艾比湖地区30多年来土壤侵蚀时空变化规律研究

以遥感与GIS为技术支撑,对新疆艾比湖地区1972-2005年土壤侵蚀进行了动态监测,并对33年来土壤侵蚀时空变化进行分析.研究结果表明.艾比湖地区的土壤侵蚀以风蚀为主.水蚀面积变化不大,风蚀区各强度面积变化明显.其时空变化特征:(1)侵蚀面积1977-2005年总体呈下降趋势,其中1992-2001年侵蚀面积减少显著,且以轻度和强度风蚀减少为主;其次是2001-2005年侵蚀面积减少明显.以中度和轻度风蚀减少为主.只有1972-1977年侵蚀面积有所增加.(2)侵蚀变化速度1977--2005年呈现总体下降,而且1990-2005年下降的速度趋快.(3)侵蚀强度趋于下降.水蚀各强度等级变化很小.风蚀各强度等级变化明显,以强度高的类型向强度较低类型转换为主.究其原因主要是20世纪90年代以来,由于艾比湖水面持续增大和国家一系列生态保护与建设工程的实施,使艾比湖周边风力侵蚀得到有效遏制,区域生态环境明显改善.

Research on Spatial-Temporal Change of Soil Erosion in Ebinur Lake in 33 Years

Based on remote sensing and GIS technology,we monitored the soil erosion area of Ebinur Lake in Xinjiang from 1972 to 2005 and meanwhile analyzed the spatial-temporal changes during the past 33 years. And the results showed that the main type of soil erosion in the area was wind erosion. Correspondingly, the water erosion area changed lightly while different intensity grades of soil erosion area varied distinctly in this area. And the characteristics were as following: Firstly, the erosion area was declining from 1977 to 2005, and especially, the decline was notable in the period of 1992 ?2001 and the erosion intensity grades were mainly light and heavy types. Besides, in the period of 2001 ?2005, the reduction of the area of moderate and light intensity grade soil erosion was the mainly reason for the erosion area decline. However, from 1972 to 1977, the erosion area increased a little. Secondly, the erosion change speed declined from 1977 to 2005 as a whole, moreover, the decline tendency got faster in the period of 1990 ?2005. Thirdly, the erosion intensity grade had a decline tendency. Specifically, water erosion changed a little but wind erosion changed a lot. And the mainly change was from heavy erosion to light erosion. In conclusion, there were two reasons for above erosion characteristics in Ebinur Lake. For one thing, the water surface of the Ebinur Lake was enlarging. For another, the government took a series of ecological protection measures and other construct project to reduce wind e-rosion around the Ebinur Lake. As a result, the local ecological environment got better and better.