20 hotspots to start fixing nitrogen pollution in agriculture
Nitrogen pollution is one of agriculture’s biggest and most intractable problems. Crops can’t grow without the critical nutrient, and because sources of nitrogen are easy to come by—synthetic fertilizer is cheap and manure from large animal agriculture operations is plentiful—farmers often apply too much, to try to ensure the highest yields. Because plants can’t use it all, the excess makes its way into groundwater and washes into waterways where it contaminates drinking water and creates vast dead zones in oceans and lakes. … California’s largest hotspot unsurprisingly includes 21 counties that cover the Central Valley, America’s produce capital.