مقاله Desert Transformation or D‌esertification Control?

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بخشی از متن مقاله Desert Transformation or D‌esertification Control? :

سال انتشار : ۲۰۱۱

تعداد صفحات :۸

The UNCCD has been ratified by over 190 countries. It is the attempt by nations, both rich and poor to control the scourge of desertification. The definition of which is “land degradation in arid, semiarid, and dry subhumid areas resulting from various factors, including climatic variations and human activities. It is now widely accepted that desertification is not the relentless advance of desert but rather the development of land degradation in discrete sites that can coalesce and spread (Squires and Sidahmed 1998). China, a signatory to the UNCCD, has a large area of desert and an alarming rate of desertification of all types wind and water erosion, and soil salinization (Luo and Zhang 2006). In China for example, in provinces such as Ningxia, Inner Mongolia and Gansu the local officials report that the rate of expansion of desertified lands is proceeding at double the rate of control measures. Clearly, this is unsatisfactory and better ways must be found to reverse the trend. National efforts to combat desertification employ a range of measures, some physical and others relate to socio-economic and policy change (Lu et al. 2005). Other countries that are UNCCD signatories face similar problems. Sandy desertification[1] (sandification) is of great concern in China (Wang 2000). Iran and countries of the Gulf Persian region (Al Faraji 2002). Until recently the area of sandification in China was growing at a rapid rate, despite efforts to combat it (Fig 1). It is estimated that the rate of rangeland degradation in semi arid and dry sub-humid areas is 90-97%, and the annual rate of rangeland degradation is accelerating. But, in China as a whole, from 2004 onwards the rate of expansion of land affected by sandification has declined and in some areas it has been reversed (Luo and Zhang 2006). Other forms of desertification, especially in the marginal cropping lands in the interface zone between the pastoral zone and the croplands, are on the increase. This is also apparent in other countries as burgeoning human and livestock populations put more and more pressure on the shrinking arable land base (El-Beltagy, Saxena and Wang 2008).

[۱]-Sandification refers to sandy desertification. It is experienced in many areas of China from the sub-humid Hulunbir grasslands in NE China to the edges of the various deserts in western and northern China.