Skip to Main Content
Soil carbon and nutrient pools in Douglas-fir plantations 5 years after manipulating biomass and competing vegetation in the Pacific NortwestAuthor(s): Robert A. Slesak; Stephen H. Schoenholtz; Timothy B. Harrington
Source: Forest Ecology and Management. 262: 1722-1728
Publication Series: Scientific Journal (JRNL)
Station: Pacific Northwest Research Station
PDF: Download Publication (678.93 KB)
DescriptionWe assessed changes in mineral soil total carbon (C) and nutrient (exchangeable Ca, K, Mg, and total N) pools to 60 cm depth 5 years after manipulating biomass and competing vegetation at two contrasting Douglas-fir plantations (Matlock, WA, and Molalla, OR). Biomass treatments included whole-tree (WT) and bole-only (BO) harvest, and competing vegetation control (VC) treatments were applied as either initial or annual herbicide applications. There were main effects of biomass removal and VC on the absolute change in soil pools of some elements at both sites, but significant effects were more prevalent at the lower soil quality Matlock site than the Molalla site, and were generally confined to the top 15 cm of soil. In all cases, treatment effects were associated with increases in C and nutrients following BO and initial VC treatments combined with little change in soil pools following WT and annual VC treatments. At the Matlock site, total soil pools (0-60 cm) of C, N, and Ca significantly increased in the BO and initial VC treatments, and Mg increased and K decreased regardless of treatment. At the Molalla site, soil C and nutrient pools did not change in response to treatments, but total soil Mg increased in all treatments during the study period. Correlation analyses indicated little influence of soil nutrient pools on early growth at Matlock likely because soil water is more limiting than nutrient availability at that site, but vegetation growth was correlated to nutrient pools at Molalla indicating changes in pools associated with harvesting and treatment could influence crop development in the future. These early results indicate low potential for intensive management practices to reduce mineral soil pools of C and nutrients, but there is uncertainty on the long-term growth response because treatments may have influenced nutrient storage in pools other than mineral soil.
- Visit PNW's Publication Request Page to request a hard copy of this publication.
- 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.
CitationSlesak, Robert A.; Schoenholtz, Stephen H.; Harrington, Timothy B. 2011. Soil carbon and nutrient pools in Douglas-fir plantations 5 years after manipulating biomass and competing vegetation in the Pacific Nortwest. Forest Ecology and Management. 262: 1722-1728.
Keywordsforest biomass energy, slash manipulation, vegetation manipulation, Long Term Soil Productivity, soil water limitation
- Soil phosphorus fractions vary with harvest intensity and vegetation control at two contrasting Douglas-fir sites in the Pacific northwest
- The Fall River Long-Term Site Productivity study in coastal Washington: site characteristics, methods, and biomass and carbon and nitrogen stores before and after harvest.
- Effects of intensive management practices on 10-year Douglas-fir growth, soil nutrient pools, and vegetation communities in the Pacific Northwest, USA
XML: View XML