Legacy nitrogen may prevent achievement of water quality goals in the Gulf of Mexico

K. J. Van Meter, P. Van Cappellen, N. B. Basu

Research output: Contribution to journalArticlepeer-review

136 Scopus citations


In August 2017, the Gulf of Mexico’s hypoxic zone was declared to be the largest ever measured. It has been estimated that a 60% decrease in watershed nitrogen (N) loading may be necessary to adequately reduce eutrophication in the Gulf. However, to date there has been no rigorous assessment of the effect of N legacies on achieving water quality goals. In this study, we show that even if agricultural N use became 100% efficient, it would take decades to meet target N loads due to legacy N within the Mississippi River basin. Our results suggest that both long-term commitment and large-scale changes in agricultural management practices will be necessary to decrease Mississippi N loads and to meet current goals for reducing the size of the Gulf hypoxic zone.

Original languageEnglish (US)
Pages (from-to)427-430
Number of pages4
Issue number6387
StatePublished - Apr 27 2018

All Science Journal Classification (ASJC) codes

  • General

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