Skip to page content
USDA Forest Service
  
Treesearch

Research & Development Treesearch

 
Treesearch Home
About Treesearch
Contact Us
Research & Development
Forest Products Lab
International Institute of Tropical Forestry
Northern
Pacific Northwest
Pacific Southwest
Rocky Mountain
Southern Research Station
Help
 

Science.gov - We Participate


USA.gov  Government Made Easy


Global Forest Information Service

US Forest Service
P.O. Box 96090
Washington, D.C.
20090-6090

(202) 205-8333

You are here: Home / Search / Publication Information
Bookmark and Share

Publication Information

View PDF (660 KB bytes)

Title: Nitrogen saturation in a high elevation New England spruce-fir stand

Author: McNulty, Steven G.; Aber, John D.; Newman, Steven D.;

Date: 1994

Source: Forest Ecology and Management 84(1994) 109- 121

Publication Series: Miscellaneous Publication

Description: High rates of nitrogen (N) deposition were first postulated as a cause of N saturation (i.e. the availability of NH-N and NO3-N in excess of total combined plant and microbial nutritional demand) and spruce mortality during the1980s. To test this hypothesis, N addition plots were established in 1988, in a high elevation spruce-fir forest in southeastern Vermont, an area of relatively low N deposition (5.4 kg N bulk deposition ha-1 year-1). To test how the form of applied N may influence forest growth and N-cycling, four replicated treatment plots received either NH4-N,NaNO3-N or a combination of both N forms at rates ranging from 15.7 to 31.4 kg N ha-1 year-1. The N additions were applied in threeequal doses each year between June and August from 1988 to 1994. In addition to N treatments, two control plots were also established. Between 1988 and 1990, annual in situ net N mineralization and net nitrification in the forest floor, litterfall and forest floor mass and elemental concentration, foliar elemental concentration, and basal area growth by species were measured on each plot. In July 1994, basal area growth by species, net N mineralization potential and net nitrification potential inthe forest floor. and foliar and forest floor elemental concentration were again measured on all plots. Inter-treatment and intra-tnat- merit basal area growth changed substantially between 1988 and 1994. Spruce, fir. and birch treeson the N addition plots receiving< 20 kg N ha-1 year-1 had the highest rate of growth between 1988 and 1990and then had the highest rate of decline between 1991 and 1994. Spruce, fir, and birch trees on the N addition plots receiving > 25 kg N ha-1 year-1 showed moderate rates of decline from 1988 to 1994. Numerous birch and maple sprouts were noted on the sites with the highest rates of decline, but no spruce or fir seedlings were observed. In July 1994, net N mineralization potential was highest on the control plots and net nitrification potential of the forest floor was highest on the plots receiving 15.7 kg N ha-1 year-1. A strong positive correlation existed between forest floor %N and net nitrification potential. Foliar %N was positively con-elated with added N and negatively correlated with the change in net basal area growth. Foliar Ca:AI concenvations may also be negatively related to changes in net basal area growth. Our results suggest that N saturation has caused foliar nutrient imbalances on the N addition plots, and that the stands maybe changing in species composition and structure. No long-term effects of N-form additions on N saturation and forest health were observed.

Publication Notes:

  • 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.
  • You may send email to pubrequest@fs.fed.us to request a hard copy of this publication. (Please specify exactly which publication you are requesting and your mailing address.)

XML: View XML

Citation:


McNulty, Steven G.; Aber, John D.; Newman, Steven D. 1994. Nitrogen saturation in a high elevation New England spruce-fir stand. Forest Ecology and Management 84(1994) 109- 121

 


 [ Get Acrobat ]  Get the latest version of the Adobe Acrobat reader or Acrobat Reader for Windows with Search and Accessibility

USDA logo which links to the department's national site. Forest Service logo which links to the agency's national site.