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以位于青海南部高原高寒草原区的兴海盆地作为研究区,选取气温年较差、年降水量、植被盖度、坡度、坡向、海拔等因素作为冻融侵蚀强度评价指标,运用层次分析法计算各评价指标的权重,采取标准化值赋权重加权求和的方法计算冻融侵蚀强度指数,以等间隔方法对冻融侵蚀强度指数进行分级,获得了研究区冻融侵蚀强度等级类型,并利用Arc GIS的空间分析与统计分析功能对研究区冻融侵蚀的空间分布特征进行研究。结果表明:研究区冻融侵蚀发生的总面积是4784.34 km~2,其中,轻度侵蚀和中度侵蚀居多,分别占冻融侵蚀总面积的32.07%和40.06%;微度侵蚀、强烈侵蚀和极强烈侵蚀占少部分,分别占冻融侵蚀总面积的7.39%、16.08%和4.39%;冻融侵蚀主要分布在研究区的西部,不同的海拔与坡度等级下,4000—4800 m与5—35°冻融侵蚀最集中,其主要发生在高寒草甸、草原,低覆盖草地上冻融侵蚀尤为严重。研究区冻融侵蚀在各个坡向的波动较小,坡向对其影响亦较小。降水量330—455 mm和年较差24.85—26.04℃冻融侵蚀分布最集中。
Taking Xinghai Basin located in the alpine steppe area of southern plateau in Qinghai as a study area, the annual temperature, annual precipitation, vegetation cover, slope, aspect and elevation were selected as the indexes to assess the erosion intensity. The analytic hierarchy process The weight of each evaluation index was calculated, and the index of erosion-erosion intensity was calculated by weighted normalization weighted summation method. The freezing-thawing erosion intensity index was graded by the method of equal interval, and the type of freezing-thawing erosion intensity was obtained. ArcGIS spatial analysis and statistical analysis of the study area of freeze-thaw erosion spatial distribution characteristics. The results showed that the total area of frost and thaw erosion in the study area was 4784.34 km ~ 2, of which mild and moderate erosion were the most, accounting for 32.07% and 40.06% of the total area of frost and thaw erosion respectively. The micro-erosion, Extremely severe erosion accounted for a small part, respectively, accounting for 7.39%, 16.08% and 4.39% of the total area of freeze-thaw erosion; freeze-thaw erosion mainly in the western part of the study area, different elevation and grade, 4000-4800 m and 5- The 35 ° freeze-thaw erosion is most concentrated, which occurs mainly in the frost-thaw erosion on alpine meadow, grassland and low-coverage grassland. The freeze-thaw erosion in the study area is less fluctuating in all aspects and its influence on the slope is smaller. Precipitation 330-455 mm and annual poor 24.85-26.04 ℃ freeze-thaw erosion distribution most concentrated.