نتایج جستجو برای: gorazbon
تعداد نتایج: 18 فیلتر نتایج به سال:
assessment and management of the environmental impacts of forest harvesting operations have become increasingly critical factors in practicing commercial forestry. this study investigated soil disturbance from a forest logging system operation on an 8-hectare mixed broadleaved stand in compartment no. 309 in gorazbon district in kheyrud educational and research forest. the objective of this stu...
forest harvesting operations for extracting of forest products in these trails, causing extensive damage in a wide range of soil and its productivity every year, therefore it is necessary to research about degradation of soil properties should be down. the aim of this study was investigate changes in the skid trails soil physical characteristics due to wheeled cable skidder traffic by measuring...
hyrcanian forests are the most valuable forests in the north of iran and industrial harvesting occurs only in this area. it is a productive region near the southern coast of caspian sea. in these forests mixed beech stands mostly shown uneven-aged structure that is managed under selection system. in order to determine the priority of uneven aged method not only from an ecological view, but also...
elm (ulmus glabra hudson) is one of the most valuable species which distribute all over the caspian forests. nowadays, elm is considered an endangered species due to intensive human activities and outbreak of dutch elm disease over the last few decades. to suitable management of elm, there is need to have indices which describe; current structure and its changes across the time. this study besi...
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...
quantifying spatial structure is one of the most important components, describing natural ecosystems and their biodiversity. in this study, a set of indices and functions related to spatial structure using 102 established plots with an area of 1000 m2 were presented. to achieve spatial structure of carpinus-fagus type, a set of indices (clark & evans, uniform angle, shannon-wiener, mingling and...
beech forests in midland areas of hyrcanian forests of iran are the most important forests having the highest degree of naturalness. these forests are the valuable source of wood production and other forest products. one of the most important characteristics of plant communities is the spatial pattern of trees. ecological process in forest ecosystems are directly influenced by the spatial patte...
علوم و تکنولوژی محیط زیست، دورهنوزدهم، شماره چهار، زمستان 96 بررسی ساختار تودههای انارشیطان (Tecomellaundulata R.) در استان بوشهر زهرا ذولفقاری[1] مصطفی مرادی [2] * [email protected] رضا بصیری [3] اکبر قاسمی[4] تاریخ دریافت:21/9/94 تاریخ پذیرش:6/11/94 چکیده زمینه و هدف: ساختار از عوامل مهم زیست محیطی است که میتواند ویژگیهای منحصر به فردی را در جنگل ایجاد نماید...
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