干旱区生态环境知识资源中心

Nowadays, desertification is a common major environmental problem confronted by human society. Analysis in dynamic change of desertification is one of the tasks to control it, and the interpretation of desertification data is the base to analyze the dynamic change. Based on the analysis of collected data of geology, geomorphology, soil, climate, hydrology, and vegetation, the author indicates that different periods of desertification degree distribution maps can be obtained by selecting multi temporal TM images of the study area in recent years, which are interpreted by the tool of RS & GIS. Then, Kubuqi desert is researched as a sample and desertification dynamic change is discussed in terms of desertification area changes, spatial changes of desertification levels. The main ideas can be deduced as follows:

1. The results indicate that frequent human activities will speed up the degradation and deterioration of ecosystem in Kubuqi desert where environmental capacity is small.

2. In addition to general engineering and biological measures, tourism development should be taken into consideration to eliminate the root causes of irrational human activities and keep dynamic balance of ecological systems and human environment.

Desertification means land degradation in arid, semi-arid and dry sub-humid areas, causing by various factors like climate variability and human activities; and the land degradation indicates the decline or loss of biological or economic productivity and complexity of rain-irrigated land, irrigable land, grassland, pasture and forest in arid, semi-arid and dry sub-humid areas, due to one or more than one forces ("United Nations Convention to Combat Desertification", 1994). Desertification brings about ecological aggravation like soil erosion, land waste and geological disaster, and further increases the amount of ecological refugees and poor people Ell. Therefore, desertification is a serious environmental problem that restricts the harmonious development of human society.

Desertification also attracts the attention of governments and scholars in a wide range, and previous research results have shown that desertification control is a long-term process. Complete desertification control requires studies on the change level and characteristic of desertification in a certain area during different periods, exploring the causes of desertification, thus, providing references for the prevention and control, promoting harmonious development of regional population, resource and environment. That is a dynamic analysis on desertification, including selection of desertification information in study area, establishment of evaluation index and interpretation. According to the results, strategies should be put forward to eliminate irrational human activities, achieving harmonious development of nature, economy and society((1)).