نتایج جستجو برای: forest fragmentation
تعداد نتایج: 139402 فیلتر نتایج به سال:
We used a comparative mensurative landscape-level experiment to quantify the relative importance of mature forest area and fragmentation and differences among watersheds in influencing avian community diversity in the Oregon Coast Range, USA. Our study design included three large hydrological basins, two levels of fragmentation, and six levels of mature forest area. We recorded 82 species of bi...
Plantinga, Andrew J.; Alig, Ralph J.; Eichman, Henry; Lewis, David J. 2007. Linking land-use projections and forest fragmentation analysis. Res. Pap. PNWRP-570. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Station. 41 p. An econometric model of private land-use decisions is used to project land use to 2030 for each county in the continental United States. On a...
Because human land uses tend to expand over time, forests that share a high proportion of their borders with anthropogenic uses are at higher risk of further degradation than forests that share a high proportion of their borders with non-forest, natural land cover (e.g., wetland). Using 1-km advanced very high resolution radiometer (AVHRR) satellite-based land cover, we present a method to sepa...
Impact of changes in land cover and land use on hydrological service of tropical watersheds is one of the focal research tropics in both hydrology and Land Cover Land Use Changes (LCLUC). Land fragmentation is an important feature of LCLUC, however, its impact on hydrological service of tropical watershed is unclear despite a few theoretical frameworks. In this paper, we described a simulation ...
Habitat degradation alters the dynamics and composition of anuran assemblages in tropical forests. The effects of forest fragmentation on the composition of anuran assemblages are so far poorly known. We studied the joint influence of forest fragmentation and degradation on leaf-litter frogs. We specifically asked whether the processes structuring leaf-litter anuran assemblages in fragmented fo...
Conservation policies influence both the amount of habitat loss and patterns of habitat fragmentation. This paper develops a “microlandscapes” approach that combines fragmentation measures with quasi-experimental evaluation methods in order to assess the effects of policy on habitat fragmentation. As an application, the paper estimates whether and to what extent wildlife sanctuaries and nationa...
Tree species are key organisms of forest ecosystems, due their size and extended life, providing the environmental setting for many other living organisms. The levels of genetic diversity and the effective population sizes are essential issues for the maintenance and survival of tree species populations, because they direct adaptation to the current environment and future environmental changes....
Tropical forest understory birds are highly sensitive to habitat fragmentation. Recent results from a monumental Amazonian fragmentation experiment show that habitat needs of these specialized birds make mobility a liability, leading to their extinctions from forest fragments.
The question of incorporating road maps into U.S. national assessments of forest fragmentation has been a contentious issue, but there has not been a comparative national analysis to inform the debate. Using data and indices from previous national assessments, we compared fragmentation as calculated from high-resolution land-cover maps alone (Method 1) and after superimposing detailed road maps...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید