Why are rivers at risk?
Why are rivers at risk? Dams and channelization destroy habitats, cut rivers off from their floodplains, and alter the natural ebb and flow on which a river's plants and animals depend. Invasive species crowd rivers' banks, drive out their native fishes, and choke their courses.
What is a major threat to rivers?
The creation of dams and water-diversion systems blocks migration routes for fish and disrupts habitats. Water withdrawal for human use shrinks and degrades habitats. Runoff from agricultural and urban areas hurts water quality. Draining of wetlands for development depletes habitats.
How do you know if a river is healthy?
With abiotic factors, checking the water chemistry such as the water temperature and dissolved oxygen (DO2) is a great way to determine the health of a river. A higher temperature and lower DO2 makes a difficult environment to sustain a diversity of fish and aquatic organisms.