Nitrate pollution in rivers linked to dry climates, not just human activity

Nitrate, a chemical compound of oxygen and nitrogen often used in farm fertilizers, can rise to toxic levels in surrounding water under very dry conditions. This relationship has traditionally been attributed to agricultural runoff or human waste in the environment, but new research led by scientists at Penn State shows that a hot and dry climate elevates concentrations of nitrate in rivers and streams, even in areas without urban or agricultural development.