The Desertification And Cause Analysis Of Daliuta Area Of Shaanxi Province

DaLiuta area is the main body of the Northern part of ShenMu Coal mine of ShenFu-DongSheng coalfield, and based on it the combination of coalmine, energy and chemical has founded. The coal mine exploitation accelerates the local economic development, but simultaneously brings severe environmental geology problems. Desertification which is intensely controversial was chose to study, and the origin, evolvement, development in late 20 years and the cause of formation was analyzed.Firstly, the Grain-size of four sections of Huojitu, Daliuta and so on, was analyzed to get the sedimentary character and process of desertification. Besides, the newest 1:25000 SPOT5 remote sensing image of 7,2005 was used to survey and validate, and then contrast with the TM images of 1986 and 1996 to analyze the situation and the dynamic changes of desertification in the late 20 years. Then, the relationship between geological setting, climate, human activities and desertification was analyzed. Lastly, the trend of desertification was forecasted and some prevention and cure action was given.The four sections of Huojitu, Daliuta and so on, are all constituted by three stratums: ancient aeolian sand, sandy palesol and modern aeolian sand, it reflects Daliuta area had experienced the time of dry and cold when Mu Us desert expanded in the later stage of late Pleistocene epoch or in early Holocene, the fixed of desert in the Holocene Megathermal and the development of desertification in Late Holocene. The desertification of Daliuta area should originate to late-Ming and early-Qing period, and worsen in 20 century, but we found that it reversed between 1986 and 2005 based on the contrast of remote sensing images of 1986, 1996 and 2005. In the history the desertification was serious because the abundance of sand, the bad climate, irrational human reclamation and warfare, but in late 20 years the stabilization of precipitation, ascending of air temperature, subdued of maximal and average of wind speed, all promote the reversion. The policy of government and prevention and cure of coal mine is more significant to the reverse.