Recovery of Big Sagebrush Following Fire in Southwest Montana |
| |
| Affiliation: | 1. Senior Scientist, Conservation Biology Research, 929 Locust, Missoula, MT 59802;2. Ecologist, Montana Natural Heritage Program, 1515 East Sixth Avenue, Helena, MT 59620;3. Ecology Program Manager, Montana Natural Heritage Program, 1515 East Sixth Avenue, Helena, MT 59620;1. U.S. Geological Survey, Forest and Rangeland Ecosystem Science Center, Boise ID;2. Bureau of Land Management, Boise District Office, Boise ID;1. Graduate Research Assistant, Boise Center Aerospace Laboratory, Idaho State University, Boise, ID 83702, USA;2. Research Professor, Boise Center Aerospace Laboratory, Idaho State University, Boise, ID 83702, USA;3. Rangeland Scientist, Northwest Watershed Research Center, US Department of Agriculture–Agricultural Research Service, Boise, ID 83712, USA;1. Sagebrush Ecosystem Specialist, USDA Natural Resources Conservation Service, West National Technology Support Center, Portland, OR 97232;2. Soil Scientist, USDA Natural Resources Conservation Service, West National Technology Support Center, Portland, OR 97232;3. Research Ecologist, USDA Forest Service, Rocky Mountain Research Station, Reno, NV 89512;4. Ecologist, USDI Bureau of Land Management, Boise, ID 83709;5. Professor Emeritus of Range Science, Oregon State University, Corvallis, OR 97331;1. Research Assistant, Department of Animal and Rangeland Sciences, Oregon State University, La Grande, OR 97850, USA;2. Associate Professor, Agriculture, Veterinary, and Rangeland Sciences, University of Nevada, Reno, NV 89512, USA;3. Biological Scientist, US Department of Agriculture Forest Service, Rocky Mountain Research Station, Corvallis, OR 97331, USA;4. Research Ecologist, US Department of Agriculture Forest Service, Pacific Northwest Research Station, Corvallis, OR 97331, USA;1. PhD Student, Department of Biology, University of New Mexico, Albuquerque, NM 87131, USA;2. Associate Professor, School of Environmental and Forest Sciences, University of Washington, Seattle, WA 98195, USA;3. Affiliate Professor, School of Environmental and Forest Sciences, University of Washington, Seattle, WA 98195, USA;4. Stewardship Coordinator, The Nature Conservancy, Seattle, WA 98101, USA;5. Wildlife Biologist, US Fish and Wildlife Service, Mid-Columbia River National Wildlife Refuge Complex, Burbank, WA 99323, USA;6. Lecturer, School of Interdisciplinary Studies, University of Glasgow, Crichton University Campus, Dumfries, Scotland;7. Ecologist, US Geological Survey, Forest and Rangeland Ecosystem Science Center, Corvallis, OR 97321, USA;8. Research Ecologist, US Geological Survey, Forest and Rangeland Ecosystem Science Center, Corvallis, OR 97321, USA;9. Ecologist, Salstrom & Easterly Eco-logic Botanical Consulting, Bellingham, WA 98229, USA.;10. Botanist, Salstrom & Easterly Eco-logic Botanical Consulting, Bellingham, WA 98229, USA. |
| |
| Abstract: | Fire plays a large role in structuring sagebrush ecosystems; however, we have little knowledge of how vegetation changes with time as succession proceeds from immediate postfire to mature stands. We sampled at 38 sites in southwest Montana dominated by 3 subspecies of big sagebrush (Artemisia tridentata Nutt.). At each site we subjectively located 1 sample plot representing the burned area and an unburned macroplot in similar, adjacent, unburned vegetation. Canopy cover of sagebrush was estimated, and plants were counted in 10 microplots. Age and height of randomly chosen sagebrush plants in each size class were determined from 5 microplots. Average postfire time to full recovery of mountain big sagebrush (ssp. vasseyana [Rydb.] Beetle) canopy cover was 32 years, shorter for basin (ssp. tridentata) and much longer for Wyoming (ssp. wyomingensis Beetle & Young) big sagebrush. Height recovered at similar rates. There was no difference in canopy cover or height recovery between prescribed fires and wildfires in stands of mountain big sagebrush. We found no relationship between mountain big sagebrush canopy cover recovery and annual precipitation, heat load, or soil texture. Nearly all unburned sagebrush macroplots were uneven-aged, indicating that recruitment was not limited to immediate postfire conditions in any of the subspecies. Average canopy cover of three-tip sagebrush (A. tripartita Rydb.) did not increase following fire, and many three-tip sagebrush plants established from seed instead of sprouting. Our results suggest that the majority of presettlement mountain big sagebrush stands would have been in early to midseral condition in southwest Montana assuming a mean fire interval of 25 years. Only long fire-return intervals will allow stands dominated by Wyoming big sagebrush to remain on the landscape in our study area. We speculate that effects of site-specific factors conducive to sagebrush recovery are small compared to stochastic effects such as fire. |
| |
| Keywords: | |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
