نتایج جستجو برای: forest and pastures
تعداد نتایج: 16850860 فیلتر نتایج به سال:
We evaluated changes of different soil nitrogen forms (total N, available ammonium and nitrate, total N in microbial biomass, and soil N mineralization) after conversion of semideciduous dry tropical forest in 5- and 18-year-old pastures (YP and OP, resp.) in the western Llanos of Venezuela. This evaluation was made at early rainy season, at end rainy season, and during dry season. With few exc...
On 14 September 1988 Hurricane Gilbert, the strongest tropical storm ever recorded in the Western Hemisphere, passed through an area of tropical forest in Quintana Roo, Mexico, where I had been studying winter bird populations since 1984. The hurricane defoliated the forest, and created a nearly impenetrable tangle of fallen branches and vines at ground level. Point counts and mist-netting cond...
Photochemical and microbial degradation of external inputs of dissolved organic matter (DOM) from both natural (forests) and anthropogenic (swine and equine pastures) non-point sources to rivers were examined through field and laboratory microcosm experiments. Little or no photochemical degradation of DOM to inorganic N or P occurred in either the agricultural or forest runoff. The dissolved or...
Hawthorn (Crataegus monogyna) is a naturalised tree that is classified as a noxious plant in several counties in the eastern South Island. It is locally abundant in lowland forest remnants, and with the indigenous spiny shrub matagouri (Discaria toumatou), on grazing land in Canterbury. Two scrub sites near Porters Pass, where the original hawthorn trees still existed, and a forest site near Ko...
Many studies have evaluated the effect of forest fragmentation on dung beetle assemblage structure. However, few have analyzed how forest fragmentation affects the processes carried out by these insects in tropical forests where their food sources consist mainly of dung produced by native herbivore mammals. With the conversion of forests to pastures, cattle dung has become an exotic alternative...
Extended abstract 1- Introduction The forests of the Zagros vegetation area cover about six million hectares (40%) of Iran's forest area, which is dominated by oak species. These forests are exposed to a number of threats, including land use change, deforestation, over grazing, deliberate and unintentional fires, pest and disease attacks, and climate change. Although accurate and timely...
Restoration of grasslands dominated by tall fescue (Schedonorus phoenix [Scop.] Holub) to native tallgrass prairie usually requires burning, herbicides, or reseeding. We tested seasonal grazing by livestock in winter, combined with cessation of fertilization, as a restoration tool for modifying the competitive dynamics among herbaceous plants to restore tallgrass prairie communities in southeas...
pastures play an important role in protecting environment and ecosystems. unfortunately more than 40 percent of pasturess in the world have been destroyed and 20 percent of destroyed pastures are located in developing countries. application of solar energy could significantly contribute to preserving the pastures. the main purpose of this study was to examine the role of solar energy in protect...
We have witnessed a drastic increase in global fires recent years that are strongly linked to climate change. On the other hand, prescribed applied agricultural practice; however, their effectiveness is controversial. It important study effects of both types – wild and predict impact on biota. In this study, four different locations Central Norther Bulgaria recovered after fire were studied con...
Aims: Land-use change due to human activities is one of the important issues in regional and development planning. The aim of this study was to detect land-use changes using Landsat TM, ETM+, IRS and ASTER satellite imagery. Methodology: In this quasi-experimental study, land-use changes in the Haraz watershed over a 23-year period were evaluated. For this study, images of 1992 TM, ETM + 2002, ...
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