نتایج جستجو برای: forest trees

تعداد نتایج: 184211  

توانکار, فرزام, نیکوی, مهرداد,

Rotten and dead trees are the main component of forest ecosystems and play an important role in maintaining forest biodiversity. In this research frequency and characteristics of large diameter trees (normal, rotten, and dead trees) with diameter at breast height greater than 60 cm were studied in two compartments (selective logged and protected) in Asalem-Nav forest. Random systematic sampling...

رضایی, حمیدرضا, وارسته‌مرادی, حسین, کریمی, سرور,

  Investigation of the ecological characteristics of wildlife species and determination of habitat suitability for them is one of the main pillars for wildlife management and protection. In this study, the winter and spring habitat suitability of black woodpecker (Dryocopusmartius) was studied in ShastKalateh forest. Habitat characteristics, including forest vegetationtype, structural character...

Dead trees protection, has a key role in structural and biogeochemical processes in forest ecosystems. Some aspects of dead tree dynamics have been carefully studied, but the kind and decay degree of dead trees and forest soil properties have not received enough attention. The aim of this research was to study the effect of a kind and decay degree of dead trees on soil mineral properties in the...

Journal: :جنگل و فرآورده های چوب 0
فریده امیدوار حسینی دانشجوی کارشناسی ارشد رشتۀ جنگلداری، دانشگاه آزاد اسلامی، واحد علوم و تحقیقات تهران، تهران، ایران رضا اخوان استادیار پژوهش، مؤسسۀ تحقیقات جنگل ها و مراتع کشور، تهران، ایران هادی کیادلیری استادیار گروه جنگلداری، دانشگاه آزاد اسلامی، واحد علوم و تحقیقات، تهران، ایران اسداله متاجی دانشیار گروه جنگلداری، دانشگاه آزاد اسلامی، واحد علوم و تحقیقات، تهران، ایران

one of the most visible aspects of a forest stand structure is the spatial patterns of trees. competition affects on forest structure and its understanding is important, when the purpose of forest management is to imitate the dynamic of natural ecosystems. for this purpose, an unmanaged intact forest was selected with 26 hectares area. all chestnut leaf oak (quercus castaneifolia) trees with a ...

.  Introduction Old trees are important and key elements of forest sites and are of great value in terms of forest management, reforestation, silviculture and ecology. Although old trees constitute a small percentage of forest trees, they account for a large share of forest carbon reserve and play a vital role in carbon storage. Understanding the how geographical and site distribution of thes...

Journal: :پژوهش های علوم و فناوری چوب و جنگل 0

the evaluation of the edge effects of forest roads on ecosystem is very useful to understand changes from forest road. with this regard, in this research the effect of main forest road construction on regeneration and biodiversity of established trees in edge of forest road was investigated at 35 m distance into forest area. an existing 10 years old road segment, with same physiographic propert...

Trees are the most important biological elements of forest ecosystems. The variability of the tree species composition inhabiting in the Oriental beech forest, not only forms different forest types but also has a remarkable impact on the species diversity of forest floor plants, due to the existence of trees in the overstory layer. In this research, forest types of an an Oriental beech were ide...

Tree marking can cause changes in forest. This study aimed to assess tree marking operation and to predict its effect on stand structure of Persian ironwood-hornbeam stands at Bahramnia forestry plan, north of Iran. Therefore 98 trees that were marked in compartment 9 of the mentioned forest in 2017 based on selection system and according to the recent laws of Forests, Range and Watershed Manag...

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...

Journal: :جنگل و فرآورده های چوب 0
مرتضی مریدی دانشجوی کارشناسی ارشد جنگل‏ شناسی و اکولوژی جنگل دانشکدة منابع طبیعی دانشگاه تهران، کرج، ایران وحید اعتماد استادیار گروه جنگل داری و اقتصاد جنگل دانشکدة منابع طبیعی دانشگاه تهران، کرج، ایران کیومرث سفیدی استادیار دانشکدة فناوری کشاورزی و منابع طبیعی دانشگاه محقق اردبیلی، اردبیل، ایران منوچهر نمیرانیان استاد گروه جنگل داری و اقتصاد جنگل دانشکدة منابع طبیعی دانشگاه تهران، کرج، ایران سید محمد معین صادقی دانشجوی کارشناسی ارشد جنگل‏ شناسی و اکولوژی جنگل دانشکدة منابع طبیعی دانشگاه تهران، کرج، ایران

knowledge of the stand condition and the gradual replacement of tree species in different development stages and phases provide appropriate information related to the close to nature treatments. stem exclusion phase is one of the important development phases in the forest stands development. the aim of study was to analyze the characteristics of dead trees in the stem exclusion phase in the les...

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