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Causes and consequences of herbivory on prairie lupine (Lupinus lepidus) in early primary succession
Primary succession, the formation and change of ecological communities in locations initially lacking organisms or other biological materials, has been an important research focus for at least a century (Cowles 1899; Griggs 1933; Eggler 1941; Crocker and Major 1955; Eggler 1959; Miles and Walton 1993; Waker and del Moral 2003). At approximately 60 km2, primary successional surfaces at Mount St. Helens occupy a minor proportion of the blast area, yet they are arguably the most compelling. The cataclysmic genesis of this landscape, its utter sterilization, and the drama of its reclamation by...AuthorsJohn G. Bishop, William F. Fagan, John G. Schade, Charles M. CrisafulliSourceIn: Ecological Responses to the 1980 Eruption of Mount St. Helens: 151-161Year2005- This document reviews existing and proposed protocols used to monitor stream ecosystem conditions and responses to land management activities in the Pacific Northwest. Because of recent work aimed at improving the utility of habitat survey and fish abundance assessment methods, this review focuses on current (since 1993) monitoring efforts that assess stream habitat conditions and juvenile fish use. It does not focus on protocols specifically intended to monitor trends in fish populations for salmon recovery efforts, other fish life-history stages (e.g., salmonid smolt monitoring or...AuthorsScott A. Stolnack, Mason Bryant, Robert C. WissmarSourceGen. Tech. Rep. PNW-GTR-625. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 36 pYear2005
- Air-quality monitoring in the United States is typically focused on urban areas even though the detrimental effects of pollution often extend into surrounding ecosystems. The purpose of this study was to construct a model, based upon epiphytic macrolichen community data, to indicate air-quality and climate in forested areas throughout the greater Central Valley of California (USA). The structure of epiphytic lichen communities is widely recognized as an effective biological indicator of air-quality as sensitivities to common anthropogenic pollutants vary by species. We used nonmetric...AuthorsSarah Jovan, Bruce McCuneKeywordsSourceEcological Applications. 15(5): 1712–1726Year2005
Canopy arthropod response to density and distribution of green trees retained after partial harvest.
We measured canopy arthropod responses to six contrasting green-tree retention treatments at six locations (blocks) in western Oregon and Washington as part of the Demonstration of Ecosystem Management Options (DEMO) study. Treatments were 100% retention (uncut), 75% retention with three 1-ha harvested gaps, 40% dispersed retention, 40% aggregated retention with five 1-ha uncut aggregates, 15% dispersed retention, and 15% aggregated retention with two 1-ha uncut aggregates. Arthropods were sampled from upper, mid-, and lower crown levels of one overstory Douglas-fir (Pseudotsuga menziesti...AuthorsTimothy D. Schowalter, Yanli Zhang, Robert ProgarKeywordsSourceEcological Applications. 15(5); 1594-1603Year2005- Forest managers face an array of prickly, seemingly intractable environmental problems. They have traditionally turned to the biophysical sciences to help gauge potential management effects, weigh alternatives, and set priorities. Over the past several decades, forest managers have watched management plans disintegrate in the face of grassroots-level protests, quarrels between regional-level regulatory organisations, and even national-level policy disputes. At whatever level, the controversies have a common denominator: they involve conflicting human values, attitudes and behaviors. With...AuthorsHeidi Bigler-ColeKeywordsSourceIn: Proceedings 6th National Conference of the Australian Forest History Society Inc, p. 35-46Year2005
- A hierarchical spatial framework for large-scale, long-term forest landscape planning is presented along with example policy analyses for a 560,000 ha area of the Oregon Coast Range. The modeling framework suggests utilizing the detail provided by satellite imagery to track forest vegetation condition and for representation of fine-scale features, such as riparian areas. Spatial data are then aggregated up to management units, where forest management decisions are simulated. Management units may also be aggregated into harvest blocks to closer emulate management behavior. Land allocations,...AuthorsPete Bettinger, Marie Lennette, K. Norman Johnson, Thomas A. SpiesKeywordsSourceEcological Modeling. 182: 25-48Year2005
- This report reviews the extensive and growing literature on the concept and application of adaptive management. Adaptive management is a central element of the Northwest Forest Plan and there is a need for an informed understanding of the key theories, concepts, and frameworks upon which it is founded. Literature from a diverse range of fields including social learning, risk and uncertainty, and institutional analysis was reviewed, particularly as it related to application in an adaptive management context. The review identifies opportunities as well as barriers that adaptive management...AuthorsGeorge H. Stankey, Roger N. Clark, Bernard BormannKeywordsSourceGen. Tech. Rep. PNW-GTR-654. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 73 pYear2005
- Sierra Nevada forests have high understory species richness yet we do not know which site factors influence herb and shrub distribution or abundance. We examined the understory of an old-growth mixed-conifer Sierran forest and its distribution in relation to microsite conditions. The forest has high species richness (98 species sampled), most of which are herbs with sparse cover and relatively equal abundance. Shrub cover is highly concentrated in discrete patches. Using overstory tree cover and microsite environmental conditions, four habitats were identified; tree cluster, partial...AuthorsMalcolm P. North, Brian Oakley, Rob Fiegener, Andrew Gray, Michael BarbourKeywordsSourcePlant Ecology. 177: 13–24Year2005
- Rising wildfire suppression expenditures on public land in the United States have led to increased scrutiny of wildfire management practices. One area that has received particular attention is the Forest Service's increasing reliance on contract fire crews. Because a contract crew rate includes several costs that are not included in the wage costs of a Forest Service crew, it is difficult to determine if this increasing reliance on contract fire crews increases or decreases wildfire suppression costs. The full cost of 33 Forest Service type II fire crews dispatched during the 2003 fire...AuthorsGeoffrey DonovanKeywordsSourceWestern Journal of Applied Science 20(4):233-239Year2005
- The Information Age is here, and technology has a large and important role in gathering, compiling, and synthesizing data. The old adage of analyzing wildlife data over "time and space" today entails using technologies to help gather, compile, and synthesize remotely sensed information, and to integrate results into research, monitoring and evaluation. Thus, resource managers must understand how to use these technologies, especially for evaluating and assessing land and resource conditions at different scales, such as site, watershed, sub-basin, and basin levels. This chapter explores...AuthorsThomas A. O'Neil, Pete Bettinger, Bruce G. Marcot, B. Wayne Luscombe, Gregory T. Koeln, Howard J. Bruner, Charley Barrett, Jennifer A. Pollock, Susan BernatasSourceThe Wildlife Society: 418-447Year2005