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101.
Vegetation Response to Western Juniper Slash Treatments 总被引:2,自引:0,他引:2
The expansion of piñon–juniper woodlands the past 100 years in the western United States has resulted in large scale efforts to kill trees and recover sagebrush steppe rangelands. It is important to evaluate vegetation recovery following woodland control to develop best management practices. In this study, we compared two fuel reduction treatments and a cut-and-leave (CUT) treatment used to control western juniper (Juniperus occidentalis spp. occidentalis Hook.) of the northwestern United States. Treatments were; CUT, cut-and-broadcast burn (BURN), and cut-pile-and-burn the pile (PILE). A randomized complete block design was used with five replicates of each treatment located in a curl leaf mahogany (Cercocarpus ledifolius Nutt. ex Torr. & A. Gray)/mountain big sagebrush (Artemisia tridentata Nutt. spp. vaseyana (Rydb.) Beetle)/Idaho fescue (Festuca idahoensis Elmer) association. In 2010, 4 years after tree control the cover of perennial grasses (PG) [Sandberg’s bluegrass (Poa secunda J. Pres) and large bunchgrasses] were about 4 and 5 % less, respectively, in the BURN (7.1 ± 0.6 %) than the PILE (11.4 ± 2.3 %) and CUT (12.4 ± 1.7 %) treatments (P < 0.0015). In 2010, cover of invasive cheatgrass (Bromus tectorum L.) was greater in the BURN (6.3 ± 1.0 %) and was 50 and 100 % greater than PILE and CUT treatments, respectively. However, the increase in perennial bunchgrass density and cover, despite cheatgrass in the BURN treatment, mean it unlikely that cheatgrass will persist as a major understory component. In the CUT treatment mahogany cover increased 12.5 % and density increased in from 172 ± 25 to 404 ± 123 trees/ha. Burning, killed most or all of the adult mahogany, and mahogany recovery consisted of 100 and 67 % seedlings in the PILE and BURN treatments, respectively. After treatment, juniper presence from untreated small trees (<1 m tall; PILE and CUT treatments) and seedling emergence (all treatments) represented 25–33 % of pre-treatment tree density. To maintain recovery of herbaceous, shrub, and mahogany species additional control of reestablished juniper will be necessary. 相似文献
102.
Neupane A Boxall PC McFarlane BL Pelletier RT 《Journal of environmental management》2007,85(2):471-482
Fire management agencies in Canada are mandated with protecting multiple forest values from wildfire. Deciding where to reduce fire hazard and how to allocate resources and fire suppression efforts requires an understanding of the values-at-risk from wildfire. The protection of recreation infrastructure is often assumed to provide adequate protection of recreation values. We use an expert judgment approach to provide a spatial distribution of recreation values-at-risk in the forested eastern slopes of the Rocky Mountain region of Alberta, Canada. Data were collected in 2004 from 11 land managers responsible for public lands management and wildfire prevention in the region. Expert assessments showed that recreation values were not confined to areas with publicly funded infrastructure. Exploratory spatial analysis of the ratings identified hotspots and cold spots of recreation activity. Maps resulting from these efforts will provide guidance to fire managers in the prioritization of fire management activities. 相似文献