【作者】 刘燕；

【导师】 刘康；

【作者基本信息】 西北大学 ， 自然地理学， 2010， 硕士

【摘要】 本文以位于渭河平原水蚀区与黄土高原沟壑水蚀区交错带的韩城市为研究区。在地理信息系统(GIS)软件的支持下,根据通用水土流失方程(USLE),对韩城市水土流失敏感性进行了评价,并分析其敏感性等级在地理空间上的分布状况,同时也对韩城市潜在水土流失敏感性进行了分析评价。在流域区划的基础上,评价各流域水土流失敏感性。通过本文的研究可以为韩城市水土流失预防和治理提供有益的参考,对整个渭河平原与黄土高原沟壑水蚀区交错带的环境改善提供科学依据。首先,通过对各水土流失敏感性的影响因子进行了计算分析,得到的各水土流失单因子敏感性等级的空间分布；再将各单因子的敏感性等级赋值进行叠加运算,得到韩城市水土流失敏感性各等级空间分布规律,同时,在不考虑地表覆盖因子的前提下,计算出韩城市潜在水土流失敏感性空间分布规律；最后,利用ArcGIS的水文分析工具,将研究区划分为4个小流域,按照韩城市水土流失敏感性值的计算方法,得到各流域的水土流失敏感性值,并对各流域水土流失的敏感性进行分析评价。经过运算分析,韩城市降水侵蚀力和土壤可蚀性单因子敏感性等级普遍偏高,中度敏感以上等级分别占研究区总面积的60.3%,78.46%；地形和地表覆盖单因子敏感性等级土壤可蚀性单因子敏感性等级总体上较低,中度敏感以下等级分别占研究区总面积的65.88%,63.63%。在此基础上,韩城市水土流失敏感性等级以轻度敏感和不敏感等级为主,分别占研究区总面积的52.76%,45.81%,其中,中部浅山丘陵区敏感性等级高于西北部深山区和东部河谷川道,这与韩城市潜在水土流失敏感性等级的空间分布相似。但在韩城市潜在水土流失敏感性中,中度敏感以上等级的分布面积有不同程度的提高,特别是中度敏感等级的分布面积增加到340.93km2。另外,各流域水土流失敏感性总体上也呈现与韩城市水土流失敏感性相似的空间分布特征。本文通过采用GIS技术对区域水土流失敏感性进行评价,可以更加方便、实时提取各敏感性因子,提高了水土流失敏感性评价的时效性,科学性。更多还原

【Abstract】 This paper take Hancheng as study area, which located at the ecotone between the Weihe River plain water erosion area and the Loess Plateau gully erosion zone. In Geographical information system (GIS) software’s support, according to the general soil erosion equation (USLE), has appraised the soil erosion sensitivity in Hancheng, and analyzes its sensitive rank in the geography space distributed condition, simultaneously has also analyzed the potential soil erosion sensitivity in Hancheng. In the basin regionalization’s foundation, appraises various basins soil erosion sensitivity. May provides the beneficial reference of Prevention and government for soil erosion in Hancheng and provide the scientific basis for environment improvement in the entire ecotone between the Weihe River plain water erosion area and the Loess Plateau gully erosion zone, through this paper research.First, through to various soil erosion sensitive influence factor computation analysis, obtain the single-factor spatial distribution of soil erosion sensitivity; Then assignment for overlay operations for the sensitivity level of the single-factor, obtains distribution of various grades of sensitivity to soil and water loss in Hancheng. Simultaneously, in did not consider that the surface cover factor, calculate the sensitivity spatial distribution of the potential soil erosion sensitivity; Finally, through the hydrology analysis tool of ArcGIS, divided into four small basin of the study, according to the soil erosion sensitive value’s computational method of Hancheng, obtain the various basins soil erosion sensitive value, and appraise various basins soil erosion’s sensitivity.After the operation analysis, rainfall erosivity and soil erodibility are generally high level of single-factor sensitivity in Hancheng, more moderate level of sensitivity account for 60.3% of total area,78.46%; Terrain and land cover single factor sensitivity level single factor of soil erodibility generally lower sensitivity level, below moderate level account for the research area total area separately 65.88%,63.63%. On this basis, soil sensitivity by light-sensitive and insensitive level primarily, accounts for the research area separately 52.76%,45.81%. The sensitivity level of central shallow mountain area is higher than the mountain valley in northwest and eastern valley area, this is similar the potential soil erosion sensitivity level’s spatial distribution. But the distribution area of above moderate sensitive level is enhanced of potential soil erosion of sensitivity in Hancheng, specially the moderate sensitive level’s dispersal area increases 340.93km2. Moreover, the spatial distribution characteristic of various basins soil erosion sensitivity also presents as a whole with the soil erosion sensitivity similar of Hancheng.This paper evaluate the sensitivity of the regional soil erosion through the GIS technology, it can be more convenient, real-time extraction of the sensitivity factor, improves the timeliness and scientific of soil erosion sensitivity evaluation.更多还原