نتایج جستجو برای: extent of area by forest type relative to total forest area
تعداد نتایج: 22688644 فیلتر نتایج به سال:
In the Shafaroud forest, logging operation is generally performed by using selective cutting methods. Chainsaw and cable skidder are two main forest machines for harvesting of this forest. However, forest harvesting operations result in serious residual stand damage during felling, winching and skidding operations in this forest. Residual stand damage resulting from selective cutting was asses...
Land cover has rapidly changed due to the relatively high population density, high rate of seasonal and permanent migrants, favorable conditions of natural and cultural, frequency of industrial units, coastal border and harbour and great rate of construction in the mazandaran province in recent years. Land cover changes are led to fragmentation, perforation, dissection, shirinkage, attrition an...
natural fire inflicting irreparable damage to rangelands and forest areas is cause changes in landscape ecology. the purpose of this research is comparison of artificial neural network (ann) and line regression (lr) models to predict of forest and rangelands fires to this end, the data consist fire burned area and fire were used weather data over a period of 7 years (2006-2012(.the result indic...
Singapore, a tropical island of only 716 km2, has substantial land under forest. But rapid urbanisation coupled with the scarcity of land has also resulted in exten‐ sive land clearance. Though highly urbanised, Singapore has managed to retain 4.5% of the land area under nature conservation, and 2.9% under closed forest. Out of four protected areas, two of these, the Central Water Catchment For...
the following null hypothesis was proposed: h : there is no significant difference between the use of semantically or communicatively translates scientific texts. to test the null hypothesis, a number of procedures were taken first, two passages were selected form soyrcebooks of food and nutrition industry and gardening deciplines. each, in turn, was following by a number of comprehension quest...
hedging is a multi-purpose rhetorical strategy which is usually used in scientific arguments to secure ratification of claims, reduce the risk of negation, avoid conflict, manage disagreement and leave room for the audience to assess presented information. hedges are frequently used in research articles to mitigate the findings of research endeavors. the present research aims to investigate the...
Fire, as a natural ecological disturbance factor in forest, this study located in the Marivan region, Northern Zagros forest, and western Iranian state of Kurdistan. In each burned and unburned area 30 circle sample plot (1000 m2) were collected by randomized–systematic method in the 100×200 m net (in total 60 plots). In every sample plot the kind of species, number of tree, the heig...
Accurate, current, and cost-effective fire fuel data are required by management and fire science communities for use in reducing wildland fire hazards over large areas. In this paper we present results of applying decision-tree techniques to mapping vegetation parameters (such as vegetation types and canopy structure classification) required for fire fuel characterization. Specifically, we pres...
Forest roads are the most important elements of forestry projects, the management, supervision, care, and only access way to the forest for mechanized harvesting and using other services of forests. The aim of this study was to compare the current annual increment of basal area in different distances from the road in northern forests of Iran. For this purpose, 50 plots were established in 5 dis...
The aim of this study was to investigate vegetation composition in broadleaved and conifers plantations in 220 ha of Loblloly pine (Pinus taeda), alder (Alnus glutinosa( and poplar (Popolus deltoides) hardwood plantations and its comparison with natural forests in Bibiyanlu protected forest park, Astara. A total of 60 sampling plots of 1000 m2 were taken using randomly-systematic method with1...
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