نتایج جستجو برای: natural forest

تعداد نتایج: 576922  

Journal: :محیط زیست طبیعی 0
بیت الله محمودی دانشجوی دکتری جنگلداری و اقتصاد جنگل دانشکدۀ منابع طبیعی دانشگاه تهران محمدرضا مروی مهاجر مروی مهاجر عضو هیئت علمی دانشکدۀ منابع طبیعی دانشگاه تهران افشین دانه کار عضو هیئت علمی دانشکدۀ منابع طبیعی دانشگاه تهران جهانگیر فقهی عضو هیئت علمی دانشکدۀ منابع طبیعی دانشگاه تهران

this study was done to investigation forest cover changes in the mazandaran province in topographic zones. for doing that in the first matched topographic zones and land-use map. after that distribution of forest cover was investigated in plain, lowland, middle land and high land. forest cover changes analyzed in a period of 132 years since the beginning of the destructive activities in the for...

Journal: :journal of agricultural science and technology 2012
n. rezaie m. h. roozitalab h. ramezanpour

all of the tea plantations in iran are concentrated in the caspian sea region on soils previously developed under deciduous natural forests. this research conducted to study the effect of land use change (from forest to tea) on selected physico-chemical and mineralogical properties of soils under humid climate and mountainous landscape in northern iran. three transects facing west to northwest ...

Journal: :international journal of advanced biological and biomedical research 2013
aboulghasem yousefi leila darvishi

increasing urbanisation and industrialisation have led to a dramatic reduction in forest area, and now only culturally protected remnants of natural forests and some new plantations remain in most areas of the north of iran. to investigate the status of the chemical and physical characteristics of soil under these remnant forests and assess the possible impacts of reforestation on soil properti...

Journal: :آمایش سرزمین 0
علی جهانی دانشجوی دکتری جنگل داری، دانشکده منابع طبیعی، دانشگاه تهران مجید مخدوم فرخنده . استاد گروه جنگل داری، دانشکده منابع طبیعی، دانشگاه تهران ، جهانگیر فقهی دانشیار گروه جنگل داری، دانشکده منابع طبیعی، دانشگاه تهران ، وحید اعتماد . استادیار گروه جنگل داری، دانشکده منابع طبیعی، دانشگاه تهران

nowadays because of various factors, including inappropriate land use, and indiscriminate exploitation of water resources, soil and vegetation, wide areas of the country were exposed to destruction of lands and desertification. therefore dealing with this situation requires a comprehensive land use program (water and land) and appropriate environment potency. the study area is patom district of...

ژورنال: علوم آب و خاک 2020

The objective of this study was to investigate the impact of land use change (forest and rangelands to agriculture) on some micromorphological indices of soil quality in part of Rakat watershed, southwest of Iran. Accordingly, intact soil samples from 0-15 and 15-30 cm depths were collected from the above-mentioned land uses, and microstructure, type and abundance of voids, redoximorphic featur...

2002
Timo Kuuluvainen

In Fennoscandia, use of the natural forest as a reference for restoration and management of forest biodiversity has been widely accepted. However, limited understanding of the structure and dynamics of the natural forest has hampered the applications of the natural variability approach. This is especially the case in areas, where the natural forests have almost totally vanished. This review was...

Aboulghasem Yousefi Leila Darvishi

Increasing urbanisation and industrialisation have led to a dramatic reduction in forest area, and now only culturally protected remnants of natural forests and some new plantations remain in most areas of the north of Iran. To investigate the status of the chemical and physical characteristics of soil under these remnant forests and assess the possible impacts of reforestation on soil properti...

Journal: :جنگل و فرآورده های چوب 0
آزاده دلجویی کارشناس ارشد مهندسی جنگل دانشکدة منابع طبیعی دانشگاه تهران، کرج، ایران احسان عبدی دانشیار گروه جنگلداری و اقتصاد جنگل دانشکدة منابع طبیعی دانشگاه تهران، کرج، ایران باریس مجنونیان استاد گروه جنگلداری و اقتصاد جنگل دانشکدة منابع طبیعی دانشگاه تهران، کرج، ایران

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...

To understand the effects of forest degradation and their conversion to farmlands, the current research was conducted with emphasis on some soil biological indexes. In this regard, two different land use including an oak natural stand and a farm next to the forest and under cultivation since 20 years ago were surveyed. Within the each land use, three sampling plots with 10×10 meter dimension we...

تارویردی‌زاده, هاجر, نقدی, رامین, پوربابایی, حسن, نیکوی, مهرداد ,

Identifying herbaceous species and their composition at forest road edges and skid trails is an urgent task to prevent changes of natural and native composition of species and invasion of exotic species. The present study aimed to evaluate the herbaceous species cover grown on the forest road surface, cut and fill slopes and skid trail surface and their comparison with inside forest in order to...

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