by Sarah Hansen
Nitrogen pollution in the Chesapeake Bay became a serious concern in the mid-20th century after the advent of nitrogen-rich chemical fertilizers. Bay restoration efforts have reduced nitrogen pollution somewhat, but achieving healthy nitrogen levels in the Bay is still a long way off. Croplands remain an important source of the nitrogen that pollutes Chesapeake Bay.
Don Weller, senior scientist at the Smithsonian Environmental Research Center, and his colleague Matthew Baker, associate professor of geography and environmental systems at the University of Maryland, Baltimore County, report in a new study that just over half the nitrogen from croplands might never reach the Bay—if all crop fields were protected by streamside forests and wetlands.