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Prescribed Fire (prescribed + fire)
Selected AbstractsEffects of Prescribed Fire and Season of Burn on Recruitment of the Invasive Exotic Plant, Potentilla recta, in a Semiarid GrasslandRESTORATION ECOLOGY, Issue 4 2003Peter Lesica Abstract Prescribed fire is often used to restore grassland systems to presettlement conditions; however, fire also has the potential to facilitate the invasion of exotic plants. Managers of wildlands and nature reserves must decide whether and how to apply prescribed burning to the best advantage in the face of this dilemma. Herbicide is also used to control exotic plants, but interactions between fire and herbicides have not been well studied. Potentilla recta is an exotic plant invading Dancing Prairie Preserve in northwest Montana. We used a complete factorial design with all combinations of spring burn, fall burn, no burn, picloram herbicide, and no herbicide to determine the effects of fire, season of burn, and their interaction with herbicide on the recruitment and population growth of P. recta over a 5-year period. Recruitment of P. recta was higher in burn plots compared with controls the first year after the fire, but this did not lead to significant population growth in subsequent years, possibly due to drier than normal conditions that occurred most years of the study. Effect of season of burn was variable among years but was higher in fall compared with spring burn plots across all years. Herbicide effectively eliminated P. recta from sample plots for 3,5 years. By the end of the study density of P. recta was greater in herbicide plots that were burned than those that were not. Results suggest that prescribed fire will enhance germination of P. recta, but this will not always lead to increased population growth. Prescribed fire may reduce the long-term efficacy of herbicide applied to control P. recta and will be most beneficial at Dancing Prairie when conducted in the spring rather than the fall. Results of prescribed fire on exotic plant invasions in semiarid environments will be difficult to predict because they are strongly dependent on stochastic climatic events. [source] The effects of green tree retention and subsequent prescribed burning on ground beetles (Coleoptera: Carabidae) in boreal pine-dominated forestsECOGRAPHY, Issue 5 2006Petri Martikainen We studied how two methods to promote biodiversity in managed forests, i.e. green tree retention and prescribed fire, affect the assemblages of carabid beetles. Our experiment consisted of 24 study sites, each 3,5 ha in size, which had been prepared according to factorial design. Each of the eight treatment combinations determined by the two factors explored , tree retention level (0, 10, 50 m3/ha,1 and uncut controls) and prescribed use of fire (yes/no) , was replicated three times. We sampled carabids using pitfall traps one year after the treatments. Significantly more individuals were caught in most of the burned sites, but this difference was partially reflective of the trap-catches of Pterostichus adstrictus. The fire did not increase no. of P. adstrictus in the uncut sites as much as in the other sites. Species richness was significantly affected by both factors, being higher in the burned than in the unburned sites and in the harvested than in the unharvested sites. Many species were concentrated in the groups of retention trees in the burned sites, but only a few were in the unburned sites. The species turnover was greater in the burned than in the unburned sites, as indicated by the NMDS ordinations. Greater numbers of smaller sized species and proportion of brachypterous species were present in the burned sites. Fire-favored species, and also the majority of other species that prefer open habitats were more abundantly caught in the burned sites than in the unburned sites. Dead wood or logging waste around the traps did not correlate with the occurrence of species. We conclude that carabids are well adapted to disturbances, and that frequent use of prescribed fire is essential for the maintenance of natural assemblages of carabid beetles in the boreal forest. Small retention tree groups can not maintain assemblages of uncut forest, but they can be important by providing food, shelter and breeding sites for many species, particularly in the burned sites. [source] Recovery of soil microbial community structure after fire in a sagebrush-grassland ecosystemLAND DEGRADATION AND DEVELOPMENT, Issue 5 2010S. R. Dangi Abstract Recovery of the soil microbial community after fire in a sagebrush-grassland ecosystem was examined using a chronosequence of four sites ranging in time since fire from 3,39 years. The successional stage communities examined included Recent Burn (3,years since fire, ysf), Establishment (7,ysf), Expansion (21,ysf), and Mature (39,ysf). Aboveground standing plant biomass increased with time since disturbance to the Mature stage where sagebrush became dominant over herbaceous species. Phospholipid fatty acid (PLFA) analysis was used to characterize the microbial community structure. Soil microbial community productivity generally appeared to be similar to the Mature site soil (39,ysf) within 7,years of fire. Diversity of PLFAs detected in soils, at both depths, increased from a low value of 29 at the Recent site to a high of 37 at the Establishment site and then decreased again to 31 at the Mature stage site. Canonical variates analysis indicated important disparities in microbial community structure at the four sites. Greatest disparities were observed in microbial community structure between the Recent and Establishment stages but greater similarity between the Recent stage and the sagebrush dominated Mature stage. This study emphasizes both short-term and long-term changes in the belowground community and suggests that soil microbial communities are highly resilient to disturbances after prescribed fire. Copyright © 2010 John Wiley & Sons, Ltd. [source] Recovery of Greater Sage-Grouse Habitat Features in Wyoming Big Sagebrush following Prescribed FireRESTORATION ECOLOGY, Issue 3 2009Jeffrey L. Beck Abstract The ability of prescribed fire to enhance habitat features for Greater Sage-Grouse (Centrocercus urophasianus) in Wyoming big sagebrush (Artemisia tridentata wyomingensis) in western North America is poorly understood. We evaluated recovery of habitat features important to wintering, nesting, and early brood-rearing Sage-Grouse in Wyoming big sagebrush following prescribed fire. Our case study included 1 year of preburn (1989) and 10 years of postburn data collected over 14 years (1990,2003) from control and burned study areas in the Big Desert of southeastern Idaho, U.S.A. We compared recovery and rate of change for 12 features in four categories between burned and control transects and recovery in burned transects including change in variation. Our results indicate that prescribed fire induced quantifiable changes in wintering, nesting, and early brood-rearing Sage-Grouse habitat features 14 years after fire in Wyoming big sagebrush in our study area. Specifically, grass and litter required by Sage-Grouse for nest and brood concealment recovered relatively rapidly following fire; major forb cover was similar between burned and control sites, but the rate of increase for major forb cover and richness was greater in control transects, and structurally mediated habitat features required by Sage-Grouse for food and cover in winter and for nest and brood concealment in spring recovered slowly following fire. Because shrub structural features in our study did not recover in magnitude or variability to preburn levels 14 years after fire, we recommend that managers avoid burning Wyoming big sagebrush to enhance Sage-Grouse habitat, but rather implement carefully planned treatments that maintain Sagebrush. [source] Effects of Prescribed Fire and Season of Burn on Recruitment of the Invasive Exotic Plant, Potentilla recta, in a Semiarid GrasslandRESTORATION ECOLOGY, Issue 4 2003Peter Lesica Abstract Prescribed fire is often used to restore grassland systems to presettlement conditions; however, fire also has the potential to facilitate the invasion of exotic plants. Managers of wildlands and nature reserves must decide whether and how to apply prescribed burning to the best advantage in the face of this dilemma. Herbicide is also used to control exotic plants, but interactions between fire and herbicides have not been well studied. Potentilla recta is an exotic plant invading Dancing Prairie Preserve in northwest Montana. We used a complete factorial design with all combinations of spring burn, fall burn, no burn, picloram herbicide, and no herbicide to determine the effects of fire, season of burn, and their interaction with herbicide on the recruitment and population growth of P. recta over a 5-year period. Recruitment of P. recta was higher in burn plots compared with controls the first year after the fire, but this did not lead to significant population growth in subsequent years, possibly due to drier than normal conditions that occurred most years of the study. Effect of season of burn was variable among years but was higher in fall compared with spring burn plots across all years. Herbicide effectively eliminated P. recta from sample plots for 3,5 years. By the end of the study density of P. recta was greater in herbicide plots that were burned than those that were not. Results suggest that prescribed fire will enhance germination of P. recta, but this will not always lead to increased population growth. Prescribed fire may reduce the long-term efficacy of herbicide applied to control P. recta and will be most beneficial at Dancing Prairie when conducted in the spring rather than the fall. Results of prescribed fire on exotic plant invasions in semiarid environments will be difficult to predict because they are strongly dependent on stochastic climatic events. [source] Prescribed fire and conservation of a threatened mountain grassland specialist: a capture,recapture study on the Orsini's viper in the French alpsANIMAL CONSERVATION, Issue 3 2009A. Lyet Abstract Burning has traditionally been used in the southern French Alps to maintain open lands for grazing. In the context of land use abandonment, prescribed burning may be the only realistic practical tool available to oppose encroachment by woody plants in numerous mountainous landscapes. Although only recently developed as a modern tool for wildfire prevention and management of pastoral grasslands, this practice is now becoming widespread, which raises the issue of its impact on the fauna in general, and on endangered species in particular. We studied the impact of a prescribed fire on the survival and small-scale movements of one of the rarest snakes in Europe, the Orsini's viper Vipera ursinii, in order to evaluate its potential threat to population sustainability. We evaluated the body condition of snakes and the quality of their habitat, more precisely the abundance of grasshoppers as the main food resource, and the vegetation cover as shelter. About 3.6 ha of a 8.8 ha study site was burnt in autumn 2003. Snake population parameters were estimated using multi-state capture,mark,recapture methods. We demonstrate that burning reduced the survival of the vipers by more than half during the first year following the fire. Contrary to what was expected, there was no evidence of emigration from the burned to the unburned area immediately after the fire. Despite the decrease in grasshopper density and vegetation cover in the burned area, there was no evidence of mid-term mortality in snakes that could result from an increased predation rate or from the reduced body condition of snakes. As such high mortality, mainly or entirely due to the direct effect of fire, is likely to have large repercussions on population sustainability, we suggest several improvements of prescribed fire protocols to minimize their impact and strongly emphasize the need for a prescribed fire policy that takes into account specific recommendations for threatened species like Orsini's viper. The case of the Orsini's viper is very typical of conservation problems in open mountain lands, and we believe that our research will help determine the most suitable approach for long-term conservation of biodiversity in such semi-natural ecosystems. [source] Quantifying successional changes in response to forest disturbancesAPPLIED VEGETATION SCIENCE, Issue 2 2008Trent D. Penman Question: Can dissimilarity measures of individual plots be used to forecast the driving factors among various anthropogenic disturbances influencing understorey successional changes? Location: Yambulla State Forest, south-eastern Australia (37°14'S, 149°38'E). Methods: Assessments of understorey vegetation communities were taken prior to anthropogenic disturbances and at three subsequent time periods representing a period of 15 years post-disturbance. Dissimilarities were calculated from the original assessment and modelled in a Bayesian framework to examine the influence of logging, number of prescribed burns and time. Results: All sites underwent significant changes over time independently of the imposed management regimes. Logging resulted in an immediate change in vegetation assemblage which decreased in the subsequent assessments. The number of prescribed fires brought greater change in the shrub vegetation assemblages, but less change in the ground species vegetation assemblages. Conclusions: The anthropogenic disturbances did have some role in the changes of vegetation assemblages but these were minimal. The ongoing changes appear to be a natural response to the last wildfire, which passed through the study area in 1973 (13 years prior to the study). Forest management practices should consider the influence of wildfire succession when planning for the conservation of biodiversity. [source] | |||||||||||||