Skip to page content
USDA Forest Service

Research & Development Treesearch

Treesearch Home
About Treesearch
Contact Us
Research & Development
Forest Products Lab
International Institute of Tropical Forestry
Pacific Northwest
Pacific Southwest
Rocky Mountain
Southern Research Station
Help - We Participate  Government Made Easy

Global Forest Information Service

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

(202) 205-8333

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

Publication Information

View PDF (838 KB bytes)

Title: Respiration , nitrogen fixation, and mineralizable nitrogen spatial and temporal patterns within two Oregon Douglas-fir stands.

Author: Hope, Sharon M.; Li, Ching-Yan.;

Date: 1997

Source: Canadian Journal of Forest Research. 27: 501-509

Publication Series: Scientific Journal (JRNL)

Description: Substrate respiration, mineralizable nitrogen, and nitrogen fixation rates, substrate moisture,content, and temperature were measured in trenched and undisturbed plots within two western Oregon Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) stands. The stands represent two different environments and ages. Woods Creek, the site of the lower elevation mature 70-year-old stand, is located in the Willamette Valley near Philomath, Oregon. The H.J. Andrews Forest, site of the higher elevation old-growth stand, lies on the western slopes of the Oregon Cascades. Mineralizable nitrogen rates were 1.3 times higher at Woods Creek than at the H.J. Andrews Forest; nitrogen fixation was 1.3 times greater at Woods Creek than at the old-growth H.J. Andrews stand. Litter evolved more CO2 and yielded more than 3 times the mineralizab!e nitrogen rates of logs and soils. Woods Creek logs had significantly higher nitrogen fixation than mineral soils (2 < 0.001); there was greater nitrogen fixation in logs and soils sampled at 0—4 cm than at 4-20 cm (p < 0.03). At the old-growth H.J. Andrews Forest site, nitrogen fixation was significantly greater in logs than in soils (2 < 0.001). Nitrogen fixation tended to be higher in samples from 0 to 4 cm within logs arid mineral soils than in samples from 4 to 20 cm.There were no statistical differences in mineralizable nitrogen at the H.J. Andrews Forest between logs and mineral soils either by type or by depth at the p < 0.05 level. Neither site yielded a statistically significant difference in mineralizable nitrogen between trenched log and soil plots and nontrenched log and soil plots. Mineralizable nitrogen declined with.depth, but this pattern was only statistically significant at Woods Creek (2 < 0.005).

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.



Hope, Sharon M.; Li, Ching-Yan. 1997. Respiration , nitrogen fixation, and mineralizable nitrogen spatial and temporal patterns within two Oregon Douglas-fir stands. Canadian Journal of Forest Research. 27: 501-509


 [ 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.