نتایج جستجو برای: forest and rangelands

تعداد نتایج: 16850589  

پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه علوم کشاورزی و منابع طبیعی گرگان - دانشکده مرتع و آبخیزداری و شیلات و محیط زیست 1391

مراتع حدود نیمی از خشکی های جهان را در بر دارند و پوشش گیاهی آن در نتیجه تأثیر متقابل محیط و موجودات زنده به وجود آمده است و به عنوان یک اکوسیستم طبیعی مدیریت می شوند. علاوه بر مراتع، راه ها در عصر حاضر نیز از اجزا مهم و زیرساخت های اصلی زندگی نوین و توسعه کشورها به شمار می روند. جاده ها ساخته دست بشر هستند و جوامع گیاهی کنار جاده تحت تأثیر ساخت و ساز قرار دارند. پوشش "رودرال" به مجموعه ای از پ...

زارعی, حیدر, شنانی هویزه, سیده مائده,

Land use change is one of the most important factors of global environmental change. So, understanding and predicting the causes, processes and consequences of land use and land cover has become a major challenge.  The Remote Sensing and Geographic Information System (GIS) technologies can be used effectively to detect and quantify of land use changes and its effects on the environment. The pur...

2010
Rhonda Skaggs

Rangelands are expansive, unimproved lands located in arid or semi–arid regions, spanning a variety of landscapes including savannahs, high and low altitude deserts, mountain meadows, and tundra. Rangelands are generally unsuitable for crop production due to aridity, topography, and extreme temperatures. Rangelands support varying mixtures of native and nonnative grasses, grass–like plants, for...

2007
William J. Elliot Peter R. Robichaud I. Sue Miller

Abstract. In both forest and rangelands, fuel reduction operations are now common practices. Mechanical thinning followed by prescribed fire is common in forests, while fire is frequently applied to rangelands. Studies at different scales (50 sq m to 389 ha) measure the erosion from fuel management. This presentation compares runoff and erosion from these studies. Plot size has the greatest inf...

Journal: :محیط زیست طبیعی 0
منصوره کارگر دانشکده منابع طبیعی دانشگاه علوم کشاورزی و منابع طبیعی ساری زینب جعفریان دانشیار دانشگاه علوم کشاورزی و منابع طبیعی ساری

natural fire inflicting irreparable damage to rangelands and forest areas is cause changes in landscape ecology. the purpose of this research is comparison of artificial neural network (ann) and line regression (lr) models to predict of forest and rangelands fires to this end, the data consist fire burned area and fire were used weather data over a period of 7 years (2006-2012(.the result indic...

2015
Ludovico Frate Alicia T. R. Acosta Marcelo Cabido Laura Hoyos Maria Laura Carranza Yohay Carmel

The context in which a forest exists strongly influences its function and sustainability. Unveiling the multi-scale nature of forest fragmentation context is crucial to understand how human activities affect the spatial patterns of forests across a range of scales. However, this issue remains almost unexplored in subtropical ecosystems. In this study, we analyzed temporal changes (1979-2010) in...

Journal: :محیط زیست طبیعی 0
سجاد عالی محمودی دانشجو کارشناسی ارشد جنگلداری، دانشکده منابع طبیعی، دانشگاه تهران جهانگیر فقهی دانشیار گروه جنگلداری و اقتصاد جنگل، دانشکده منابع طبیعی، دانشگاه تهران بهمن جباریان امیری استادیار گروه محیط زیست دانشکده منابع طبیعی دانشگاه تهران افشین دانه کار دانشیار گروه محیط زیست دانشکده منابع طبیعی دانشگاه تهران پدرام عطارد استادیار گروه جنگلداری و اقتصاد جنگل دانشکده منابع طبیعی دانشگاه تهران

fire destroys major area of forests and rangelands in the world. izhe, located in khozestan province, is one of these area that was changed by this natural phenomena. the aim of this study is to determine the most important climatic factors on forest fire and its development by regression model analysis. numbers and area of the forest fire as well as weather data for a three years period (2009-...

2012
A. Jamalian M. Shams-Ghahfarokhi A. Amani

Department of Mycology, Pasteur Institute of Iran, 13164 Tehran, Iran Department of Biology, Islamic Azad University, Science and Research Branch, Tehran, Iran Department of Mycology, Faculty of Medical Sciences, Tarbiat Modares University, 14115-331 Tehran, Iran Department of Medicinal Plants and By-Products, Research Institute of Forest and Rangelands, 13185 Tehran, Iran Medicinal Chemistry L...

Journal: :Philosophical transactions of the Royal Society of London. Series B, Biological sciences 2012
Andrew J Dougill Lindsay C Stringer Julia Leventon Mike Riddell Henri Rueff Dominick V Spracklen Edward Butt

Climate finance investments and international policy are driving new community-based projects incorporating payments for ecosystem services (PES) to simultaneously store carbon and generate livelihood benefits. Most community-based PES (CB-PES) research focuses on forest areas. Rangelands, which store globally significant quantities of carbon and support many of the world's poor, have seen litt...

حیدری, مسلم, زنگی آبادی, مریم, هنربخش, افشین, پژوهش, مهدی,

 In recent years, deferent methods for determination of optimal pattern of using water and soil resources have been applied. Due to importance of natural resources, watershed management through land use modification and correct application of land is necessary. However, single objective linear programming is not an efficient method in this matter. In this study, multi objective method of goal p...

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