Assessment of nitrogen deposition effects and empirical critical loads of nitrogen for ecoregions of the United States
By: editors, L.H. Pardo, M.J. Robin-Abbott, C.T. Driscoll
Contributors: United States. Forest Service. Northern Research Station
Series: General technical report NRS -- 80; General technical report NRS -- 80.
Publisher: U.S. Dept. of Agriculture, Forest Service, Northern Research Station
Published: 2011
Place of publication: Newtown Square, PA
Language: eng
Number of pages: 291
Subjects: Water; Nitrogen compounds; Ecology; Atmospheric deposition; Pollution; Air
Description: This report synthesizes  current research relating atmospheric nitrogen (N) deposition to effects on terrestrial and aquatic ecosystems in the United States and to identify empirical critical loads for atmospheric N deposition. The report evaluates the following receptors: freshwater diatoms, mycorrhizal fungi and other soil microbes, lichens, herbaceous plants, shrubs, and trees. The main responses reported fell into two categories: (1) biogeochemical; and (2) individual species, population, and community responses. The range of critical loads for nutrient N reported for U.S. ecoregions, inland surface waters, and freshwater wetlands is presented. This range spans the range of N deposition observed over most of the country. The empirical critical loads for N tend to increase in the following sequence for four different life forms: diatoms, lichens and bryophytes, mycorrhizal fungi, herbaceous plants, shrubs, trees.
Notes: "May 2011"--P. [2] of cover.

Includes bibliographical references.

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