Mayflies and stone flies are extremely vulnerable to water pollution, which has implications for the larger food chain.
The salt in the sea has built up over billions of years – but it wouldn't have got there without freshwater rivers and streams.
The Trump administration wants to end federal protection under the Clean Water Act for many small streams and wetlands. But as a geoscientist explains, these are critical parts of large river systems.
Pharmaceuticals were found in every invertebrate sampled from six Melbourne streams - including a waterway in a national park.
When people form local networks to take care of resources such as drinking water, they strengthen their communities. Technology can support these efforts and promote learning and innovation.