نتایج جستجو برای: forest clearing
تعداد نتایج: 113265 فیلتر نتایج به سال:
Developing countries are increasingly decentralizing forest governance by granting indigenous groups and other local communities formal legal title to land. However, the effects of titling on forest cover are unclear. Rigorous analyses of titling campaigns are rare, and related theoretical and empirical research suggests that they could either stem or spur forest damage. We analyze such a campa...
The importance of the Northern Guam aquifer as a source of drinking water for the tropical Pacific island of Guam has stimulated public interest in the impact of forest clearing and conversion to agriculture on the region’s environment. The objectives of this study were to determine the effects of land clearing, tillage, and fertilization of tropical secondary forest on soil organic and organic...
Individual identification of the relatively cryptic forest elephant (Loxodonta cyclotis) at forest clearings currently provides the highest quality monitoring data on this ecologically important but increasingly threatened species. Here we present baseline data from the first 20 years of an individually based study of this species, conducted at the Dzanga Clearing, Central African Republic. A t...
Clear-cutting of forests affects the nitrogen cycle and the nitrogen isotopic composition of bioavailable ammonium and nitrate in the soil. Here, we have used nitrogen isotopic variations of tree-rings in red oak (Quercus rubra) and white oak (Quercus alba) as indicators of changes in the nitrogen cycle on a local scale. The delta15N values of late-wood from trees at two remnant forest stands i...
Early-successional vegetation is often a major factor that limits recovery of tropical forest in abandoned pastures by outcompeting seedlings of forest trees. The goal of this study was to compare the effects of aboveand below-ground competition of pasture grasses and shrubs on the growth of tree seedlings in abandoned tropical pasture in Costa Rica. Seedlings of Calophyllum brasiliense were pl...
To understand the leaf-level responses of successional tree species to forest gap formation and nitrogen deposition, we performed canopy clearing and nitrogen-amendment treatments in larch plantations and investigated the changes in the light-use characteristics and the leaf structure of the invading deciduous broad-leaved tree seedlings. We hypothesized that the responses of the tree seedlings...
This paper uses household level data to examine the ecological and political factors and household characteristics associated with small farmer land use change and forest clearing between 1993 and 1998. The research site is a settlement frontier within a protected area in northern Guatemala. The great expanse of accessible, open land of the Sierra de Lacandón National Park (SLNP) has been a mag...
forest roads are directions in natural habitats that used to transport wood products, secondary forest products and recreation. constructing forest roads causes trees clearing with specified width thus lead to direct or indirect changes in forest ecosystems and forest environment. this study aims to assess the changes of diversity and richness indices in main and secondary forest roads in a par...
Tropical forest habitat continues to decline globally, with serious negative consequences for environmental sustainability. The small mountain country of Nepal provides an excellent context in which to examine trajectories of forest-cover change. Despite having experienced large-scale forest clearing in the past, significant reforestation has taken place in recent years. The range of biophysica...
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