نتایج جستجو برای: combating desertification indices

تعداد نتایج: 91264  

Journal: :مرتع و آبخیزداری 0
الهام السادات شکوهی دانش آموخته کارشناس ارشد مدیریت مناطق بیابانی، دانشکده منابع طبیعی، دانشگاه تهران، ایران. غلامرضا زهتابیان استاد دانشکده منابع طبیعی، دانشگاه تهران، ایران. علی طویلی دانشیار دانشکده منابع طبیعی، دانشگاه تهران، ایران.

more than 80% of iran’s area has arid and semi arid climate. therefore, iran is exposed to desertification process. practical activities in controlling desertification must be based on current desertification situation and its severity. based on this theory, evaluating desertification rate indices in khezrabad region was done based on imdpa model. in this research two factors with 10 indices we...

Extended abstract 1- INTRODUCTION Destructive phenomenon of desertification is one of the serious ecological crises at the present time. In order to improve efficiency of combating desertification projects and inhibiting destruction of natural resources and our asset, it sounds considerably meaningful to reach a systematic and comprehensive method that can use different criteria and indicator...

2010
Lihua Yang Jianguo Wu

Desertification has been widely recognized as a major environmental and ecological problem facing humanity today. Combating desertification is a global challenge for sustainable development and requires collective action involving government, local communities, businesses, NGOs, and international organizations. Scholars’ role in this important endeavor and their mechanisms of participation, how...

Journal: :مرتع و آبخیزداری 0
شیما نیکو استادیار دانشکدة کویرشناسی، دانشگاه سمنان حسین آذرنیوند استاد دانشکدة منابع طبیعی، دانشگاه تهران غلامرضا زهتابیان استاد دانشکدة منابع طبیعی، دانشگاه تهران حسن احمدی استاد دانشکدة منابع طبیعی، دانشگاه تهران محمد علی زارع چاهوکی دانشیار دانشکدة منابع طبیعی، دانشگاه تهران

combating desertification which is a serious threat for the environment and human welfare requires understanding complex issues of this phenomenon using evaluation, awareness of severity of it's processes and determination of it's factors. so here, after recognizing the characteristics of the region showing existence desertification, we assess its current status with emphasis on clima...

2001
W. Tao

Land desertification is one of the most serious environmental and social-economic problems in the North China. The processes of desertification mainly have being controlled by the interaction of human activities and fragile eco-environment, that means the pattern and intension of landuse are major factors for development or reverse of desertification. Because of the increasing pressure of popul...

2011
Lixin Chen Zhiqiang Zhang Zhandong Li Jianwu Tang Peter Caldwell Wenjuan Zhang

Key Laboratory Soil and Water Conservation and Desertification Combating, Ministry of Education, College of Soil and Water Conservation, Beijing Forestry University, Beijing 100083, PR China College of Landscape Architecture and Ornamental Horticulture, Beijing Forestry University, Beijing 100083, PR China c The Ecosystems Center, Marine Biological Laboratory, Woods Hole, MA 02543, USA Raleigh ...

Journal: :journal of rangeland science 2011
g.a. heshmati

there are more than 750 counties in 13 provinces and autonomous regionsconstituting 30% of china lands which are facing serious problem of desertification. theseareas are mainly distributed in arid, semi-arid and dry sub-humid areas in the western part ofnortheast china, north central china and most of northwest china. biological methods are theultimate way for drift sand stabilization and a fu...

Journal: :desert 2008
f. taghavia h. mohammadi

climate is the most important factor which control desertification .in order to detect climate changes in desert zones, time trend analysis is applied to extreme indices in kashan station using extreme climate index software (ecis). results show significant trends in extreme indices during the past decade 1995-2004 and the pronounced warming is associated with a negative trend in cold extremes....

Journal: :Int. J. Applied Earth Observation and Geoinformation 2014
Xia Zhang Kun Shang Yi Cen Tong Shuai Yanli Sun

Coverage rates of vegetation and exposed bedrock are two key indicators of karst rocky desertification. In this study, the abundances of vegetation and exposed rock were retrieved from a hyperspectral Hyperion image using linear spectral unmixing method. The results were verified using the spectral indices of karst rocky desertification (KRDSI) and an integrated LAI spectral index: modified chl...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید