نتایج جستجو برای: 26 forest cover types
تعداد نتایج: 833058 فیلتر نتایج به سال:
The concept of naturalness was developed to assess to what degree landscapes represent a natural state. Protected areas are often regarded as the remnants of untouched landscapes although many landscapes commonly perceived as pristine have a long history of human impact. Here, we introduced a historical perspective into the concept of naturalness and the analysis of the effectiveness of protect...
Accurate estimates of forest cover and forest fragmentation are critical for developing countries such as Costa Rica, which holds four to five percent of the world’s plant and bird species. We estimated forest cover for Costa Rica using Landsat 5 Thematic Mapper satellite scenes acquired between 1986 and 1991. In 1991, 29 percent (ca 14,000 km2) of the land cover of Costa Rica was closed forest...
In this paper novel algorithms developed to automatically segment forest cover types are presented. The digital image analysis followed is mainly based on mathematical morphology operators and exploits the textural features in high spatial resolution images. These input images consist of true colour digital orthophotos and the studied forest covers consist of the main occurrences in Portugal: o...
physiological factors have effects on most forest parameters such as forest classification so that understanding knowledge about this subject is important to manage forests. the forests of sorkhake-sanjabi village with area of 1645 ha located in eslam abad city, kermanshah province, iran were selected. 23 sample plots with rectangular shape (40m*50m) were selected and the species, origin of spe...
Insular Southeast Asia is a hotspot of humid tropical forest cover loss. A sample-based monitoring approach quantifying forest cover loss from Landsat imagery was implemented to estimate gross forest cover loss for two eras, 1990–2000 and 2000–2005. For each time interval, a probability sample of 18.5 km × 18.5 km blocks was selected, and pairs of Landsat images acquired per sample block were i...
Basin forest cover is understood to influence stream baseflow in a variety of ways, most significantly via increased soil infiltration and increased evapotranspiration (ET). Extensive forestry experimentation has consistently demonstrated a negative relationship between forest cover and baseflow, attributed to ET losses associated with greater forest cover. However, it is unclear whether this r...
forest fragmentation results in a loss of forest interior and an increase in edge habitat. we studied how understorey bird community composition and habitat variables changed along an edge-to-interior gradient in a 1248-ha lowland rainforest patch in peninsular malaysia. birds and environmental variables such as vegetation structure and litter depth were detected within a 25-m radius of each of...
Micro-scale changes in earthworm communities and ground cover types were studied along five transect lines in an unmanaged beech forest (Fontainebleau forest, France). Spatial patterns were interpreted to the light of interactions between earthworm species and forest architecture, ground vegetation and quantity as well as quality of litter. The anecic Lumbricus terrestris was associated with pa...
In East Africa, human population growth and demands for natural resources cause forest loss contributing to increased carbon emissions and reduced biodiversity. Protected Areas (PAs) are intended to conserve habitats and species. Variability in PA effectiveness and 'leakage' (here defined as displacement of deforestation) may lead to different trends in forest loss within, and adjacent to, exis...
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