Animal waste and nitrogen-based agricultural fertilizers contribute to nitrate runoff, which ends up in creeks, streams, rain and, eventually, water systems. Nitrate, that mix of nitrogen and oxygen, can cause serious health problems if it’s too concentrated.
The best defense is filtering, which forests are great at doing. But a new study from the U.S. Department of Agriculture’s Forest Service suggests forests are falling behind, and heavy rains brought on by climate change are making it worse.