A new accounting of nitrogen pollution in the Mississippi-Atchafalaya River Basin (MARB) reveals a significant decline in recent decades, suggesting positive momentum for water quality goals in local watersheds and the Gulf of Mexico. Surprisingly, the University of Illinois Urbana-Champaign-led study doesn't credit the change to reduced fertilizer application, but instead to cleaner air and more efficient nitrogen uptake by modern corn hybrids. The research is published in the journal Ocean-Land-Atmosphere Research.