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Nitrogen Risk Assessment

Photo of arid shrubland ecosystem, Joshua Tree NP, California. Photo of subalpine meadow ecosystem in North Cascades NP, Washington. Photo of a high elevation lake in Glacier NP, Montana. Photo of wetland ecosystem in Everglades NP, Florida.
Some ecosystems, including arid shrublands, are sensitive to nutrient enrichment from atmospheric nitrogen deposition.

Some ecosystems in parks, such as arid shrublands, subalpine meadows, remote high elevation lakes, and wetlands, are sensitive to the effects of nutrient enrichment from atmospheric nitrogen deposition. Nitrogen deposition results from nitrogen oxides emitted from powerplants, vehicles, and industry, and from ammonia emitted from agricultural activities. When added to natural ecosystems, nitrogen deposition can affect biodiversity in plant communities and disrupt nutrient cycling.

Explore which parks are most at risk from nitrogen deposition through a series of reports (listed below) that rank the relative sensitivity of about 270 parks organized into 32 networks. The ranking considers 1) nitrogen pollutant exposure, 2) ecosystem sensitivity, and 3) park protection mandates. The main report provides background for the project, describes the assessment methods, and summarizes ranking results.

An interactive mapper is also available to visualize relative nitrogen pollutant exposure, ecosystem sensitivity, park protection mandates, and overall park and network risk.

Main Report

Inventory & Monitoring Network Reports

Related Links

Last Updated: February 25, 2015