Globally, many rivers are experiencing declining water quality, for example, with altered
levels of sediments, salts, and nutrients. Effective water quality management requires a …

The Soil and Water Assessment Tool (SWAT) model is a continuation of nearly 30 years of
modeling efforts conducted by the USDA Agricultural Research Service (ARS). SWAT has …

Although water constitutes 71% of the earth's surface, only 0.3% of it is available as fresh
water for human use. Moreover, the quality of fresh water in ground and surface systems is …

In the mid-1800s, the agricultural chemist Justus von Liebig demonstrated strong positive
relationships between soil nutrient supplies and the growth yields of terrestrial plants, and it …

This book is open access under a CC BY-NC 4.0 license. This revised, updated textbook
presents a systems approach to the planning, management, and operation of water …

Denitrification is a critical process regulating the removal of bioavailable nitrogen (N) from
natural and human‐altered systems. While it has been extensively studied in terrestrial …

Estimates of non-point source (NPS) contribution to total water pollution in China range up to
81% for nitrogen and to 93% for phosphorus. We believe these values are too high …

The past few decades have seen a massive increase in coastal eutrophication globally,
leading to widespread hypoxia and anoxia, habitat degradation, alteration of food-web …

Seasonal hypoxia in the northern Gulf of Mexico has been linked to increased nitrogen
fluxes from the Mississippi and Atchafalaya River Basins, though recent evidence shows that …

Increased loading of nitrogen (N) and phosphorus (P) from agricultural and urban
intensification has led to severe degradation of inland and coastal waters. Lakes, reservoirs …