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土地利用是引起土壤侵蚀的重要驱动过程。基于1988年和2000年TM影像数据和气候、土壤、植被及DEM等数据,运用通用的土壤流失预报方程(RUSLE),对鄂尔多斯市1988—2000年间的土壤水力侵蚀进行定量估算,揭示期间水力侵蚀的时空变化特点,并对土地利用类型与土壤侵蚀的关系进行分析。结果显示:1988—2000年间,研究区土壤水力侵蚀时空变化较为明显。时间变化上侵蚀强度明显减弱,除了微度侵蚀从53.16%剧增至81.24%以外,中度、强度、极强度和剧烈侵蚀类型均有较大幅度的下降;空间变化亦很明显,2000年与1988年相比,剧烈侵蚀只有准格尔旗东南部还有少量分布,强度侵蚀和极强度侵蚀主要分布在准格尔旗境内。土地利用方式对土壤侵蚀有明显的影响,高覆盖度草地和水域的土壤侵蚀强度较小。此外,不同土地利用类型的平均土壤侵蚀模数和土壤强度指数均有大幅度的下降。其中未利用地的下降幅度最大(68.14%),其次为低覆盖度草地(64.09%),耕地的下降幅度最小(49.62%)。研究结果表明,鄂尔多斯土壤水力侵蚀治理的重点区域是东北部,改变土地利用方式、增加水土保持工程措施、加强采矿迹地的修复重建等是有效防治土壤水力侵蚀的重要措施。
Land use is an important driving force for soil erosion. Based on the TM image data of 1988 and 2000 and the data of climate, soil, vegetation and DEM, the general soil erosion prediction equation (RUSLE) was used to quantitatively estimate the soil erosion during 1988-2000 in Erdos, The spatial and temporal variation characteristics of the land use types and soil erosion were analyzed. The results showed that the spatial and temporal changes of soil erosion during the period from 1988 to 2000 were more obvious. The intensity of erosion on the time change obviously weakened. Besides the slight increase of the micro-erosion from 53.16% to 81.24%, the types of moderate, intense, extremely intense and severe erosion decreased sharply. The spatial variation was also obvious. In 2000 Compared with 1988, there was only a small amount of severe erosion in the southeastern part of Zhunge’er Banner, and intense erosion and extremely intensive erosion were mainly distributed in Zhunge’er Banner. Land use patterns have a significant impact on soil erosion, and grassland and watersheds with high coverage have less soil erosion intensity. In addition, the average soil erosion modulus and soil strength index of different types of land use decreased significantly. Among them, the unused land has the largest decline rate (68.14%), followed by the low-coverage grass land (64.09%) and the lowest decrease rate of cultivated land (49.62%). The results show that the key area for soil erosion control in Ordos is the northeast, and the important measures to effectively control soil water erosion are to change the land use patterns, increase soil and water conservation engineering measures, and strengthen the restoration and reconstruction of mining sites.