successive heatwaves amid one of the most extreme droughts ever recorded. </p>
<p>The <a href="https://news.sky.com/story/uk-heatwave-britains-green-landscapes-turn-brown-as-river-flows-drop-12669994">latest satellite image</a> of England captured by Nasa shows not a green and pleasant land but one which is brown and parched. Under all that dry vegetation is sun-baked, dusty and desiccated soil.</p>
<p>Heavy rain and thundery showers are now <a href="https://www.metoffice.gov.uk/about-us/press-office/news/weather-and-climate/2022/days-of-thunder-ahead-for-some">forecast</a> for much of the UK. No doubt the promise of a good downpour will please farmers, for whom the drought has been particularly punishing. Bizarrely though, heavy rain may not be what their thirsty soil <a href="https://theconversation.com/drought-heavy-rain-now-might-be-a-serious-problem-for-the-uks-parched-landscape-188666">needs right now</a>. </p>
<p>A soil normally acts like a sponge which soaks up moisture when it rains. Having been baked for weeks by intense heat with little respite, soil surfaces have hardened. </p>
<p>As a result, the soil’s infiltration capacity (the maximum rate at which soils can absorb moisture) has diminished. If rain falls at such an intensity that this rate is exceeded, the water will run off the soil surface, potentially triggering flash floods and other hazards downslope. </p>
<hr>
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Read more:
<a href="https://theconversation.com/drought-heavy-rain-now-might-be-a-serious-problem-for-the-uks-parched-landscape-188666">Drought: heavy rain now might be a serious problem for the UK's parched landscape</a>
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<p>When heavy rain falls, tonnes of soil can be eroded into the flow and rushed out of farm gates. There, it is washed into rivers, and spat out to sea in a brown plume that can occasionally be seen from space. </p>
<p>Likewise, flash floods can leave thousands of households with thick carpets of sand, silt and clay. Cleaning up after extreme rainfall can drain wallets very quickly, but there is a larger and longer-term cost. </p>
<p><a href="https://theconversation.com/soil-is-our-best-ally-in-the-fight-against-climate-change-but-were-fast-running-out-of-it-128166">Soil erosion is a major threat</a> to the resilience of the environment. Proactive measures to curb erosion are essential to ensure soils continue supporting food production, sustaining habitats and biodiversity, cycling nutrients and safely storing the carbon fuelling climate change. </p>
<p>Here are five options for preventing soil running off the land. </p>
<figure class="align-center ">
<img alt="Green pea pods on a bush." src="https://images.theconversation.com/files/479387/original/file-20220816-22-4evxl0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/479387/original/file-20220816-22-4evxl0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/479387/original/file-20220816-22-4evxl0.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/479387/original/file-20220816-22-4evxl0.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/479387/original/file-20220816-22-4evxl0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/479387/original/file-20220816-22-4evxl0.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/479387/original/file-20220816-22-4evxl0.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Planting legumes between crops can restore nitrogen to the soil.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/young-green-peas-pod-on-bush-2007986741">Igor Bastrakov/Shutterstock</a></span>
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<h2>1. Don’t leave soils bare</h2>
<p>A bare soil is particularly vulnerable to erosion. Extreme heat can make some harvests come early, leaving soils bare for longer. Farmers can grow cover crops such as brassicas, legumes and grasses to protect soils from being exposed between periods of crop production.</p>
<p>As well as shielding the soil from rain splash, <a href="https://bsssjournals.onlinelibrary.wiley.com/doi/full/10.1111/ejss.13147">some cover crops</a> can suppress weeds and fungal diseases, replenish carbon and offer food and habitat to wildlife.</p>
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<em>
<strong>
Read more:
<a href="https://theconversation.com/why-the-humble-legume-could-be-the-answer-to-europes-fertiliser-addiction-159067">Why the humble legume could be the answer to Europe's fertiliser addiction</a>
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<figure class="align-center ">
<img alt="Rows of green, leafy plants separated by wood-strewn soil." src="https://images.theconversation.com/files/479388/original/file-20220816-8415-oq2vva.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/479388/original/file-20220816-8415-oq2vva.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=397&fit=crop&dpr=1 600w, https://images.theconversation.com/files/479388/original/file-20220816-8415-oq2vva.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=397&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/479388/original/file-20220816-8415-oq2vva.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=397&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/479388/original/file-20220816-8415-oq2vva.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=499&fit=crop&dpr=1 754w, https://images.theconversation.com/files/479388/original/file-20220816-8415-oq2vva.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=499&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/479388/original/file-20220816-8415-oq2vva.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=499&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Soybeans grown without tilling the soil.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/soybeans-were-notill-argentina-795513256">Helga_foto/Shutterstock</a></span>
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<h2>2. Adapt tillage practices</h2>
<p>Soil tillage (digging, stirring and overturning it) is one of the most practised methods of preparing the land for growing crops. But tilling the soil too vigorously can damage its internal structure. </p>
<p>A healthy soil has a continuous network of pores and channels capable of storing and transporting air and water. Lining this network are mineral and organic aggregates. Maintaining the soil’s structure is vital, not only for bolstering its resistance to erosion, but for enhancing how much water can infiltrate it.</p>
<p>Shifting towards less intensive tillage practices – reduced or zero tillage farming – has been shown to be <a href="https://iopscience.iop.org/article/10.1088/1748-9326/aba2fd/meta">effective</a> at curbing soil erosion. Ploughing across slopes rather than down them can reduce it even further.</p>
<h2>3. Watch out for overgrazing</h2>
<p>Grazing livestock like cattle can maintain grassland habitats and support native wildlife, but overgrazing can be a <a href="https://www.worldwildlife.org/threats/soil-erosion-and-degradation">problem</a>. If vegetation is stripped from the land faster than it can naturally recover, soils are left bare and prone to erosion. </p>
<p>Overgrazing can also compact the soil, making it less effective at soaking up moisture and increasing the likelihood that water will run off the surface. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/farm-vehicles-now-weigh-almost-as-much-as-heaviest-dinosaurs-heres-why-thats-a-problem-182992">Farm vehicles now weigh almost as much as heaviest dinosaurs – here’s why that’s a problem</a>
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<figure class="align-center ">
<img alt="A hillside with flat terraces." src="https://images.theconversation.com/files/479386/original/file-20220816-1633-wpw8xu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/479386/original/file-20220816-1633-wpw8xu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/479386/original/file-20220816-1633-wpw8xu.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/479386/original/file-20220816-1633-wpw8xu.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/479386/original/file-20220816-1633-wpw8xu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/479386/original/file-20220816-1633-wpw8xu.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/479386/original/file-20220816-1633-wpw8xu.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">A terraced rice paddy field in northern Vietnam.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/terraced-rice-paddy-field-landscape-mu-1914393187">Southtownboy Studio/Shutterstock</a></span>
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<h2>4. Consider terracing steep slopes</h2>
<p>Steep slopes funnel water downhill fast. Building a series of level steps into the slope where food can be grown, a practice known as terracing, is an effective engineering solution.</p>
<p>Hillslope terracing has been adopted by farmers for millennia, and can be particularly good at reducing water runoff and sediment erosion, especially if regularly maintained. Levelling the slope can also help water infiltrate the soil and increase how much water it can hold. </p>
<figure class="align-center ">
<img alt="A strip of wildflowers between rows of vines." src="https://images.theconversation.com/files/479383/original/file-20220816-21-xhzq0n.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/479383/original/file-20220816-21-xhzq0n.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=401&fit=crop&dpr=1 600w, https://images.theconversation.com/files/479383/original/file-20220816-21-xhzq0n.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=401&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/479383/original/file-20220816-21-xhzq0n.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=401&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/479383/original/file-20220816-21-xhzq0n.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/479383/original/file-20220816-21-xhzq0n.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/479383/original/file-20220816-21-xhzq0n.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Buffer strips can be a nectar buffet for pollinating bugs.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/green-seeded-cover-crop-vineyard-row-1924241822">Digikluk/Shutterstock</a></span>
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</figure>
<h2>5. Grow a buffer strip</h2>
<p>For fields bordering rivers and streams, planting buffer strips of vegetation on the boundary with the watercourse can <a href="https://bsssjournals.onlinelibrary.wiley.com/doi/full/10.1111/sum.12057?casa_token=IU50b-84leYAAAAA%3AJf_kryjB1VK2ZHMWHROgHB7cILqSV3axI1bng381QK6UJhddgbGUYexNQC2Jz_IweLhFc8uZFkIWDw">offer multiple benefits</a> beyond reducing soil erosion. </p>
<p>Comprised of grass and shrubs, buffer strips increase the roughness of the land which slows the water running off it. Planting trees in buffer strips can help stabilise riverbanks, shade livestock and reduce the runoff of agricultural chemicals into rivers. As well as combating soil erosion, buffer strips feed and shelter pollinating insects, enriching a farm’s biodiversity.</p>
<h2>Be proactive not reactive</h2>
<p>It only takes a second to open an umbrella and protect yourself from a downpour. Protecting soil from erosion demands more proactive measures. </p>
<p>These five recommendations can build a soil’s resistance to erosion, particularly during the spells of heavy rain which often follow heatwaves. If implemented and maintained, these strategies can have lasting additional benefits for soil fertility, biodiversity and slowing climate change.</p><img src="https://counter.theconversation.com/content/188765/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Dan Evans has received funding from UK Research and Innovation (UKRI). </span></em></p>Storms and flash floods often follow a heatwave.Dan Evans, 75th Anniversary Research Fellow, Soil and Agrifood Institute, Cranfield UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1731902021-12-10T14:36:33Z2021-12-10T14:36:33ZBare winter fields to disappear as part of new plan for healthy greener countryside<figure><img src="https://images.theconversation.com/files/436748/original/file-20211209-17-cn9oqf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Fotokostic/Shutterstock</span></span></figcaption></figure><p>Soil is one of the world’s most precious resources, but is often overlooked. The soil does many important tasks. It provides food and energy, keeps water clean, acts as <a href="https://theconversation.com/france-has-a-great-plan-for-its-soil-and-its-not-just-about-wine-47335">a place to store carbon</a> in the fight against climate change, and maintains biodiversity. </p>
<p>But some modern farming and countryside management practices have been <a href="https://www.shui-eu.org/blog-1/">degrading our soil</a>, causing <a href="https://doi.org/10.1016/j.geoderma.2020.114378">erosion</a> and causing other issues in the surrounding landscape.</p>
<p>Now soil is at the centre of a recently announced UK government policy that will pay farmers to improve the environment by growing plants in fields through winter. It could transform how some of England’s countryside looks in the winter months and may lead to a more sustainable future for England’s agriculture.</p>
<p>The <a href="https://www.gov.uk/government/publications/sustainable-farming-incentive-how-the-scheme-will-work-in-2022/sustainable-farming-incentive-how-the-scheme-will-work-in-2022">Sustainable Farming Incentive</a> will replace existing payments that were part of the European Union’s Common Agricultural Policy.</p>
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<strong>
Read more:
<a href="https://theconversation.com/restoring-soil-can-help-address-climate-change-121733">Restoring soil can help address climate change</a>
</strong>
</em>
</p>
<hr>
<p>The new policy aims to establish new standards for arable and horticultural soils (grassland and moorland standards were also published). While the policy, due to be rolled out in 2022, is light on detail, the fact that these initial standards aim to promote soil health is a promising step towards providing and securing these essential ecosystem services on which society relies.</p>
<h2>Changing countryside</h2>
<p>The plans to encourage the planting of more winter crops will mean that visitors will see legumes such as vetch and grasses such as rye, sometimes planted together. This “cover” is designed to protect the soil from erosion caused by winter rains falling on bare soil by ensuring early establishment of a dense vegetation cover that persists through the winter months. This is a well-known erosion <a href="https://doi.org/10.1111/j.1475-2743.2004.tb00379.x">control strategy</a>, protecting soil that is usually left bare and therefore <a href="https://iopscience.iop.org/article/10.1088/1748-9326/aba2fd">threatens the production of food</a> and pollutes water. </p>
<figure class="align-center ">
<img alt="In winter fields without crops are often exposed to erosion" src="https://images.theconversation.com/files/436741/original/file-20211209-15-va9mcl.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/436741/original/file-20211209-15-va9mcl.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/436741/original/file-20211209-15-va9mcl.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/436741/original/file-20211209-15-va9mcl.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/436741/original/file-20211209-15-va9mcl.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=565&fit=crop&dpr=1 754w, https://images.theconversation.com/files/436741/original/file-20211209-15-va9mcl.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=565&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/436741/original/file-20211209-15-va9mcl.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=565&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">In winter fields without crops are often exposed to erosion.</span>
<span class="attribution"><span class="source">Cristina McBride-Serrano</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Winter vegetation cover can also boost soil organic matter and can help stop excess nitrates from untimely or excessive fertiliser application leaching from the soil to pollute water supplies. And <a href="https://doi.org/10.1111/ele.12652">increased plant diversity</a> should improve soil health and indirectly suppress pests and disease, enhancing resilience to a changing climate.</p>
<p>Knowing what soils are on the farm, their condition and a plan to manage them is clearly important to ensure sustainable soil use. This will come as second nature to many farmers. Farmers will plan their cropping strategies for future seasons themselves, but how this will improve on what they will already be doing isn’t clear. It is still not known when the promised templates and guidance will be available and what it will look like.</p>
<p>The Sustainable Farming Incentive will provide three standard levels for soils management, each requiring more from farmers in return for higher payments. Currently only the introductory and intermediate levels have set what farmers will receive if they adopt these standards. The introductory arable and horticulture standard pays £22 per hectare and the intermediate standard £40 per hectare. </p>
<p>To qualify for payments for both levels, farmers will need to:</p>
<ul>
<li>undertake a soil assessment</li>
<li>produce a soil management plan</li>
<li>test soil organic matter</li>
<li>add organic matter, such as manure or cover crops, to a third of the land each year</li>
<li>have at least 70% of the land covered during winter months</li>
</ul>
<p>Doing this will improve soil structure, help control erosion, and improve the soil’s capacity to absorb water. Soil contains more carbon than all the animals and vegetation and within the atmosphere combined, so looking after it is essential to sequester carbon and improve resilience to climate change.</p>
<p>However, there are questions about the availability, quality and quantity of organic matter that farmers might use, and whether some organic materials, such as industrial by-products, may affect soil health. More detail is expected soon.</p>
<p>Incentivising wider soil testing of soil nutrients will provide farmers with better knowledge on <a href="https://onlinelibrary.wiley.com/doi/abs/10.1111/sum.12615">managing fertilisers</a> and manures, reducing nutrient losses to the environment that cause water pollution and <a href="https://theconversation.com/ocean-dead-zones-are-spreading-and-that-spells-disaster-for-fish-39668">damage to ecosystems</a>. </p>
<p>Establishing winter crops to cover the fields may be tricky in some parts of England, such as Cumbria, where the autumn climate does not always favour plant growth. Some plant breeders are producing varieties suited to improving soil health and producing a dense cover in cold and wet climatic conditions.</p>
<p>Clearly these environmental grants for farmers recognise the central role that soil plays in supporting crop production and helping meet the <a href="https://doi.org/10.5194/soil-2-111-2016">UN sustainable development goals</a>. As always the devil will be in the detail, but these new standards represent a major step in the right direction for the nation’s soils, and the environment.</p><img src="https://counter.theconversation.com/content/173190/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>John Quinton receives funding from NERC, BBSRC EPSRC and from Horizon 2020 of the European Community. He is a trustee of the Eden River's Trust. </span></em></p><p class="fine-print"><em><span>Cristina McBride-Serrano is a Lancaster University PhD student and receives funding from the James Hutton Institute and the Perry Foundation. Previously she has received funding from the European Commission for a Horizon 2020 project: Soil Hydrology research platform underpinning innovation to manage water scarcity in European and Chinese cropping systems (SHui). Project number: 773903.</span></em></p><p class="fine-print"><em><span>Ian Dodd receives funding from UKRI, the Global Challenges Research Fund and from Horizon 2020 of the European Community.</span></em></p>Soil health is at the heart of new government plans for farm payments with policies to increase soil organic matter and promote winter cover.John Quinton, Professor of Soil Science, Lancaster UniversityCristina McBride-Serrano, PhD Candidate in Soil Science, Lancaster UniversityIan Dodd, Professor of Sustainable Agriculture, Lancaster UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1731622021-12-05T07:18:57Z2021-12-05T07:18:57ZSoil isn’t dirt: it’s the foundation of life and needs real care<figure><img src="https://images.theconversation.com/files/435542/original/file-20211203-27-1fw2c5m.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">shutterstock</span> </figcaption></figure><p>Healthy soil is critical for life on earth. It can contribute to climate change mitigation and adaptation, food and nutrition security. It is central to achieving sustainable development goals. It is the foundation of life on land. It provides many ecosystem services and helps achieve ecosystem restoration. </p>
<p>The biggest challenge when it comes to soil is getting people to stop treating soil like dirt and start treating it with the respect it deserves. And this comes from soil stewardship, really caring for the land. But to do that, it’s important to understand the soil ecosystem that needs restoring. </p>
<p><a href="https://theconversation.com/lessons-from-kenya-on-how-to-restore-degraded-land-98178">Land degradation</a> is a serious problem when it comes to soil. Degraded landscapes are more vulnerable to the stresses of droughts, floods and erratic rainfall. Education about good soil practices is key, and people like farmers who use the soil need the tools to practise good soil management. </p>
<p>In today’s episode of Pasha, Leigh Ann Winowiecki, a soil systems scientist at the World Agroforestry, and Rattan Lal, a distinguished professor of soil science at Ohio State University, discuss why soil needs to be front and centre of global policies.</p>
<p>We’ve also collected some more articles about soil <a href="https://theconversation.com/africa/search?q=%23WorldSoilDay2021&sort=recency&language=en&date=all&date_from=&date_to=">here</a>.</p>
<hr>
<p><strong>Photo:</strong>
“Arid landscape in north Senegal. Eroded soil with few acacia trees. Traces of erosion on the sandy ground. Dry climate conducting to the desertification. Natural picture taken during the dry season.” By Boulenger Xavier <a href="https://www.shutterstock.com/image-photo/arid-landscape-north-senegal-eroded-soil-1020803248">Shutterstock</a></p>
<p><strong>Music</strong>
“Happy African Village” by John Bartmann, found on <a href="http://freemusicarchive.org/music/John_Bartmann/Public_Domain_Soundtrack_Music_Album_One/happy-african-village">FreeMusicArchive.org</a> licensed under <a href="https://creativecommons.org/publicdomain/zero/1.0/">CC0 1</a>.</p>
<p>“minimal ambient music/atmosphere fragment” by Clacksberg found on <a href="https://freesound.org/people/Clacksberg/sounds/495747/">Freesound</a> licensed under <a href="http://creativecommons.org/publicdomain/zero/1.0/">Creative Commons</a></p><img src="https://counter.theconversation.com/content/173162/count.gif" alt="The Conversation" width="1" height="1" />
The global community must understand the importance of soil in order to protect it.Ozayr Patel, Digital EditorLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1671622021-09-03T12:17:49Z2021-09-03T12:17:49ZHow special soil observatories in China are helping to create more sustainable agriculture<figure><img src="https://images.theconversation.com/files/419105/original/file-20210902-25-9ebigl.jpg?ixlib=rb-1.1.0&rect=10%2C5%2C3440%2C2276&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A typical limestone karst landscape in China.</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/green-paddy-oddly-shaped-karst-mountains-107638679">Tony V3112/Shutterstock</a></span></figcaption></figure><p>All over the world, agriculture is threatened by <a href="https://www.nhm.ac.uk/discover/soil-degradation.html">degraded soils</a>. Stripped of carbon from intensive farming, soils erode more easily, host fewer microbes and hold less water and nutrients. Fertilisers and pesticides applied to improve crop yields can leach beneath the soil and pollute the surrounding environment.</p>
<p>Soil degradation is a particularly big problem in China, where enormous pressure on natural resources from industrial-scale farming is accelerating the rate of soil erosion.</p>
<p>Looking for ways to make agriculture more sustainable can be difficult because the subject is so vastly complex, and crop and livestock productivity is often at odds with environmental sustainability. The effects of farming may stretch far beyond the topsoil studied by agricultural scientists. Adopting good sustainability practices requires farmers to buy into the idea, so an appreciation of their expertise and views is important. </p>
<p>Often experts from other countries are working in isolation from local scientific teams, risking poor decisions about agricultural practices that don’t acknowledge local conditions and cultures. This means decisions informed by science may not be the best decisions for farmers’ livelihoods or the environment. To avoid this problem, there needs to be more collaboration between scientists and local farmers. </p>
<p>A group of earth, environmental, agricultural and social scientists, we have been addressing these challenges in a <a href="http://www.czo.ac.cn">joint project</a> between the UK and China. This collaboration, arguably, set up the deepest ever exploration of how farming affects the environment. To do this we studied from the bottom of groundwater to the top of crop vegetation at five locations in China with vastly different geology.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/DcAmNUtZC04?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
</figure>
<h2>Critical zone observatories</h2>
<p>Sinking deep boreholes – down to 200m in places – enabled us to catalogue how much carbon was stored, the diversity of soil biology and the flow of pesticides, herbicides and fertilisers that leach into the environment. We assessed soil losses through erosion at the surface against rates of <a href="https://www.britannica.com/science/soil/Soil-formation">soil formation</a>, which is created from the breakdown of minerals from the geology below. We also explored many other processes, providing a comprehensive understanding of how landscapes work and how they are affected by farming. </p>
<figure class="align-right ">
<img alt="A diagram showing the critical zone of agricultural land from the groundwater to the top of the crop vegetation." src="https://images.theconversation.com/files/419063/original/file-20210902-15-2se1wa.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/419063/original/file-20210902-15-2se1wa.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=530&fit=crop&dpr=1 600w, https://images.theconversation.com/files/419063/original/file-20210902-15-2se1wa.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=530&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/419063/original/file-20210902-15-2se1wa.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=530&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/419063/original/file-20210902-15-2se1wa.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=666&fit=crop&dpr=1 754w, https://images.theconversation.com/files/419063/original/file-20210902-15-2se1wa.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=666&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/419063/original/file-20210902-15-2se1wa.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=666&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption"></span>
<span class="attribution"><span class="source">Mair Perkins</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Our team monitored soils at sites called <a href="https://czo-archive.criticalzone.org/national/research/the-critical-zone-1national/">critical-zone observatories</a>, which complement an international network set up originally to explore how landscapes evolve with <a href="https://www.nationalgeographic.org/encyclopedia/ecology/#:%7E:text=Ecology%20is%20the%20study%20of%20organisms%20and%20how%20they%20interact,living%20things%20and%20their%20habitats.&text=In%20addition%20to%20examining%20how,ecosystems%20do%20not%20function%20normally.">ecology</a> (the study of living organisms and their relationship with their physical environment).</p>
<p>Using this deep-monitoring approach, and a vast team of experts, we made new discoveries that would have been impossible if we had been working in isolation. There were some worrying findings. Across all sites, huge reserves of fertiliser were found deep below the topsoil.</p>
<p>For example, in the <a href="https://en.wikipedia.org/wiki/Loess_Plateau">Loess plateau</a>, the most erosion-prone landscape on Earth, over <a href="https://www.sciencedirect.com/science/article/pii/S0048969718310088">200 million tonnes of nitrogen</a> was found 50-100m under the ground. This equates to the amount of nitrogen that is applied as fertiliser each year around the world.</p>
<p>China’s <a href="https://whc.unesco.org/en/list/1248/">karst</a> landscapes, formed from limestone, have <a href="https://onlinelibrary.wiley.com/doi/10.1002/ece3.3502">one million tonnes</a> of nitrogen fertiliser flowing through their porous, cavernous geology each year. In highly weathered tropical soil environments, our previous research showed that more than <a href="https://www.sciencedirect.com/science/article/pii/S0016706118312771">80% of nitrogen leaches</a> below surface depths typically monitored by agricultural researchers. Rather than feed crops, this nitrogen poisons groundwater and feeds aquatic plants that strip rivers and lakes of oxygen when they decompose.</p>
<p>To find the source of this nitrogen and other environmental threats, we asked farmers, advisers and policymakers about <a href="https://www.sciencedirect.com/science/article/pii/S0167880919303317?via%3Dihub">their land-management choices</a>. Higher crop yields and a perception that “more is better” dominated their decisions. While policymakers were focused on preserving the environment and feeding the population, farmers seeking to maximise their income were wasting money on fertiliser leaching away.</p>
<figure class="align-center ">
<img alt="A graphic showing the location of the project's critical zone locations where they studied the area between groundwater and vegetation top." src="https://images.theconversation.com/files/419064/original/file-20210902-25-mv2iza.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/419064/original/file-20210902-25-mv2iza.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=451&fit=crop&dpr=1 600w, https://images.theconversation.com/files/419064/original/file-20210902-25-mv2iza.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=451&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/419064/original/file-20210902-25-mv2iza.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=451&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/419064/original/file-20210902-25-mv2iza.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=567&fit=crop&dpr=1 754w, https://images.theconversation.com/files/419064/original/file-20210902-25-mv2iza.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=567&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/419064/original/file-20210902-25-mv2iza.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=567&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Location of the critical zone observatories.</span>
<span class="attribution"><span class="source">Mair Perkins</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<h2>Passing on the knowledge</h2>
<p>Our next step has been to take this new knowledge and make it accessible to policymakers and, eventually, farmers. Our goal is to advise on land-management options that benefit crop yield, the environment and economics all at the same time. Cutting fertiliser use is an easy win. This can lower costs to the farmer without affecting yield and results in less fertiliser leaching into the surrounding environment. Decisions that lead to less chemical use save farmers money, but they need to be assured of producing the same yield.</p>
<p>There are also environmental costs that need to be factored in, so we brought in economists who are putting a monetary value on pollution and agricultural land degradation to help policymakers, government and farmers better understand the long-term costs of environmental deterioration. We are working to align the information we produce to the information they need to better protect the environment and improve their livelihoods, and help achieve UN <a href="https://sdgs.un.org/goals">sustainable development goals</a>.</p>
<p>Complex information is being simplified for use in computer programs and apps called <a href="https://ec.europa.eu/eip/agriculture/en/digitising-agriculture/developing-digital-technologies/decision-support-tools">decision-support tools</a>. We found over 400 of these tools were already in use in China, with most focusing on crop yield and a few exploring environmental effects, but none exploring both the environment and agriculture at the same time.</p>
<p>The computer models that make predictions for these tools are only as good as the available data and understanding. From the data we collected, we can improve these tools and check their output before using them over larger land areas. A huge market exists for decision-support tools to help with farming worldwide. By adding in the more comprehensive understanding from our critical-zone observatories in China, new tools will be more reliable and complete.</p>
<p>We cannot do this without the international partnerships that keep the thinking and debate fresh. Fragmented scientific evidence has been brought together by understanding how farming affects everything, from the crop vegetation to the geology deep below ground, alongside social perspectives from local farmers and government.</p>
<p>Addressing these agricultural and environmental challenges together offers more sustainable, environmentally friendly practices that maintain food production with greater profit to farmers. What we learned in China is helping to establish more critical-zone observatories in the UK and abroad, including those that focus on the effect of humans on the environment.</p><img src="https://counter.theconversation.com/content/167162/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Paul Hallett receives funding from UK Research and Innovation. </span></em></p><p class="fine-print"><em><span>Ganlin Zhang receives funding from the National Science Foundation of China; the Chinese Academy of Sciences; the European Commission; and the Ministry of Science and Technology of China. </span></em></p><p class="fine-print"><em><span>Larissa A. Naylor receives funding from UK Research and Innovation.</span></em></p><p class="fine-print"><em><span>Weikai Wang does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Soil degradation is a huge challenge for farmers around the world. But new research is showing how farmers can balance crop yields with protecting the environment.Paul Hallett, Professor in Soil Physics, University of AberdeenGanlin Zhang, Professor of Soil Science, Institute of Soil Science, Chinese Academy of SciencesLarissa A. Naylor, Professor of Geomorphology and Environmental Geography, University of GlasgowWeikai Wang, Research Associate, School of Geographical & Earth Sciences, University of GlasgowLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1569102021-05-19T16:02:07Z2021-05-19T16:02:07ZGreening the planet: we can’t just plant trees, we have to restore forests<figure><img src="https://images.theconversation.com/files/401614/original/file-20210519-19-19t24iq.jpg?ixlib=rb-1.1.0&rect=24%2C8%2C5439%2C3039&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/tropical-rainforest-stunning-view-borneo-sunrise-1474114256">Borneo Rimbawan/Shutterstock</a></span></figcaption></figure><p>The <a href="https://www.bbc.co.uk/news/uk-57137057">Queen’s Green Canopy</a>, a campaign to celebrate Elizabeth II’s platinum jubilee next year, involves asking people in the UK to plant trees: a “treebilee” as her son, Prince Charles puts it. This is one of a number of public and private campaigns underway, including initiatives by big corporations from <a href="https://www.nestle.com/stories/reforestation-project-one-tree-planted-biodiversity-climate-change">Nestle</a> to <a href="https://www.audi-umweltstiftung.de/umweltstiftung/en/projects/responsibility/planting-trees-against-climate-change.html">Audi</a> which are also planting millions of trees in an attempt to mitigate a portion of their environmental impact.</p>
<p>But, at a much smaller scale, there are thousands of community reforestation projects around the word whose goals differ depending on the environment and desires of local people. For example, planting native trees along the Kinabatangan river in Borneo can support local ecotourism businesses, while forest projects on the east coast of New Zealand are designed to protect agricultural soils from erosion. </p>
<p>Local context makes each community project unique and of more value, as people are more likely to plant the right trees in the right places for the right purpose. But these projects cost money and securing financing can be challenging when funders are so often focused on measurable goals and on removing carbon from the atmosphere to offset emissions-generating activities. Inevitably, small local projects bear the brunt, incurring the <a href="https://www.scientificamerican.com/article/the-real-cost-of-planting-trees/">steep cost</a> of monitoring and certification.</p>
<p>In 2019, we developed <a href="http://www.regrowborneo.org">Regrow Borneo</a>, a community-based reforestation project in Sabah, Malaysian Borneo, that thrust us into this complicated world. Our work prompted us to examine these trade-offs from the perspective of the cost of trees, the importance of traditional knowledge and the price of reforestation. </p>
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<h2>Cost of trees v value of forests</h2>
<p>The number of trees planted is often seen as an indicator of the success of reforestation projects. We’ve all seen adverts suggesting that if we buy a product a company will plant a tree to offset the cost of producing the item. Trees are relatively easy to count and, if planted in the right place, may reflect successful restoration. But reforestation occurs over hundreds of years and poorly managed projects that plant millions of trees can sometimes end with the <a href="https://www.theguardian.com/world/2020/jan/30/most-of-11m-trees-planted-in-turkish-project-may-be-dead">majority dying</a>. </p>
<p>That is why successful forest restoration projects take a <a href="https://onlinelibrary.wiley.com/doi/epdf/10.1111/rec.13035">long-term approach</a>, through comparing progress to existing forests, taking “before and after” snapshots, and measuring the social cost and benefits. But none of this can be captured by counting trees. A tree census will not tell you about the health of the ecosystem, soil, insect, bird or mammal populations. Neither will it tell you about a loss or gain of economic opportunities for local communities, their health, or spiritual wellbeing. We need new measures for evaluating projects, but none of these approaches is as simple, or easily explained to funders as a tree census.</p>
<p>Regrow Borneo plans to measure success in terms of restored forest area – a simple metric for reporting to donors that can be independently verified by drone footage or through advanced satellite and airborne technologies that can measure how the restored <a href="https://www.sciencedirect.com/science/article/abs/pii/S0169534714002249">ecosystem functions</a>. </p>
<h2>Synergy between science and local knowledge</h2>
<p>Effective forest restoration relies on a combination of scientific understanding, knowledge and experience. In the case of Regrow Borneo, the rich local knowledge allows us to predict how fast particular species grow, which species provide food for animals (such as orang-utans) and which are flood tolerant.</p>
<p>The <a href="https://www.tandfonline.com/doi/pdf/10.2980/19-3-3530?needAccess=true">most effective local projects</a> rely on this knowledge throughout their lifespan. But incorporating knowledge into measures of success for projects is difficult because often it simply can’t be measured. Demanding scientific rigour in local projects can lead communities to abandon this knowledge, which can <a href="https://iopscience.iop.org/article/10.1088/1748-9326/abd7ac/pdf">reduce the effectiveness</a> of the projects. The problem is that science needs to catch up and design better ways of incorporating this knowledge into its experiments. </p>
<figure class="align-center ">
<img alt="A baby orangutan peeping out from behind a tree in a rainforest in Borneo." src="https://images.theconversation.com/files/401615/original/file-20210519-17-47qhsn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/401615/original/file-20210519-17-47qhsn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/401615/original/file-20210519-17-47qhsn.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/401615/original/file-20210519-17-47qhsn.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/401615/original/file-20210519-17-47qhsn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/401615/original/file-20210519-17-47qhsn.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/401615/original/file-20210519-17-47qhsn.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Reforestation helps protect endangered species such as the orangutan.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/orangutans-babies-freedom-tanjung-puting-national-1395399326">Ignacio Salaverria/Shutterstock</a></span>
</figcaption>
</figure>
<h2>Who pays?</h2>
<p>The goals of community reforestation projects and those of funders don’t always align, which can place a huge burden on the community involved. Funders are sometimes focused on paying a fixed price that might cover planting a tree – but it cannot cover ensuring that a healthy tree flourishes. Other funders concerned about their reputation seek guarantees from projects through checks, certification and monitoring, which – though commendable – may not capture the whole picture of “success”. </p>
<p>For example, companies which burn carbon are allowed to offset this by paying forest projects for the amount of carbon they store. In return, companies want guarantees, so will seek projects that are independently certified. The rules of certification are designed to protect forests, but can also limit local access to forest resources and benefits. And the cost of certification and staff training falls on the projects themselves. </p>
<p>Models in which funders coordinate and pay for monitoring may help overcome some of the financial barriers for small projects. Within Regrow Borneo it has so far been difficult to develop a viable price for reforesting a healthy hectare as our commitment to fair wages, monitoring growth and replacing trees lost to flooding or eaten by monkeys can seriously raise costs. </p>
<p>Riskier reforestation sites such as <a href="https://www.theguardian.com/environment/2020/sep/24/what-is-carbon-capture-usage-and-storage-and-can-it-trap-emissions">carbon-rich peat swamps</a> and nature reserves involve frequent monitoring for biodiversity, adding further costs and pushing prices well above the rate that carbon is traded. Every community has different wage expectations, every forest requires different resources to restore, so a single price per tree or per tonne of carbon is an unreasonable expectation.</p>
<p>As a restoration community, we believe in a change of thinking. We need to bridge the gap between funders and projects by reducing the barriers to financing small projects. Flexible funding models and less rigid certification processes support the development of community-based forestry initiatives in a more pragmatic way. Projects such as <a href="https://trilliontrees.org">Trillion Trees</a> or <a href="https://restor.eco">Restor</a> that seek to network and fund community-based projects across the globe are excellent examples of good working models. Instead of funding a million trees, we should think of funding a million forests.</p><img src="https://counter.theconversation.com/content/156910/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Tristram Hales is a trustee and founding member of Regrow Borneo. </span></em></p><p class="fine-print"><em><span>Benoit Goossensi s a trustee and founding member of Regrow Borneo. </span></em></p><p class="fine-print"><em><span>Mike Bruford is a trustee and founding member of Regrow Borneo. </span></em></p>Planting trees can sometimes be a carbon-offset box-ticking exercise, but reforestation is a long-term commitment that supports communities, promotes biodiversity and tackles the climate emergency.Tristram Hales, Director, Sustainable Places Research Institute, Cardiff UniversityBenoit Goossens, Professor of Biology, Cardiff UniversityMike Bruford, Professor of Organisms and Environment, Cardiff UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1607042021-05-12T08:20:44Z2021-05-12T08:20:44ZPay dirt: $200 million plan for Australia’s degraded soil is a crucial turning point<figure><img src="https://images.theconversation.com/files/400212/original/file-20210512-18-61b5qy.jpg?ixlib=rb-1.1.0&rect=28%2C0%2C4665%2C3103&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Shutterstock</span></span></figcaption></figure><p>The food we eat, the clothes we wear, the air we breathe, the water we drink – it’s all underpinned by healthy and productive soils. Since Europeans arrived in Australia, the continent’s soil has steadily been degraded. Yet, until now, we’ve lacked an integrated national approach to managing this valuable and finite resource.</p>
<p>That changed in last night’s federal budget, when Treasurer Josh Frydenberg announced almost A$200 million for a <a href="https://www.awe.gov.au/sites/default/files/2021-05/national-soil-strategy-factsheet.pdf">National Soils Strategy</a>. The 20-year plan recognises the vital role of soils for environmental and human health, the economy, food security, biodiversity and climate resilience.</p>
<p>Our soils face a range of threats, including the loss of prime agricultural land, erosion, acidification, salt accumulation, contamination and carbon loss. Climate change also puts pressure on our soils through through droughts, storms, bushfires and floods.</p>
<p>We contributed expertise as the soil policy was being developed, and believe the final strategy represents a long-needed turning point for this crucial natural asset.</p>
<figure class="align-center ">
<img alt="farm in dust storm" src="https://images.theconversation.com/files/400214/original/file-20210512-17-1vmsho7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/400214/original/file-20210512-17-1vmsho7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=370&fit=crop&dpr=1 600w, https://images.theconversation.com/files/400214/original/file-20210512-17-1vmsho7.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=370&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/400214/original/file-20210512-17-1vmsho7.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=370&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/400214/original/file-20210512-17-1vmsho7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=465&fit=crop&dpr=1 754w, https://images.theconversation.com/files/400214/original/file-20210512-17-1vmsho7.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=465&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/400214/original/file-20210512-17-1vmsho7.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=465&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Australia’s soils have been degrading since European settlement.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<h2>Why soil matters</h2>
<p>Soil contains organic matter, minerals, gases, water and living organisms. It is slow to form – the average rate of soil production globally is <a href="https://www.sciencedirect.com/science/article/pii/S0016706113003601">around 114 millimetres per 1,000 years</a> – and is considered a non-renewable resource.</p>
<p>Soil underpins a myriad of economic activities. In Australia, it <a href="https://www.soilscienceaustralia.org.au/about/save-our-soils/sos-value-of-australias-soils/2">directly contributes about</a> A$63 billion each year to the economy through agriculture production alone.</p>
<p>Healthy soil is necessary for:</p>
<ul>
<li><p>food and fibre production </p></li>
<li><p>filtering water and retaining sediment to ensure healthy landscapes</p></li>
<li><p>maintaining air quality by preventing dust storms</p></li>
<li><p>carbon storage to help mitigate climate change</p></li>
<li><p>environmental functions such as plant growth </p></li>
<li><p>human nutrition (soil provides nutrients to plants and animals which are transferred to humans once consumed)</p></li>
<li><p>many drugs and vaccines upon which humans rely, such as penicillin</p></li>
<li><p>safe infrastructure (acid sulfate soils and salinity can damage structures such as housing, bridges and roads)</p></li>
<li><p>resilience to natural disasters such as storms, bushfires, floods and droughts. </p></li>
</ul>
<p>However, land degradation, climate change and poor management practices threaten our soil resources.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/even-after-the-rains-australias-environment-scores-a-3-out-of-10-these-regions-are-struggling-the-most-157590">Even after the rains, Australia's environment scores a 3 out of 10. These regions are struggling the most</a>
</strong>
</em>
</p>
<hr>
<figure class="align-center ">
<img alt="An overly saline mustard field" src="https://images.theconversation.com/files/400217/original/file-20210512-19-1mtlki0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/400217/original/file-20210512-19-1mtlki0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/400217/original/file-20210512-19-1mtlki0.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/400217/original/file-20210512-19-1mtlki0.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/400217/original/file-20210512-19-1mtlki0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/400217/original/file-20210512-19-1mtlki0.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/400217/original/file-20210512-19-1mtlki0.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Soil salinity can ruin crops.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<h2>What lies beneath?</h2>
<p>Until now, Australia has lacked a nationally consistent approach to monitor soil health, nor a readily accessible means of storing that data. That means at a national level, our understanding of soil condition, and how it’s changed, has been limited.</p>
<p>Soil monitoring has largely been conducted through various regional, state and federal programs. These often operate in isolation and have differing aims and objectives. And overall investment has not been large or quick enough to create broad improvements in soil health.</p>
<p>In comparison, well-established standardised national systems exist to monitor <a href="https://www.tern.org.au/">terrestrial ecosystems</a>, <a href="http://www.bom.gov.au/?ref=logo">weather, climate and water</a>. These allow an assessment of longer trends and changes to baseline conditions.</p>
<p>The need for a national soil assessment was recognised as far back <a href="https://theconversation.com/search/result?sg=3cba8a33-10bb-4731-b739-16817b5937c1&sp=1&sr=4&url=%2Fa-more-sustainable-australia-we-need-to-talk-about-our-soils-16555">as 2008</a>. And there have long been <a href="https://publications.csiro.au/rpr/download?pid=procite:6de96f40-58f0-4ddf-88de-fe874629fa1d&dsid=DS1">calls for</a> long-term monitoring, consistent information and baseline data collection. </p>
<figure class="align-center ">
<img alt="hand holding dirt" src="https://images.theconversation.com/files/400218/original/file-20210512-16-1871aho.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/400218/original/file-20210512-16-1871aho.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/400218/original/file-20210512-16-1871aho.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/400218/original/file-20210512-16-1871aho.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/400218/original/file-20210512-16-1871aho.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/400218/original/file-20210512-16-1871aho.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/400218/original/file-20210512-16-1871aho.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">The funding will help farmers monitor the health of their soil.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<h2>Change from the ground up</h2>
<p>Importantly, the strategy takes a long term view of sustainable soil management. It also considers soil beyond its traditional role in agricultural production and explicitly identifies criteria to measure progress.</p>
<p>The strategy has three arms:</p>
<p><strong>1. Prioritise soil health</strong></p>
<p>This goal takes a “soils first” approach in that sustainable soil management is the primary consideration in policy development and management strategies. This recognises how environmental and agricultural problems can start with poor soil management and create further challenges. For example, soil acidification can lead to <a href="https://publications.csiro.au/rpr/download?pid=csiro:EP177962&dsid=DS3">declines in terrestrial biodiversity</a>, and soil constraints must be addressed first to arrest this. </p>
<p><strong>2. Empower soil stewards and innovation</strong></p>
<p>This approach gives incentives to farmers and other land managers, such as rebates for sampling to determine the soil carbon levels. Carbon is an important measure of soil condition. Gathering such information will help land managers arrest the decline in soil condition, enhancing productivity and soil health.</p>
<p><strong>3. Secure soil science</strong></p>
<p>This approach aims to increase soil knowledge through standardised data collection, management and storage. It will allow for more informed decisions using reliable, up-to-date, accessible information. </p>
<p>Part of this aim involves strengthening training and accreditation programs, and integrating soils into the national school curriculum. This will help create a new generation of soil experts to replace the current crop which is trending to retirement.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/we-need-more-carbon-in-our-soil-to-help-australian-farmers-through-the-drought-102991">We need more carbon in our soil to help Australian farmers through the drought</a>
</strong>
</em>
</p>
<hr>
<figure class="align-center ">
<img alt="young woman conducting soil testing" src="https://images.theconversation.com/files/400219/original/file-20210512-15-152kp70.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/400219/original/file-20210512-15-152kp70.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/400219/original/file-20210512-15-152kp70.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/400219/original/file-20210512-15-152kp70.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/400219/original/file-20210512-15-152kp70.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/400219/original/file-20210512-15-152kp70.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/400219/original/file-20210512-15-152kp70.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">The strategy aims to train a new generation of soil experts.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<h2>On solid ground</h2>
<p>Overall, the National Soils Strategy aims to deliver coordinated on-ground action and improve research, education and monitoring. The strategy broadly aligns with the needs of those who had input into its development, including governments, industry, academia, Landcare groups and non-government organisations. </p>
<p>However, while the importance of Indigenous land management practices is clearly acknowledged, the integration and incorporation of these practices should be more clearly defined. </p>
<p>The monitoring program encourages farmers to test their soil and incorporate the de-identified results in to the national database. Care should be taken to ensure <a href="https://ebooks.publish.csiro.au/content/soil-analysis-interpretation-manual">sampling is done appropriately</a> for the data to be useful. </p>
<p>The time frame for the initial phase of the strategy is short – pilot programs need to be delivered between two and four years. This will be challenging to deliver.</p>
<p>Separate to the strategy, the budget allocated A$59.6 million to soil carbon initiatives. There is <a href="https://www.pmc.gov.au/news-centre/domestic-policy/digging-deep-soil-organic-carbon-earth-day">increasing recognition</a> of how improved land use and management can help boost soil carbon stores, which is key to tackling climate change. But storing carbon permanently in soils comes with a number of <a href="https://theconversation.com/dishing-the-dirt-australias-move-to-store-carbon-in-soil-is-a-problem-for-tackling-climate-change-141656">challenges</a>. This funding may be appropriate only if directed to address those areas where knowledge gaps exist. </p>
<p>But overall, the strategy fills a vital gap – providing a national vision and shared goals for managing precious soils across Australia.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/the-morrison-government-wants-to-suck-co-out-of-the-atmosphere-here-are-7-ways-to-do-it-144941">The Morrison government wants to suck CO₂ out of the atmosphere. Here are 7 ways to do it</a>
</strong>
</em>
</p>
<hr>
<img src="https://counter.theconversation.com/content/160704/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Vanessa Wong receives funding from the Victorian State Government and the Australian Research Council. She is currently the President of Soil Science Australia, a not-for-profit, professional association for soil scientists and people interested in the responsible management of Australia’s soil resources.</span></em></p><p class="fine-print"><em><span>Luke Mosley receives funding from the South Australian and Commonwealth Governments for various projects. He is Immediate Past President and is affiliated with Soil Science Australia, a not-for-profit, professional association for soil scientists and people interested in the responsible management of Australia’s soil resources.</span></em></p>Soil underpins Australia’s economy – yet since Europeans arrived, the natural asset has steadily been degraded. A new national plan aims to change that.Vanessa Wong, Associate professor, Monash UniversityLuke Mosley, Associate Professor, University of AdelaideLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1464492020-10-04T07:26:21Z2020-10-04T07:26:21ZKey insights into land degradation from seven African countries<figure><img src="https://images.theconversation.com/files/360815/original/file-20200930-20-16q0ncl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A maize farmer in Kenya surveys his degraded land.</span> <span class="attribution"><span class="source">Photo by David Bathgate/Corbis via Getty Images</span></span></figcaption></figure><p>Land is essential to our lives – we grow food on it and rely on it for economic growth and development. In sub-Saharan Africa approximately <a href="https://www.un.org/esa/sustdev/csd/csd16/rim/eca_bg3.pdf">83%</a> of people depend directly on land for survival. </p>
<p>However, <a href="http://2sc.unccd.grforum.org/fileadmin/unccd/upload/documents/Background_documents/Background_Document_web3.pdf">approximately</a> two-thirds of the continent’s productive land is <a href="https://www.unccd.int/sites/default/files/relevant-links/2017-08/v2_201309-unccd-bro_web_final.pdf">degraded</a> – it <a href="https://www.unccd.int/sites/default/files/relevant-links/2017-08/v2_201309-unccd-bro_web_final.pdf">has lost</a> its productive capacity – to some degree. This is driven by years of overgrazing, inappropriate agricultural practices, extreme weather events and the conversion of forest land into farm land. The future doesn’t look promising either as Africa <a href="http://www.fao.org/3/CA8753EN/CA8753EN.pdf">is the only</a> continent where deforestation and forest conversion to agricultural land is on the rise. </p>
<p>Reversing and preventing land degradation is critical if we want ecosystems to keep working; for instance, providing food, fresh water and regulating the climate, natural disasters, and pests. </p>
<p>Fortunately, there is considerable global commitment to reverse and halt further land degradation. The <a href="https://www.bonnchallenge.org/">Bonn Challenge</a>, for instance, is a global effort to restore 350 million hectares of degraded land by 2030. There are also several important regional initiatives, such as the <a href="https://afr100.org/">Africa Forest Landscape Restoration Initiative</a> (AFR100), which aims to restore 100 million hectares by 2030.</p>
<p>Regreening Africa is another effort that my colleagues and I have been working on. Funded by the European Union and led by World Agroforestry together <a href="https://www.worldvision.com.au/">with</a> <a href="https://www.crs.org/">five</a>
<a href="https://www.oxfam.org/en">non-govermental</a> <a href="https://www.care-international.org/">organisations</a> <a href="https://ccafs.cgiar.org/partners/sahel-eco">(NGOs)</a>, the programme works directly with 500,000 households to restore one million hectares of agricultural land. The programme is happening in Ethiopia, Ghana, Kenya, Mali, Niger, Rwanda, Senegal and Somalia. </p>
<p>In 2018, we carried out a <a href="http://www.worldagroforestry.org/publication/regreening-africa-consolidated-baseline-survey-report">baseline survey</a> in seven of the eight participating countries, which has just been <a href="http://apps.worldagroforestry.org/downloads/Publications/PDFS/RP20046.pdf">published</a>. </p>
<p>We found high levels of land degradation in programme sites across all seven countries. We also found that farm incomes were generally low, though trees were present on most farms and most farmers had already engaged in re-greening activities.</p>
<p>These findings will allow us to assess how the Regreening Africa programme will affect people and the environment and generate evidence on how land restoration efforts can be scaled up, a key aim of this initiative. </p>
<h2>Baseline levels of degradation</h2>
<p>Regreening Africa works by supporting farming households to plant appropriate tree species on their farms and facilitate their natural regeneration. Farmers are linked to tree product value chains as an incentive. </p>
<p>In addition, the project promotes other land restoration practices, such as intercropping, reduced tillage, soil erosion control structures and water harvesting.</p>
<p>Our data collection focused on levels of exposure to agroforestry training, the uptake of regreening practices, indicators of land degradation – such as soil erosion, soil organic carbon, and vegetative cover – and farm income. </p>
<p>Using satellite imagery and scientific models, we detected high levels of land degradation. Soil erosion prevalence – a key indicator of land degradation – was found to be high in all seven countries, but highest in Niger, where over 75% of the fields were found to be highly degraded. The highest variation of soil erosion was found in Kenya, where approximately half of fields were both above and below 50% erosion prevalence. </p>
<h2>Trees on farm</h2>
<p>Across the seven countries, 94% of households reported the presence of at least one tree on their farm or homestead. The estimated average number per hectare was 150. </p>
<p>This average value masks the huge variation in numbers and species composition. For instance, households in East Africa had an average of 195 trees per hectare on relatively small land holdings. By contrast, there was an average of 12 trees per hectare on the larger farms of the Sahelian action sites.</p>
<p>We are also tracking the ratio of native to exotic species to ensure the ecosystem balance isn’t being undermined. In general, households tended to have more native trees species on their farms compared with exotic species. This trend applied to all countries, save for Rwanda. </p>
<h2>Regreening action</h2>
<p>What was encouraging is that over half of survey households (59%) undertook action to scale up trees on their farms in the year prior to being interviewed. This action varied across and within the seven countries. </p>
<p>Action to address degradation was found to be highest among Kenyan households, followed by those of Ethiopia. The most popular action undertaken was pruning existing trees on farm (36% of households), followed by tree planting (20% of households). </p>
<p>The survey also captured data on exposure to regreening-related training in the 12 months before they were surveyed. This was found to be low at 15% overall (11% women and 18% men), but with statistically significant variation across countries. </p>
<h2>Farm income</h2>
<p>One of Regreening Africa’s central hypotheses is that farmers are more likely to invest in land restoration, including tree establishment, if they can clearly see the potential financial benefits from doing so. This is expected to be through, for instance, the future promise of selling tree-related products, such as fruits, timber and honey, or through boosting crop productivity, resulting from the restoration of degraded soils. </p>
<p>Consequently, the baseline survey captured data on baseline levels of both total farm income and income specific to tree products. Because trees take time to establish, such income streams were modelled over 10 year time horizons. </p>
<p>The without-project (“business as usual”) projections for total farm income (income from both crops and tree products) were found to be generally low but with considerable variation across countries and households. For example, average Year 1 per capita projections ranged from US$690 for Niger to US$3,150 for Mali. </p>
<p>The 10-year per capita projected returns for tree products was found to be highest for Rwanda at US$4,858 on average, followed by Kenya (US$1,625 on average) and Mali (US$1,448 on average). Indeed, Rwanda was the only country where tree products made up a significant share of projected farm returns, given high levels of historical investment in fruit tree production. There is therefore significant room to bolster the economic contribution of trees in the farming systems Regreening Africa is targeting.</p>
<h2>Implications</h2>
<p>An overarching conclusion following the baseline survey is that there is huge variation both across and within the seven countries. No one size fits all. Regreening Africa must therefore ensure that restoration practices are carefully tailored to the local context. It’s also important to meet the goals of restoration and income generation simultaneously. </p>
<p>Regreening Africa is now at about the halfway mark of activity implementation. Much progress has been made, with field teams adjusting their operations to the new COVID-19 reality. The programme’s final survey will (hopefully) take place in a post-pandemic world and with strong evidence that it is possible to produce the food people need without undermining the health of the land.</p><img src="https://counter.theconversation.com/content/146449/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Karl Hughes receives funding from multiple organizations that fund international agricultural research. </span></em></p>Regreening Africa works directly with 500,000 households to restore one million hectares of agricultural land.Karl Hughes, Head of Monitoring, Evaluation and impact Assessment, Center for International Forestry Research – World Agroforestry (CIFOR-ICRAF)Licensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1293532020-01-07T04:30:01Z2020-01-07T04:30:01ZBushfires threaten drinking water safety. The consequences could last for decades<figure><img src="https://images.theconversation.com/files/308718/original/file-20200107-123389-edvby6.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C2995%2C1998&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Warnings about poor drinking water quality are in place in some areas affected by the bushfires.</span> <span class="attribution"><span class="source">From shutterstock.com</span></span></figcaption></figure><p>Bushfires pose serious short- and long-term impacts to public drinking water quality. They can damage water supply infrastructure and water catchments, impeding the treatment processes that normally make our water safe to drink.</p>
<p>Several areas in New South Wales and Victoria have already been issued with <a href="https://www.begavalley.nsw.gov.au/cp_themes/default/page.asp?p=DOC-QCM-74-68-40">warnings</a> about the quality of their drinking water.</p>
<p>Here’s what we know about the short- and long-term risks.</p>
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Read more:
<a href="https://theconversation.com/how-to-monitor-the-bushfires-raging-across-australia-129298">How to monitor the bushfires raging across Australia</a>
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<h2>Short-term risks</h2>
<p>Bushfires can damage or disrupt water supply infrastructure as they burn. And the risks can persist after the fires are out.</p>
<p>A loss of power, for example, disables important water treatment processes such as chlorine disinfection, needed to kill microorganisms and make our water safe to drink.</p>
<p>Drinking water for the towns of <a href="https://www.begavalley.nsw.gov.au/cp_themes/default/page.asp?p=DOC-QCM-74-68-40">Eden and Boydtown</a> on the NSW south coast has been affected in this way over recent days. Residents have been advised to boil their water before drinking it and using it for cooking, teeth brushing, and so on.</p>
<p>Other towns including <a href="https://www.begavalley.nsw.gov.au/cp_themes/default/page.asp?p=DOC-ZDJ-77-62-43">Cobargo and Bermagui</a> received similar warnings on New Year’s Eve.</p>
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Read more:
<a href="https://theconversation.com/disaster-recovery-from-australias-fires-will-be-a-marathon-not-a-sprint-129325">Disaster recovery from Australia's fires will be a marathon, not a sprint</a>
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<p>In some cases, untreated water, straight from a river supply, may be fed directly into drinking water systems. Water treatment plants are bypassed completely, due to damage, power loss, or an inability to keep pace with high volumes of water required for firefighting.</p>
<p>We’ve seen this in a number of southern NSW towns this week including <a href="https://www.snowyvalleys.nsw.gov.au/Public-Notices/Batlow-Water-Supply-System-Boil-Water-Alert">Batlow</a>, <a href="https://www.snowyvalleys.nsw.gov.au/Public-Notices/Adelong-Boil-Water-Alert">Adelong</a>, <a href="https://www.snowyvalleys.nsw.gov.au/Public-Notices/Tumbarumba-Water-Boil-Alert">Tumbarumba</a>, and the southern region of <a href="https://www.naroomanewsonline.com.au/story/6563313/power-restored-to-most-homes-princes-hwy-open-info-for-eurobodalla-shire-residents/?cs=12">Eurobodalla Council</a>, stretching from Moruya to Tilba. Residents of these areas have also been urged to boil their drinking water.</p>
<p>Untreated river water, or river water which has not been properly disinfected with chlorine, is usually not safe for drinking in Australia. Various types of bacteria, as well as the parasites giardia and cryptosporidium, could be in such water. </p>
<p>Animals including cattle, birds and kangaroos can excrete these microorganisms into river water. Septic tanks and sewage treatment plants may also discharge effluents into waterways, adding harmful microorganisms. </p>
<p>Human infection with these microorganisms can cause a range of illnesses, including gastrointestinal diseases with symptoms of diarrhoea and vomiting.</p>
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Read more:
<a href="https://theconversation.com/what-are-parasites-and-how-do-they-make-us-sick-121489">What are parasites and how do they make us sick?</a>
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<h2>Long-term risks</h2>
<p>Bushfires can damage drinking water catchments, which can lead to longer term threats to drinking water. Drinking water catchments are typically forested areas, and so are vulnerable to bushfire damage. </p>
<p>Severe impacts to waterways may not occur until after intense rainfall. Heavy rain can wash ash and eroded soil from the fires into waterways, affecting drinking water supplies downstream.</p>
<p>For example, bushfire ash contains nutrients, such as nitrogen and phosphorous. Increased nutrient concentrations can stimulate the growth of cyanobacteria, commonly known as “blue-green algae”. </p>
<p>Cyanobacteria produce chemicals which may cause a range of water quality problems, including poor taste and odour. Some cyanobacteria can produce toxic chemicals, requiring very careful management to protect treated drinking water.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/308720/original/file-20200107-123403-cj96ai.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/308720/original/file-20200107-123403-cj96ai.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/308720/original/file-20200107-123403-cj96ai.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/308720/original/file-20200107-123403-cj96ai.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/308720/original/file-20200107-123403-cj96ai.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/308720/original/file-20200107-123403-cj96ai.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/308720/original/file-20200107-123403-cj96ai.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<span class="caption">Boiling water will kill microorganisms, but not chemical substances.</span>
<span class="attribution"><span class="source">From shutterstock.com</span></span>
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<p>Many water treatment plants include filtration processes to filter small suspended particles from the water. But an increase in suspended particles, like that which we see after bushfires, would challenge most filtration plants. The suspended particles would be removed, but they would clog the filters, requiring them to be more frequently pulled from normal operation and cleaned.</p>
<p>This cleaning, or backwashing, is a normal part of the treatment process. But if more time must be spent backwashing, that’s less time the filters are working to produce drinking water. And if the rate of drinking water filtration is slowed and fails to keep pace with demand, authorities may place limitations on water use.</p>
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<strong>
Read more:
<a href="https://theconversation.com/the-bushfires-are-horrendous-but-expect-cyclones-floods-and-heatwaves-too-129328">The bushfires are horrendous, but expect cyclones, floods and heatwaves too</a>
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<h2>Boiling water isn’t always enough</h2>
<p>In order to reduce the risk of gastrointestinal and other illnesses, water suppliers and health departments may issue a <a href="https://www.health.nsw.gov.au/environment/water/Pages/boil-water-alert-guidance.aspx">boil water alert</a>, as we’ve seen in the past week. Bringing water to a “rolling boil” can reliably kill most of the microorganisms of concern.</p>
<p>In cases where water may be contaminated with chemical substances rather than microorganisms, boiling is usually not effective. So where there’s a risk of chemical contamination, public health messages are usually “do not drink tap water”. This means bottled water only.</p>
<p>Such “do not drink” alerts were issued this week following bushfire impacts to water treatment plants supplying the Victorian towns of <a href="https://www.egwater.vic.gov.au/do-not-drink-tap-water-message-for-buchan/">Buchan</a> and <a href="https://www.egwater.vic.gov.au/omeo-do-not-drink-tap-water/">Omeo</a>.</p>
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<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/how-does-poor-air-quality-from-bushfire-smoke-affect-our-health-126835">How does poor air quality from bushfire smoke affect our health?</a>
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<p>Impacts to catchments from bushfires and subsequent erosion can have long-lasting effects, potentially worsening untreated drinking water quality for many years, even decades. </p>
<p>Following these bushfires, many water treatment plant operators and catchment managers will need to adapt to changed conditions and brace for more extreme weather events in the future.</p><img src="https://counter.theconversation.com/content/129353/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Stuart Khan receives funding from a variety of national and international research funding agencies including the Australian Research Council (ARC), Water Research Australia (WaterRA) and the US Water Research Foundation (WRF). He also receives funding from industry including many Australian drinking water utilities.</span></em></p>Damage to water supply infrastructure and catchments during and after bushfires inhibits the treatment processes that normally make our water safe to drink.Stuart Khan, Professor of Civil & Environmental Engineering, UNSW SydneyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1281662019-12-16T14:39:03Z2019-12-16T14:39:03ZSoil is our best ally in the fight against climate change – but we’re fast running out of it<figure><img src="https://images.theconversation.com/files/307141/original/file-20191216-124009-r15aq1.JPG?ixlib=rb-1.1.0&rect=0%2C0%2C4608%2C3456&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">What lies beneath? Not a lot.</span> <span class="attribution"><span class="source">Dan Evans</span>, <span class="license">Author provided</span></span></figcaption></figure><p>Take a handful of soil and hold it up to your nose. That fresh, earthy aroma is organic matter, part of which is carbon. What you can smell is the whiff of a solution for dealing with climate change. </p>
<p>Global soil resources contain <a href="https://blogs.ei.columbia.edu/2018/02/21/can-soil-help-combat-climate-change/">more organic carbon</a> than the world’s atmosphere and all of its plants combined. When plants photosynthesise, they take carbon out of the atmosphere and when they die, that carbon is returned to the soil. </p>
<p>Storing more carbon in the soil helps to remove carbon dioxide from the atmosphere. But it also helps release nutrients for plant growth and improves the structure of the soil, enhancing how well it retains water. </p>
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Read more:
<a href="https://theconversation.com/france-has-a-great-plan-for-its-soil-and-its-not-just-about-wine-47335">France has a great plan for its soil – and it's not just about wine</a>
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<p>Maintaining these soil ecosystem services will become more important over the next few decades. By 2050, the global population is <a href="https://www.un.org/development/desa/en/news/population/world-population-prospects-2017.html">estimated to soar to more than 9 billion</a>, and that will mean a much greater demand on the world’s soil. In business, when demand for a product grows, you increase its production. But for soil, it’s a different story. </p>
<p>Soil is largely made at the bedrock deep below the Earth’s surface, and it is a slow process. Across the world, soil erosion, which is accelerated by some agricultural activities, is exceeding the rates at which new soils can form. As a soil thins, its productivity wanes. Less soil means a lower capacity to store nutrients, water and carbon. The long-term ability for soils to slow climate change and feed the world is under threat.</p>
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<img alt="" src="https://images.theconversation.com/files/307144/original/file-20191216-124027-1qiguy0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/307144/original/file-20191216-124027-1qiguy0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=337&fit=crop&dpr=1 600w, https://images.theconversation.com/files/307144/original/file-20191216-124027-1qiguy0.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=337&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/307144/original/file-20191216-124027-1qiguy0.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=337&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/307144/original/file-20191216-124027-1qiguy0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=423&fit=crop&dpr=1 754w, https://images.theconversation.com/files/307144/original/file-20191216-124027-1qiguy0.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=423&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/307144/original/file-20191216-124027-1qiguy0.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=423&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Intensive agriculture erodes soil at a worrying rate.</span>
<span class="attribution"><a class="source" href="https://unsplash.com/photos/dBi88gu1WXI">Jaromír Kavan/Unsplash</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
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<h2>Tick tock from soil to rock</h2>
<p>How many years might the world’s soils have left to support crop production? To store and purify water? To sequester enough atmospheric carbon to halt the climate emergency? Until now, there have been few measurements of how fast soil is being formed and eroded on land currently supporting agriculture. Efforts to understand this have been similar to forecasting a bank balance using just the expenditures. </p>
<p><a href="https://www.soil-journal.net/5/253/2019/soil-5-253-2019.html">Our research</a> is the first in the world to make a clear scientific estimate of soil lifespans, using measured rates of soil formation and erosion, giving farmers and scientists a more accurate idea of how sustainable the world’s soil resources are.</p>
<p>Measuring soil formation at an arable farm in Nottinghamshire, UK, we estimated that the uppermost 30 centimetres could be eroded in as little as 138 years, with the underlying sandstone bedrock emerging in 212 years. This may not seem like an urgent crisis. But given that these soils have been functioning for the last 10,000 years, this projection could be the final 1% of their lifespan.</p>
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<p>In other regions of the world, soils that have been subject to centuries of intensive agriculture have already thinned significantly. In sub-Saharan Africa, Asia, and Latin America and the Caribbean, the threat of soil erosion is high and <a href="http://www.fao.org/documents/card/en/c/c6814873-efc3-41db-b7d3-2081a10ede50/">soil functioning is considered to be deteriorating</a>. </p>
<p>In these regions, where rates of soil erosion are often greater than those for the UK, soil lifespans may be much shorter. Since the demands on soil will only intensify as the global population grows, societies will need to adapt to reverse the trajectory of soil thinning and, instead, find ways of thickening soils and extending their lifespans.</p>
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Read more:
<a href="https://theconversation.com/our-new-research-is-tracing-the-development-of-the-worlds-vital-non-living-nature-125664">Our new research is tracing the development of the world's vital non-living nature</a>
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<h2>Saving earth on Earth</h2>
<p>Discuss soil conservation and you join a conversation sustained over thousands of years. Nearly every civilisation has, to varying degrees, contributed to the debate. As a result, we’re lucky today to have an extensive and well-tested toolkit at our disposal with which to save the world’s soils. </p>
<p>These include relatively minor changes in agricultural practices. For example, planting crops across, rather than down, a hillslope can interrupt the flow of water and stop it from picking up and removing soil. Planting trees and ensuring soils are always vegetated with a cover crop such as clover between cropping seasons can also slow water and trap soil.</p>
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<img alt="" src="https://images.theconversation.com/files/307143/original/file-20191216-123987-1o2giv0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/307143/original/file-20191216-123987-1o2giv0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/307143/original/file-20191216-123987-1o2giv0.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/307143/original/file-20191216-123987-1o2giv0.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/307143/original/file-20191216-123987-1o2giv0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=502&fit=crop&dpr=1 754w, https://images.theconversation.com/files/307143/original/file-20191216-123987-1o2giv0.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=502&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/307143/original/file-20191216-123987-1o2giv0.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=502&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<span class="caption">Converting arable land to grassland can help restore soil, allowing it to store more carbon.</span>
<span class="attribution"><a class="source" href="https://unsplash.com/photos/w_CS5YBwev8">Mimi Di Cianni/Unsplash</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
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<p>In May 2019, I attended the <a href="http://www.fao.org/about/meetings/soil-erosion-symposium/en/">Global Symposium on Soil Erosion</a> in Rome. A lot of water (and soil) has passed underneath the Pons Fabricius bridge since ancient Roman farmers stood and discussed soil conservation over their hedgerows. </p>
<p>The symposium brought not only farmers together, but scientists, government officials, and land managers too. Soil erosion is a global issue, so conversations between people with different backgrounds and skills are essential. But the message that emerged from the symposium was relatively simple. For a decent future for all, we must save the world’s soils. And the clock is ticking.</p><img src="https://counter.theconversation.com/content/128166/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Dan Evans is a member of the Soils Training and Research Studentships (STARS) Centre for Doctoral Training (CDT) and is affiliated with Lancaster University, British Geological Survey, and University of Edinburgh.
He has received funding from the STARS CDT, and from the NERC Cosmogenic Isotope Analysis Facility, East Kilbride, Scotland. </span></em></p>Areas of the UK may lose their topsoil in little over a century according to new research.Dan Evans, PhD Researcher in Soil Science, Lancaster UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1161762019-05-30T19:50:57Z2019-05-30T19:50:57ZTrees, the ancient Macedonians, and the world’s first environmental disaster<p>It’s a simple enough equation: good soil is the key to good food. And good soil starts with trees. </p>
<p>Alexander the Great conquered a vast empire that extended from Greece all the way to India. However, his ancestors’ fortune was a mixed bag. A new series of studies show the ancient Macedonians may have been struck by one of the earliest environmental disasters linked to human activity. </p>
<p>Ancient sediment records sealed in lakes for thousands of years reveals how logging may have affected erosion, which ultimately destroyed the capacity of the ancient Macedonians to grow food. </p>
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Read more:
<a href="https://theconversation.com/soil-is-the-key-to-our-planets-history-and-future-116330">Soil is the key to our planet's history (and future)</a>
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<p>More trees, on the other hand, appears to have made soil erosion less susceptible to climate change. The lessons for modern people – and our future prosperity – are clear.</p>
<h2>Soil is a kingmaker</h2>
<p>Something wonderful happens when rocks, formed in the guts of the Earth, come into contact with air and water: they break down into clays (and other things) to form soils. Because of their ability to store water and nutrients, soils are the food basket of land plants and all the animals that feed on them, including us.</p>
<p>Preserving soil has been the key for success to all past civilisations. Those who lost it would rapidly be precipitated into oblivion. This happened everywhere: <a href="https://www.pnas.org/content/104/33/13268">the Middle East, Greece, Rome and Mesamerica</a>. </p>
<p>Preserving our soil should therefore be at the centre of our concerns (although it rarely gets a look-in on the nightly news).</p>
<p>Erosion isn’t just a problem because the land loses soil. This soil enters waterways, increasing the sediment load of rivers. This high sediment load harms freshwater and coastal ecosystems, including fish population and, ultimately, us. We therefore need to better understand how climate change and humans shape soil erosion.</p>
<h2>Macedonian timber and the first environmental disaster</h2>
<p>The chemistry of sediments deposited on lake’s bottom records how the environment changed over hundreds and thousands of years. Recently, <a href="https://www.nature.com/articles/s41598-017-18603-4">we have studied sediments from Lake Dojran</a>, straddling the border between Northern Macedonia and Greece. We looked at the past 12,000 years of sediment archive and found about 3,500 years ago, a massive erosion event happened. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/500-years-of-drought-and-flood-trees-and-corals-reveal-australias-climate-history-51573">500 years of drought and flood: trees and corals reveal Australia's climate history</a>
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<p>Pollen trapped in the lake’s sediment suggests this is linked to deforestation and the introduction of agriculture in the region. Macedonian timber was highly praised for ship building at the time, which could explain the extent of deforestation.</p>
<p>A massive erosion event would have catastrophic consequences for agriculture and pasture. Interestingly, this event is followed by the onset of the so-called <a href="https://en.wikipedia.org/wiki/Greek_Dark_Ages">Greek “Dark Ages”</a> (3,100 to 2,850 years ago) and the demise of the highly sophisticated Bronze Age Mycenaean civilisation.</p>
<p>Further to the west, at the crossroads between Albania and Norther Macedonia, Lake Ohrid holds a much longer storyline: an <a href="https://www.icdp-online.org/projects/world/europe/lake-ohrid-macedonia/details/">international scientific drilling program</a> is uncovering the past million year of climate and environmental stories locked in Lake Ohrid sediments. </p>
<p>We <a href="https://www.sciencedirect.com/science/article/pii/S0921818118305502">recently looked at Lake Ohrid</a> on a more modest time scale, similar to the Lake Dojran project: the past 16,000 years.</p>
<p>At Lake Ohrid, there are also signs of increased soil erosion around 4,000 years ago. These results are consistent with <a href="https://journals.sagepub.com/doi/abs/10.1177/0959683607076449">previous suggestions of a human role on soil erosion at other lakes in Greece</a>. </p>
<p>Overall, there are clear signs that deforestation and the development of agriculture precedes the Greek “Dark Ages”. While the causal link cannot be established with certainty, this timeline could represent the first negative feedback loop where humans depleted environmental resources, which in turn harmed communities.</p>
<h2>Trees can make soil less sensitive to climate change</h2>
<p>Lake Ohrid tells us another interesting story: until 8,000 years ago, soil erosion was closely following climate change. During dry and cold periods, erosion was shallow, probably as a consequence of dry conditions; while during warmer periods, higher levels of erosion delivered more sediment to the lake. </p>
<p>Around 8,000 years ago, something interesting happens: trees become the dominant type of vegetation cover. While trees were already abundant in previous warm periods (and less during cold periods), from 8,000 years ago onwards, they overwhelm the type of pollen that fell into the lake and became trapped in the sediment. </p>
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<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/forest-soil-needs-decades-or-centuries-to-recover-from-fires-and-logging-110171">Forest soil needs decades or centuries to recover from fires and logging</a>
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</em>
</p>
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<p>This tree dominance has an important consequence for soil erosion: after 8,000 years ago, soil erosion became shallow and remained so, even while the climate continued to oscillate. We can see soil erosion became less sensitive to climatic fluctuations.</p>
<p>We already knew that trees, thanks to their deep roots, help stabilise soil and prevent its loss; what we learn here is that over a certain threshold of tree cover, they also make soil erosion much less sensitive to climate change.</p>
<p>Lake Ohrid provides us with an important lesson, especially as we are increasingly concerned with how our soil and water resources will be affected by global warming. If we want to preserve our soils and rivers (and feed our communities) we need to ensure that enough of our landscape is covered with trees. </p>
<p>Planting trees and forest management should not be a concern for nature enthusiasts only, but for all us – regardless of political inclination – who enjoy eating. Understanding the past is not simply about learning from our ancestors’ mistakes so we do not repeat them, but freeing ourselves from their grip so <a href="https://en.wikipedia.org/wiki/Homo_Deus:_A_Brief_History_of_Tomorrow">new paths unfold ahead of us</a>.</p><img src="https://counter.theconversation.com/content/116176/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Anthony Dosseto receives funding from the Australian Research Council</span></em></p><p class="fine-print"><em><span>Alex Francke receives funding from the German Research Foundation (DFG) grant FR3783/1-1</span></em></p>Thousands of years of history tells the same story over and over: you ignore soil at your peril.Anthony Dosseto, Associate Professor, University of WollongongAlexander Francke, Research Fellow, University of WollongongLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/436412015-07-13T20:18:09Z2015-07-13T20:18:09ZScience can drive the sustainability of our precious soils, water and oceans<figure><img src="https://images.theconversation.com/files/88196/original/image-20150713-1325-bwrh2x.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C2399%2C1617&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Soil and water are crucial resources that need to be carefully studied and preserved.</span> <span class="attribution"><span class="source">Pete Hill/Flickr</span>, <a class="license" href="http://creativecommons.org/licenses/by-nc/4.0/">CC BY-NC</a></span></figcaption></figure><p><em>This article is part of our series on the <a href="http://www.science.gov.au/scienceGov/news/Pages/PrioritisingAustraliasFuture.aspx">Science and Research Priorities</a> recently announced by the Federal Government. You can read the introduction to the series by Australia’s Chief Scientist, Ian Chubb, <a href="http://theconversation.com/australias-chief-scientist-on-getting-our-research-priorities-right-43833">here</a>.</em></p>
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<p><strong>John Gunn</strong><br>
<em>Chief Executive Officer of the Australian Institute of Marine Science</em></p>
<p>Australia’s soil, water, vegetation and biodiversity, and our vast marine estate, are incredibly valuable national assets. They are fundamentally interconnected components of the continent’s diverse, unique and in many instances fragile ecosystems. </p>
<p>As such, they need to be managed effectively. However, significant gaps in our understanding of each of these components, and the ways in which they interact, need to be addressed to support effective management. </p>
<p>The Australian Government’s <a href="http://www.science.gov.au/scienceGov/ScienceAndResearchPriorities/Pages/default.aspx">Science and Research Priorities</a> recognise these gaps. They call for focusing of our efforts on critical systems such as the Great Barrier Reef, Northern Australia, key agricultural regions, aquifers and urban catchments.</p>
<p>And they identify priority research that will lead to:</p>
<ol>
<li><p>New and integrated national observing systems, technologies and modelling frameworks across the soil-atmosphere-water-marine domains</p></li>
<li><p>Better understanding of sustainable limits for productive use of soil, freshwater, river flows and water rights, terrestrial and marine ecosystems</p></li>
<li><p>Minimising damage to, and developing solutions for, restoration and remediation of, soil, fresh and potable water, urban catchments and marine systems</p></li>
</ol>
<p>The output from investments in these priority areas will be an enhanced capacity for predicting the impacts of global change and of development on natural systems. Importantly it will also provide much needed understanding of the adaptive capacity of terrestrial and marine ecosystems. </p>
<p>This improved evidence base should in turn provide for better decision making strategies in the context of potentially conflicting demands between development, the environment and landscape management.</p>
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<p><strong>Neil McKenzie</strong><br>
<em>Chief Research Scientist, CSIRO Agriculture Flagship at CSIRO</em></p>
<p>Unprecedented demands are being placed on the world’s soil resources, and by 2050 they need to support a 70% increase in food production. However, arable land is finite and major crops are reaching yield plateaux. Better soil management is needed to conserve nutrients, improve water-use and reduce emissions. Climate change also compounds the situation. </p>
<p>Some of Australia’s soil management challenges are immediate and obvious, such as widespread soil acidification of cropping lands. Others are more subtle but just as important, such as erosion and nutrient imbalances. </p>
<p>We need to improve soil management across the continent. This requires new diagnostic systems for determining when and where soil function is being compromised. Australia also needs more effective institutional arrangements for providing information on the condition of our soil resources. </p>
<p>Research investment in these areas will generate large economic returns through increases in agricultural productivity and avoided costs in other soil-dependent industries. This is before we consider the equally large environmental benefits. </p>
<p>At the global scale, improved soil management is needed in nearly all countries. Without these changes, food-price volatility is likely to increase and this will potentially send millions of people into poverty. This is avoidable but only if there is a concerted response by individuals, the private sector and governments.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/88161/original/image-20150713-9480-v2uxms.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/88161/original/image-20150713-9480-v2uxms.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/88161/original/image-20150713-9480-v2uxms.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=398&fit=crop&dpr=1 600w, https://images.theconversation.com/files/88161/original/image-20150713-9480-v2uxms.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=398&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/88161/original/image-20150713-9480-v2uxms.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=398&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/88161/original/image-20150713-9480-v2uxms.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=500&fit=crop&dpr=1 754w, https://images.theconversation.com/files/88161/original/image-20150713-9480-v2uxms.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=500&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/88161/original/image-20150713-9480-v2uxms.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=500&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">Our water resources need careful management, particularly as climate change progresses.</span>
<span class="attribution"><span class="source">Chris Fithall/Flickr</span>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
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<hr>
<p><strong>Paul Bertsch</strong><br>
<em>Deputy Director-Science of Land and Water Flagship CSIRO and Honorary Professor of Soil and Environmental Sciences, University of Queensland</em></p>
<p>The <a href="http://www.science.gov.au/scienceGov/ScienceAndResearchPriorities/Pages/ThePriorities.aspx">Soil and Water research priority</a> represents a critical area of research having significant national and international benefits, outcomes and impacts, as well as being one that differentiates the Australian R&D enterprise from most other global R&D efforts in several ways.</p>
<p>First, specific recognition of the soil resource is not common in national strategies. This is even though soil is a non-renewable resource (on multi-generational time scales) that underpins key life support systems, such as nutrient cycling, carbon sequestration, food, fibre, animal feed and biofuel feedstock production. It also represents one of the earth’s most complex and biologically diverse ecosystems. </p>
<p>A healthy soil resource is also inextricably linked to water quality and quantity as well as serving as a major source of novel antibiotics, anticancer drugs, and enzymes which provide multiple benefits to society; </p>
<p>Secondly, having a research priority that links the soil resource with water resources, including surface and groundwater as well as marine systems, explicitly provides recognition of the controls, interconnectedness and feedbacks between these critical life supporting resources </p>
<p>Finally, combined research priorities amplify the requirement to manage these resources, integrating multiple land uses across natural and managed ecosystems and catchments, that involve agriculture, resource and energy extraction, urban and peri-urban uses, necessarily requiring a full life-cycle consideration of cumulative impacts to soil and water resources, including estuaries and marine systems.</p>
<hr>
<p><strong>Read more in our Science and Research Priorities series</strong></p>
<p><a href="https://theconversation.com/the-future-of-manufacturing-in-australia-is-smart-agile-and-green-43645">The future of manufacturing in Australia is smart, agile and green</a></p>
<p><a href="https://theconversation.com/research-priority-make-australias-health-system-efficient-equitable-and-integrated-43547">Research priority: make Australia’s health system efficient, equitable and integrated</a></p>
<p><a href="http://theconversation.com/australia-could-become-a-leader-in-cybersecurity-research-43716">Australia could become a leader in cybersecurity research</a></p>
<p><a href="http://theconversation.com/on-the-road-research-can-improve-transport-across-australia-43643">On the road: research can improve transport across Australia</a></p><img src="https://counter.theconversation.com/content/43641/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>John Gunn Is the Chief Executive of the Australian Institute of Marine Science (AIMS), one of Australia's Publically Funded Research Agencies. He is also Chair of the National Marine Science Committee, and the Global Ocean Observing System Steering Committee. </span></em></p><p class="fine-print"><em><span>Neil McKenzie works for CSIRO and leads the Soil Research, Development and Extension Strategy which receives contributions primarily from the Rural Industry Research and Development Corporations and the Australian Government Department of Agriculture. As a member of the Intergovernmental Technical Panel on Soils he receives support from the United Nations Food and Agriculture Organization and European Commission. He also leads a project on agricultural development and poverty alleviation funded by the Bill and Melinda Gates Foundation. He is a member of Soil Science Australia and the International Union of Soil Sciences. </span></em></p><p class="fine-print"><em><span>Paul Bertsch works for CSIRO and is a member of the American Chemical Society, American Geophyscal Union, American Association for the Advancement of Science, American Society of Agronomy, International Union of Pure and Applied Chemistry, International Union of Soil Sciences, Geochemical Society, and the Soil Science Society of America.</span></em></p>There will be increasing demands placed on our soil and water in coming years, so we need greater research into how to preserve and maintain these precious resources.John Gunn, Chief Executive Officer, Australian Institute of Marine ScienceNeil McKenzie, Chief Research Scientist, CSIRO Agriculture Flagship, CSIROPaul Bertsch, Deputy Director-Science of Land and Water Flagship CSIRO and Honorary Professor of Soil and Environmental Sciences, University of Queensland, CSIROLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/63832012-04-15T20:37:51Z2012-04-15T20:37:51ZGreat Barrier Reef dying beneath its crown of thorns<figure><img src="https://images.theconversation.com/files/9538/original/rsnscfz2-1334230361.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Another wave is coming: the coral-killing crown of thorns starfish.</span> <span class="attribution"><span class="source">Flickr/<SLIM></span></span></figcaption></figure><p>The Great Barrier Reef is under attack from a range of enemies including climate change effects (coral bleaching, increased severe storms, and ocean acidification), <a href="http://www.reportage-enviro.com/2009/08/a-dark-forecast-for-our-reefs/">pollutant discharge</a> from the land, coastal development, and damage from <a href="http://sitemaker.umich.edu/gc2sec7labgroup3/over-fishing">fishing</a>. </p>
<p>As a result, coral cover is in severe decline, seagrass has declined dramatically in the last few years, while numbers of megafauna including dugong, turtles, sharks and some dolphins have greatly reduced population numbers.</p>
<p>In particular for coral, analysis of coral cover data from about 1960 onwards suggests that cover across the GBR has fallen from about 50% in the 1960s to about 16% now. As yet unpublished estimates by <a href="http://www.nerptropical.edu.au/people/glenn-death">Dr Glenn De'ath</a> and his colleagues suggest that if current trends continue coral cover could be as low as 5% in 20 years.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/9573/original/yzjdg2kd-1334293857.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/9573/original/yzjdg2kd-1334293857.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=445&fit=crop&dpr=1 600w, https://images.theconversation.com/files/9573/original/yzjdg2kd-1334293857.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=445&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/9573/original/yzjdg2kd-1334293857.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=445&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/9573/original/yzjdg2kd-1334293857.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=559&fit=crop&dpr=1 754w, https://images.theconversation.com/files/9573/original/yzjdg2kd-1334293857.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=559&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/9573/original/yzjdg2kd-1334293857.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=559&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<span class="caption">A diver examines a devastated area of the Great Barrier Reef, which is rapidly losing its coral cover.</span>
<span class="attribution"><span class="source">AAP/James Cook University</span></span>
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</figure>
<p>Coral-eating crown of thorns starfish (Acanthaster planci) (COTS) have caused widespread damage to many coral reefs in the Indo-Pacific over the past five decades as population “explosions” have occurred at regular intervals. On the GBR the greatest cause of coral mortality in recent decades is COTS ahead of other major causes such as cyclones, bleaching and coral diseases. COTS were probably the major cause of coral mortality in the period from 1960 to 1985 also but our data is less complete for this period. Kate Osborne and her co-researchers <a href="http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3053361/">found that</a> COTS were responsible for 36.7% of the coral damage above all other causes including storms (33.8%), disease (6.5%), bleaching (5.6%) and unknown or multiple causes (17.4%). </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/9572/original/cwj89d28-1334292814.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/9572/original/cwj89d28-1334292814.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/9572/original/cwj89d28-1334292814.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/9572/original/cwj89d28-1334292814.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/9572/original/cwj89d28-1334292814.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/9572/original/cwj89d28-1334292814.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/9572/original/cwj89d28-1334292814.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Starfish offensives come in waves.</span>
<span class="attribution"><span class="source">AAP/In Touch Media</span></span>
</figcaption>
</figure>
<p>There have been three major periods (“waves”) of COTS outbreaks on the GBR: 1962 – 1976; 1978 – 1991; 1993 – 2005; and it is now accepted that we are at the beginning of the next wave which appears to have started off Cairns in 2009. Each wave started near Cairns and spread through larval dispersion up and down the GBR generally as far as Princess Charlotte Bay in the north and Mackay in the south. If the current wave moves in a similar way we can expect starfish populations to progress throughout the central GBR over the next 10 years or so.</p>
<figure class="align-right ">
<img alt="" src="https://images.theconversation.com/files/9574/original/ckdfbwpr-1334294086.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/9574/original/ckdfbwpr-1334294086.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=799&fit=crop&dpr=1 600w, https://images.theconversation.com/files/9574/original/ckdfbwpr-1334294086.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=799&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/9574/original/ckdfbwpr-1334294086.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=799&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/9574/original/ckdfbwpr-1334294086.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1005&fit=crop&dpr=1 754w, https://images.theconversation.com/files/9574/original/ckdfbwpr-1334294086.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1005&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/9574/original/ckdfbwpr-1334294086.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1005&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Vanishing beauty.</span>
<span class="attribution"><span class="source">AAP/James Cook University</span></span>
</figcaption>
</figure>
<p>The impact of outbreaks on the GBR is a major concern to the multi-billion dollar tourism industry. Over a number of years, there was an outbreak on reefs between Cairns and the Whitsundays which was estimated to cost tourism operators, and the Queensland and Australian Governments about $3 million a year for control measures.</p>
<p>The cause of the outbreaks remains a controversial issue despite years of research. Hypotheses have included that (1) population outbreaks are a natural phenomenon due to the inherently unstable population sizes of highly fecund organisms such as COTS; (2) outbreaks are due to anthropogenic changes to the environment of the starfish with a range of possible anthropogenic causes including: removal of adult and/or juvenile predators; destruction of larval predators e.g. corals, by construction activities on reefs; and larval food supply (phytoplankton) enhancement from nutrient enriched terrestrial run-off.</p>
<p>It is now well established that the large scale outbreaks seen on the GBR since 1962 are most likely to have been caused by nutrient enrichment associated with <a href="http://www.abc.net.au/7.30/content/2004/s1076523.htm">increased discharge</a> of nitrogen and phosphorus from the land due to increased soil erosion and large scale fertiliser use. Increased nutrients drive phytoplankton blooms with increased biomass and also a shift to larger phytoplankton types more palatable to COTS larvae as food. Removal of predators (especially fish) is also implicated as a secondary cause.</p>
<p>There is some evidence that the increase in the area of no-take zones in 2004 has had significant success, as COTS numbers on closed reefs are lower than on reefs open to fishing. Site specific management (through removal) has been successful at a local scale, although it is very labour intensive. With the initiation of the fourth wave of outbreaks now confirmed it is clear that water quality management under the <a href="http://www.reefplan.qld.gov.au/">Reef Water Quality Protection Plan</a> (implemented in 2008) has not had time to prevent further outbreaks. However <a href="http://www.townsvillebulletin.com.au/article/2012/04/13/322211_news.html">further water quality management</a> will be critical to minimise future outbreaks. </p>
<p>In conclusion we can state unequivocally that COTS remain the greatest threat to the coral of the GBR and thus also indirectly to coral reef fish, although obviously of lesser threat to seagrass, dugongs, and some other megafauna. </p>
<p><em>Comments welcome below.</em></p><img src="https://counter.theconversation.com/content/6383/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Jon Brodie receives funding from Australian Government, Queensland Government, WWF, Canegrowers.</span></em></p>The Great Barrier Reef is under attack from a range of enemies including climate change effects (coral bleaching, increased severe storms, and ocean acidification), pollutant discharge from the land, coastal…Jon Brodie, Senior Principal Research Officer , James Cook UniversityLicensed as Creative Commons – attribution, no derivatives.