Study On The Evolution Characteristics Of Water And Vegetation In The Area Of Energy Base Of Ordos, Inner Mongolia

Locating in the zigzag of the Yellow River, the energy base of Ordos in Inner Mongolia has an arid and semiarid continental monsoon climate. Since the arid climate of this area, the poor precipitation, the strong evaporation, the scanty vegetation, the desertification ground surface, the severe water loss and soil erosion,with the economic development of energy base, the scarcity of water resources has become a barrier of the local energy base construction. As is known to all, vegetation is a positive factor of preventing the water loss and soil erosion and the index mark of ecological condition since the alteration of vegetation could reflect the change of ecological condition. After generalized many domestic and foreign documentations, this paper analyses the ecological vegetation and the space distribution of waters and their secular change tend so far from 1970s in the macro-scale area, based on landsat data and the US National Aeronautics and Space Administration's newest MODIS NDVI data and the meteorologic and hydrographic data of the study area.The main research findings as follows:1. From the 1960s to 2000, the volume of runoff and base flow of WuDing river's drainage area shows an downtrend which has certain effect to the reducing volume of the Yellow river's runoff. The volume of base flow's space distribution of desert is greater than loess plateau's.2. In Ordos study area of NeiMeng, the lakes'size petered out from 1970s. The shrinking volume's space distribution feature correlated to elevation. The lakes which shrink greater always located in the high elevation area, where is near the area water shed. However, the lakes which shrink less always located in the low elevation area, where is the drainage area.3. In the study area, the vegetation rise from 1980. The improvement amplitude from 1980 to 1990 is not apparent. After 1990 the vegetation NDVI data is apparently rising which means the vegetation's rising tendency is significant. Annually, the vegetation grow from April and grow best in July, August and September. The grow trend of vegetation is lower than the wilting speed after autumn.After analyzing the change trend of water, vegetation, weather and hydrology, this dissertation concludes that the growing of vegetation is the main reason that contributes to the lakes shrinkage located in the energy base of inner Mongolia.