نتایج جستجو برای: forest species changing
تعداد نتایج: 771031 فیلتر نتایج به سال:
Extended abstract 1- Introduction Changing the forests and pasture landuses to agricultural lands is one of the major global concerns about environmental degradation and climate change. As a result of the rangeland and forest changes into agricultural land and also tillage operations, about 430 million hectares, representing 30% of the world's total plowed land, are annually eroded and leavin...
To implement correct management of forest ecosystems, enough information in relation to the structures of tree species is necessary. In this study, the structures of trees species in Fagus, Fagus-Carpinus, Carpinus-Fagus and Carpinus-Quercus types were investigated and compared in Hyrcanian forest. The data used in this study was collected from 239 plots with an area of 1000 m2 in Gorazbon dist...
Climate change threatens natural landscapes through shifting distribution and abundance of species and attendant change in the structure and function of ecosystems. However, it remains unclear how climate-mediated variation in species' environmental niche space may lead to large-scale fragmentation of species distributions, altered meta-population dynamics and gene flow, and disrupted ecosystem...
Silvicultural operation need to notice the plant species diversity in forest. To this study Gomarlang district in marivan region, northern zagros forest was selected. Selected 100 ha area because have similar physiography condition (north aspect and 1650 to 1800 m s.a.l. In study area 100 micro plots of 5m by 5 m (25 m2) including the species and the numbers of this species randomize...
The aim of this research was to investigate the diversity of tree and shrub species in forestry plan in a watershed and in almost the same ecological conditions but different in forest management plan in the part of Golestan province forest. To this end, the 6675 hectares of the watershed number of 85 in 5 different plans in series one (30-year forestry plan with University Scientific Managemen...
this study was performed in order to consider the effect of management plans on forest, through comparison between qualitative and quantitative characteristics of managed and unmanaged forests. compartment no. 149 from shourab district (52.8 ha) and compartment no. 218 from jamand district (68.7 ha) were selected as managed and unmanaged forests, respectively and were inventoried using a system...
although host species generally face increased risk of brood parasitism in fragmented temperate landscapes and forest edge, little information exists to assess such risks in tropical birds. we studied how cuculidae species populations, host species population, and micro-environmental variables changed along an edge-to-interior gradient in peninsular malaysia. bird observations and environmental...
As the climate warms, boreal tree species are expected to be gradually replaced by temperate species within the southern boreal forest. Warming will be accompanied by changes in above- and below-ground consumers: large moose (Alces alces) replaced by smaller deer (Odocoileus virginianus) above-ground, and small detritivores replaced by larger exotic earthworms below-ground. These shifts may ind...
Silvicultural operation need to notice the plant species diversity in forest. To this study Gomarlang district in marivan region, northern zagros forest was selected. Selected 100 ha area because have similar physiography condition (north aspect and 1650 to 1800 m s.a.l. In study area 100 micro plots of 5m by 5 m (25 m2) including the species and the numbers of this species randomize...
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