Nitrogen mineralization across an atmospheric nitrogen deposition gradient in Southern California desertsAuthor(s): L.E. Rao; D.R. Parker; Andrzej Bytnerowicz; E.B. Allen
Source: Journal of Arid Environments. 73(10): 920-930
Publication Series: Scientific Journal (JRNL)
View PDF (809.0 KB)
Dry nitrogen deposition is common in arid ecosystems near urban and agricultural centers, yet its impacts on natural environments are relatively understudied. We examined the effects of N deposition on soil N mineralization across a depositional gradient at Joshua Tree National Park. We hypothesized that N deposition affects N mineralization by promoting exotic grass invasion and increasing soil carbon and nitrogen. These relationships were tested through a laboratory incubation on soils collected from sixteen sites where atmospheric N, soil characteristics, and annual vegetation were measured. Mineralization parameters modeled using the Gompertz model were compared to soil C, soil N, estimated soil N from deposition, and percent cover of exotic and native annuals. Calculated soil N from deposition was directly correlated with measured soil C and N and decreasing C:N ratios, which were associated with increased total amounts of mineralized N. However, no effects of soil C or N, and thus N deposition, were observed on mineralization rates. Exotic grasses, but not native forbs or total annual cover, increased with soil C, soil N, and total mineralized N, suggesting that exotic grasses and N deposition are correlated and associated with increasing total C and N in the interspace soils at polluted locations.
- You may send email to email@example.com to request a hard copy of this publication.
- (Please specify exactly which publication you are requesting and your mailing address.)
- We recommend that you also print this page and attach it to the printout of the article, to retain the full citation information.
- This article was written and prepared by U.S. Government employees on official time, and is therefore in the public domain.
CitationRao, L.E.; Parker, D.R.; Bytnerowicz, A.; Allen, E.B. 2009. Nitrogen mineralization across an atmospheric nitrogen deposition gradient in Southern California deserts. Journal of Arid Environments. 73(10): 920-930.
KeywordsDecomposition, Invasive grass, Mineralization model, Mojave, Nutrients, Sonoran
- Impacts of atmospheric nitrogen deposition on vegetation and soils in Joshua Tree National Park
- Soil resources influence vegetation and response to fire and fire-surrogate treatments in Sagebrush-Steppe Ecosystems
- Using fire risk and species loss to set critical loads for nitrogen deposition in southern California shrublands
XML: View XML