Variable impacts of contemporary versus legacy agricultural phosphorus on US river water quality.

ABSTRACT: Phosphorus (P) fertilizer has contributed to the eutrophication of freshwater ecosystems. Watershed-based conservation programs aiming to reduce external P loading to surface waters have not resulted in significant water-quality improvements. One factor that can help explain the lack of water-quality response is remobilization of accumulated legacy (historical) P within the terrestrial-aquatic continuum, which can obscure the beneficial impacts of current conservation efforts. We examined how contemporary river P trends (between 1992 and 2012) responded to estimated changes in contemporary agricultural P balances [(fertilizer + manure inputs)-crop uptake and harvest removal] for 143 watersheds in the conterminous United States, while also developing a proxy estimate of legacy P contributio

SUBMITTER: Stackpoole SM 

PROVIDER: S-EPMC6789928 | biostudies-literature | 2019 Oct

REPOSITORIES: biostudies-literature