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GLOBAL BIOGEOCHEMICAL CYCLES,
VOL. 17, NO. 4,
1115,
doi:10.1029/2003GB002060,
2003
Global modeling of the fate of nitrogen from point and nonpoint sources in soils, groundwater, and surface water
G. Van Drecht
Netherlands Environmental Assessment Agency, National Institute for Public Health and the Environment, Bilthoven, Netherlands
A. F. Bouwman
Netherlands Environmental Assessment Agency, National Institute for Public Health and the Environment, Bilthoven, Netherlands
J. M. Knoop
Netherlands Environmental Assessment Agency, National Institute for Public Health and the Environment, Bilthoven, Netherlands
A. H. W. Beusen
Netherlands Environmental Assessment Agency, National Institute for Public Health and the Environment, Bilthoven, Netherlands
C. R. Meinardi
Netherlands Environmental Assessment Agency, National Institute for Public Health and the Environment, Bilthoven, Netherlands
Abstract
We present a global model that describes the fate of nitrogen (N) from point and nonpoint sources in the hydrological system
up to the river mouths at the 0.5° by 0.5° spatial and annual temporal resolution. Estimates for point sources are based on
population densities, per capita human N emissions, and data on sanitation coverage and wastewater treatment. For nonpoint
sources, we use spatial information on land use, climate, hydrology, geology, and soils, combined with data on N inputs (fertilizers
and animal manure, biological N fixation, and atmospheric deposition), and outputs (N removal in harvested agricultural products,
ammonia emissions). Denitrification in the root zone and nitrate leaching to groundwater are calculated with a model that
combines the effect of temperature, crop type, soil properties, and hydrological conditions. The nitrate concentration of
the outflow for shallow and deep groundwater layers is based on historical inputs of fertilizer N and the effects of residence
time and denitrification. In-stream N retention is based on a global estimate of 30% of the N discharged to surface water.
Calculated and reported total N concentrations of discharge near the river outlet agree fairly well. However, our model systematically
overestimates total N concentrations for river basins with mean annual temperature >0°C.
Received 5
March
2003;
accepted 3
September
2003;
published 13
December
2003.
Index Terms: 1615 Global Change: Biogeochemical processes (4805); 1803 Hydrology: Anthropogenic effects; 1871 Hydrology: Surface water quality; 1831 Hydrology: Groundwater quality.
Read Full Article (file size: 3997836 bytes) Cited by
Citation: Van Drecht, G., A. F. Bouwman, J. M. Knoop, A. H. W. Beusen, and C. R. Meinardi
(2003),
Global modeling of the fate of nitrogen from point and nonpoint sources in soils, groundwater, and surface water,
Global Biogeochem. Cycles,
17(4),
1115,
doi:10.1029/2003GB002060.
Copyright 2003 by the American Geophysical Union.
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