نتایج جستجو برای: damaged and destroyed) and trees bole wounds (location

تعداد نتایج: 16859155  

Journal: :محیط شناسی 0
فرزام توانکار دانشگاه آزاد اسلامی، واحد خلخال، استادیار علوم جنگل امیر اسلام بنیاد دانشکدة منابع طبیعی دانشگاه گیلان، صومعه سرا ، دانشیار علوم جنگل باریس مجنونیان دانشکدة منابع طبیعی دانشگاه تهران، استاد مهندسی جنگل

selection cutting using skidding system often causes physical damage to residual stand through felling and skidding resulting decline of bole quality and tree value. this research evaluated logging damage using skidding system on residual trees and stand regeneration in uneven aged hardwood forest of asalem, were selection cutting was practiced. in this regard, systematic sampling method was us...

Journal: :جنگل و فرآورده های چوب 0
امیر اسلام بنیاد دانشیار سنجش از دور و بیومتری جنگل دانشکدة منابع طبیعی دانشگاه گیلان، صومعه سرا، ایران فرزام توانکار استادیار مهندسی جنگل واحد خلخال دانشگاه آزاد اسلامی، خلخال، ایران

in this research resistance of six tree species to logging damages (bole wound) after 12 years were studied in district 1 of asalem nav forests. the data of extent and severity of damages on residual trees were collected immediately after logging operation from systematic sampling with circular 0.1 ha plots in the year of 2000. the damaged trees and wounds condition were reexamined in the year ...

پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه شهید باهنر کرمان - دانشکده ادبیات و علوم انسانی 1389

abstract this research has been carried out with the purpose of investigating the conditions and related elements of the employment of the educational sciences graduates of hamedan province universities in 1382-1387 academic years. it has been a descriptive research of a correlation kind, and the population number has been 1180 grduates of payam- e noor universites in asad – abaad, kaboudaraha...

پایان نامه :دانشگاه تربیت معلم - تهران - دانشکده ادبیات و علوم انسانی 1391

abstract global financial crisis has created too many problems in relations among governments. among these problems, the issue of global monetary management, more than every time in the past four decades, has been moved in the center of international economic attentions. a problem which is specially known with the monetary hostility between united states and public republic of china. where ar...

پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه سیستان و بلوچستان - دانشکده مهندسی عمران 1391

one of the most commonly used techniques to reduce the corrosion rate of rebar in concrete is addition substances named corrosion inhibitors into the concrete. corrosion inhibitor is chemical compounds that were added to concrete to prevent corrosion of steel in concrete. sodium nitrate is a type of anodic inhibitors that this study investigatesthe effect of this inhibitor on the properties of ...

پایان نامه :وزارت علوم، تحقیقات و فناوری - پژوهشگاه مواد و انرژی - پژوهشکده سرامیک 1392

thermal barrier coatings (tbcs) are used to provide thermal insulation to the hot section components of gas turbines in order to enhance the operating temperature and turbine efficiency. hot corrosion and thermal shocks are the main destructive factors in tbcs which comes as a result of oxygen and molten salt diffusion into the coating. in this thesis atmospheric plasma spraying was used to dep...

In recent years dieback and decline of oak trees in Zagros forests as an important environmental issue was raised and in many areas has been destroyed trees. In this regard, in order to provide operational strategy to manage this problem and use of the resprouting ability of oak trees. Four hectares of Brant`s oak (Quercus brantii Lindl.) stands in Dasht-e Barm basin of Kazeroon, Fars province,...

ژورنال: علوم آب و خاک 2009
اسلام بنیاد, امیر, توانکار, فرزام, مجنونیان, باریس,

Forest future depends on forest stands regeneration. Soil is one of the principal capitals in the forest area. It is important to minimize damages to the forest ecosystem during logging operation. In forestry and forest management, it is significant to know the effect of forest logging damages on regeneration, sapling and soil compaction. This study was carried out in Asalem Beech forest area, ...

پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه سیستان و بلوچستان - دانشکده علوم پایه 1391

abstract the balvard metamorphic assemblage (bma) crops out at the northeastern margin of the southeastern part of the sanandaj-sirjan zone (ssz) in contacting to the dehshir-baft ophiolitic mélange. this location prepared a special situation to resolve some of the complicated tectonic problems of this part of iran. petrology, micro-tectonics and satellite image investigation were carried out ...

2006
James H. Roberds Brian L. Strom

Repeatability was estimated for constitutive oleoresin yield measurements in 10 stands of three species of pines native to southeastern United States. Trees of these species that discharge large quantities of oleoresin upon wounding are considered to be most resistant to attack by southern pine beetle (Dendroctonus frontalis Zimmermann). Oleoresin yield is usually measured from one or more smal...

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