This report addresses the following two questions: - What are the loads (flux) of nutrients
transported from the Mississippi-Atchafalaya River Basin to the Gulf of Mexico, and where do …

Glyphosate use in the United States increased from less than 5,000 to more than 80,000 metric
tons/yr between 1987 and 2007. Glyphosate is popular due to its ease of use on soybean…

Historical streamflow and concentration data were used in regression models to estimate
the annual flux of nitrogen (N) to the Gulf of Mexico and to determine where the nitrogen …

Current and historical data show that nitrogen concentrations and flux in the Mississippi
River Basin have increased significantly during the past 100 years. Most of the increase …

The use of glyphosate has increased rapidly, and there is limited understanding of its
environmental fate. The objective of this study was to document the occurrence of glyphosate and …

Fungicides are used to prevent foliar diseases on a wide range of vegetable, field, fruit, and
ornamental crops. They are generally more effective as protective rather than curative …

Nitrogen from the Mississippi River Basin is believed to be at least partly responsible for the
large zone of oxygen-depleted water that develops in the Gulf of Mexico each summer. …

A study was conducted to determine whether NO 3 stable isotopes (δ 15 N and δ 18 O), at
natural abundance levels, could discriminate among NO 3 sources from sites with different …

Vernal pools are sensitive environments that provide critical habitat for many species,
including amphibians. These small water bodies are not always protected by pesticide label …

US Geological Survey has monitored streamflow and water quality systematically in the
Mississippi-Atchafalaya River Basin (MARB) for more than five decades. This report provides …