نتایج جستجو برای: and forest

تعداد نتایج: 16850233  

Esmaeil Khosropour Maziar Haidari Vahid Etemad

Regeneration and forest durability guarantee is one of the most important aspects of forest sustainability and it should be placed in forest plans priority. To compare regeneration in the two grazed and non-grazed forest, Baghe-shady forest located in Khatam city (it has the preservative regions that they are 20 years old), Yazd province, Central of Iran was selected. For this purpose, 60 sampl...

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...

ژورنال: علوم آب و خاک 2006
علی اصغر درویش صفت , , امید رفیعیان, , منوچهر نمیرانیان, ,

The aim of this study was to detect change of the forest area in the north of Iran between 1994 and 2001. The study area was covered by a 1:25000 topographic map (about 15000 ha) in Babol forests. The forest map of 1994 was extracted from 1:25000 topographic digital map. Landsat 7 ETM+ image dated July 30, 2001 was analyzed to produce the forest map for the end of the period. Since the evaluati...

Estimating the amount of variation due to spatial dependence at different scales provides a basis for designing effective experiments. Accurate knowledge of spatial structures is needed to inform silvicultural guidelines and management decisions for long term sustainability of forests. Furthermore, geostatistics is a useful tool to describe and draw map the spatial variability and estimation o...

اسلامی, علیرضا, جعفری, فرهنگ, حسنی, مجید,

In the high forests which managing with close-to-nature silvicultural method, the future of forests depends on the stable establishment of saplings planted in the gaps; hence, the current study was done by selection sampling method with the aim of qualitative and quantitative investigation of natural regeneration based on the gap area in two different beech (Fagus orientalis Lipsky) forests: pu...

Journal: :جنگل و فرآورده های چوب 0
اصغر فلاح دانشیار گروه علوم جنگل، دانشکدة منابع طبیعی، دانشگاه علوم کشاورزی و منابع طبیعی ساری، ساری، ایران سیاوش کلبی دانشجوی دکتری گروه علوم جنگل، دانشکدة منابع طبیعی، دانشگاه علوم کشاورزی و منابع طبیعی ساری، ساری، ایران شعبان شتایی دانشیار گروه جنگل‏داری، دانشکدة منابع طبیعی، دانشگاه علوم کشاورزی و منابع طبیعی گرگان، گرگان، ایران امید کرمی دانشجوی دکتری گروه علوم جنگل، دانشکدة منابع طبیعی، دانشگاه علوم کشاورزی و منابع طبیعی ساری، ساری، ایران

recognition equal units and segregation them and upshot planning per units most basic method for management forest units. aim this study presentation and comparison classification and regression tree (cart) and random forest (rf) algorithm for forest type mapping using aster satellite data in district one didactic and research forest's darabkola. in start using inventory network 500* 350 m...

Journal: :iranian journal of allergy, asthma and immunology 0
sung chul seo environmental health center for asthma, korea university anam hospital, seoul, korea. su jin park department of forest welfare, korea forest research institute, seoul, korea. chan-woo park department of forest welfare, korea forest research institute, seoul, korea. won suck yoon allergy and immunology center, korea university, seoul, korea. ji tae choung environmental health center for asthma, korea university anam hospital, and department of pediatrics, korea university anam hospital, seoul, korea. young yoo environmental health center for asthma, korea university anam hospital, seoul, korea and allergy and immunology center, korea university, seoul, korea and department of pediatrics, college of medicine, korea university, seoul, korea

asthma and atopic dermatitis are common allergic diseases, and their prevalence has increased in urban children. recently, it is becoming understood that forest environment has favorable health effects in patients with chronic diseases. to investigate favorable clinical and immunologic effects of forest, we examined changes in clinical symptoms, indirect airway inflammatory marker, and serum ch...

Journal: :جنگل و فرآورده های چوب 0
جواد اسحاقی راد دانشیار گروه جنگل داری دانشکدۀ منابع طبیعی دانشگاه ارومیه، ارومیه، ایران آمنه خانعلیزاده دانشجوی دکتری جنگل داری، دانشکدۀ منابع طبیعی دانشگاه ارومیه، ارومیه، ایران

this study was performed in order to investigate the changes in vegetation and soil properties in compartment no.317 (managed forest) and no.318 (control forest) of jamand district of golband forest in mazandaran (noshahr). for this purpose, random-systematic sampling method with regular grid of 100×200 m was used to locate samples. the plot size was 400 m2 considering to tree and shrub species...

Journal: :جنگل و فرآورده های چوب 0
رویا عابدی دانش آموخته دکترای جنگلداری/دانشکده منابع طبیعی، دانشگاه گیلان سید امیراسلام بنیاد استاد/دانشکده منابع طبیعی دانشگاه گیلان اسدالله شاه بهرامی دانشیار/دانشگاه گیلان

proper forest management needs quantitative and precise estimates of forest stands characteristics. remotely sensed imageries, due to accurate and broad spatial information, has become a cost-effective tool in forest management. classification of forest attributes and generation of thematic maps are among the common applications of remote sensing. the objective of this study was to optimize the...

Journal: :desert 2006
a. kelarestaghi h. ahmadi m. jafari

land use change may influence many natural phenomena and ecological processes, including runoff, soil erosion, sedimentation and soil conditions. decreasing of forest area in the north of iran is one of the critical problems in recent years. the aims of this study are to detect land use changes between 1967 to 2002 using satellite images of land sat 7 etm+ (2002), aerial photos and digital topo...

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