نتایج جستجو برای: desertification
تعداد نتایج: 1803 فیلتر نتایج به سال:
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...
ICARDA and ICRISAT are nonproft international agricultural research centers supported by the Consultative Group on International Agricultural Research (CGIAR). They focus on sustainable agricultural development for the dryland poor. They also convene a global, multi-institutional partnership known as the Desertification, Drought, Poverty and Agriculture Consortium (DDPA) to provide research con...
This study investigated the perceived importance of scholars' participation in combating-desertification programs in northwest China and analyzed the underlying factors and mechanisms. Our results show that, while various experts, professors, and researchers have participated in combating-desertification programs, their actions were often not effective. Only those scholars who understood the lo...
Desertification is caused by the influence of the climatic, environmental changes and human activities. Its enlargement and reverse leads to not only the changes of spatial structure, scope and environment but also the development of society and economy. Chose TM remote sensing images which had two different temporal phases as data sources. Through data preprocessing and the choice of suitable ...
The process of desertification is usually modeled as a first order transition, where a change of an external parameter (e.g. precipitation) leads to a catastrophic bifurcation followed by an ecological regime shift. However, vegetation elements like shrubs and trees undergo a stochastic birth-death process with an absorbing state; such a process supports a second order continuous transition wit...
Grassland desertification by grazing and the resulting micrometeorological changes in Inner Mongolia
Overgrazing is one of the most primary causes of desertification in semi-arid zones of China. From 1992 to 1994 we conducted a grazing experiment in Naiman (lat. 42◦58′N, long. 120◦43′E, 345 m asl), Inner Mongolia, China to elucidate desertification mechanisms. Our experimental field, which was covered with some short grasses, legumes and forbs, included four plots where grazing sheep numbers d...
Desertification, one of the most severe types of land degradation in the world, is of great importance because it is occurring, to some degree, on approximately 40% of the global land area and is affecting more than 1 billion people. In this study, we used a space-for-time method to quantify the impact of five different desertification regimes (potential (PD), light (LD), moderate (MD), severe ...
Understanding how desertification takes place in different ecosystems is an important step in attempting to forecast and prevent such transitions. Dryland ecosystems often exhibit patchy vegetation, which has been shown to be an important factor on the possible regime shifts that occur in arid regions in several model studies. In particular, both gradual shifts that occur by front propagation, ...
The monitoring of desertification processes, and particularly the development of "early-warning" systems, is an increasingly important development in the management of drylands. It has been shown that the patch size distribution of dryland vegetation can be described using power laws and that deviations from such patterns may be used as an early-warning signal for the onset of desertification. ...
Germany has made the United Nations Convention to Combat Desertification (UNCCD) since its creation an instrument of choice for its policy to combat desertification and drought and for sustainable management of land. More then ten years after the Convention has entered into force in 1996, Germany continues to view it as a key reference point and strategic instrument of its development cooperation.
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید