【作者】 姚志宏；

【导师】 巩恩普； 姚玉增；

【作者基本信息】 东北大学 ， 矿产普查与勘探， 2008， 硕士

【摘要】 土地是人类赖以生存的基础,但是日益严重的土地退化正严重制约着人类的发展。土壤侵蚀导致土地资源遭受破坏、粮食减产、灾害发生、土壤肥力下降；土壤侵蚀形成的泥沙在河道或水库中年复一年的淤积,致使河床抬高,泄洪能力降低,进而导致洪涝灾害。辽宁是我国水土流失较严重的省份之一,土壤侵蚀遍及全省,其中辽西地区尤为严重。本文以辽西建平县境内的老哈河流域为研究对象,以遥感和地理信息技术为主要研究手段,利用TM和ETM+遥感影像及其它资料,分别提取了研究区土地利用、植被盖度、坡度、土壤可蚀性、岩性、地质灾害等专题信息,应用多因子叠加方法对老哈河流域1990年和2000年土壤侵蚀强度及其演化进行了评价；计算了研究区基于栅格的泥沙输移比,对研究区泥沙输移状况进行了分析。论文主要研究内容及成果如下：1、利用GIS技术,对辽宁省数字高程模型(DEM)进行水文特征分析和流域划分,确定了研究区范围；利用遥感处理软件ERDAS8.7分别对TM和ETM+遥感影像进行几何纠正、解译,提取了研究区土地利用类型及植被覆盖度专题信息；分别从研究区DEM、土壤类型图、地质图及地质灾害图中提取坡度、土壤可蚀性、岩性和地质灾害专题信息。2、借鉴国内外土壤侵蚀的研究模型,根据研究区自然环境背景,选取土地利用类型、植被盖度、坡度、土壤可蚀性、岩性和地质灾害作为评价因子,采用层次分析法确定因子权重,利用多因子叠加方法对研究区1990年和2000年土壤侵蚀状况及其演化进行了评价。结果表明研究区强度以上侵蚀面积有所减少,侵蚀总面积有所增加。在空间上,研究区中部从昌隆镇以南地区一直向东南延伸到张家营子镇,这一带土壤侵蚀明显好转,老官地镇、烧锅营子、北二十家子镇也明显好转,而黑水、马场南部以及三家等地区侵蚀状况有所恶化。3、应用通过计算泥沙迁移时间来确定SDR的模型,求出基于栅格的研究区泥沙输移比空间分布。该模型在辽宁省内的流域泥沙输移比研究中尚属首次应用。4、建立了泥沙输移空间分布模式：Mi=SDRi×Si。确定了研究区泥沙输移强度分级图。结果表明,研究区北部的老官地、哈拉道口及烧锅营子等地是主要的产沙源,中东部和南部的河道两侧是高输移比区,因此产沙也较多。5、对老哈河流域泥沙输移空间分布特征进行了评价,结果表明泥沙输移强度分别随着土壤侵蚀强度和坡度的增加而增加；不同土地利用类型中泥沙输移强度由弱到强的顺序大致为：居民点<水体<林地<草地<耕地<未利用地<裸地。因此在泥沙防治工作中,应该把这些因素也作为重点考虑对象。更多还原

【Abstract】 The land is the important fundament for human’s living, but the gradually increasing problems of land degradation are becoming serious constraint in human development. Soil erosion causes the destruction of land resources, decrease in grain production, disasters and declines in soil fertility. The sand caused by soil erosion fills up in the river or reservoirs year after year, and result in floods. Liaoning province is famous for serious soil erosion in China. Soil erosion happens nearly all over the province, especially in the west.The Laohahe river basin in the western Liaoning is chosen as topics in the thesis, the remote sensing and geographic information technology is used as major tools, and six factors, i.e., land use, vegetation, slope gradient, soil, lithology and geological disasters derived from TM and ETM+ images and other data are selected. The spatial distribution of soil erosion and sediment delivery of the basin in 1990 and 2000 are calculated by weighted overlay method. The main contents and achivements of the thesis are as follows:1.Based on the hydrology model in ArcGIS, the boundline of the study area is obtained via analyzing the hydrologic characteristics of the Liaoning digital elevation model (DEM). The TM and ETM+ images in the study area are rectified by RS processing software ERDAS8.7. Land use and vegetation coverage are gotten from the images, and slope, soil, lithology and geologic disaster information are derived from other maps separately.2. Soil erosion intensity and its change from 1990 to 2000 are evaluated by weighted overlay method which chooses the land use, vegetation coverage, slope gradient, soil, lithology and geological disaster as factors according to the study models of soil erosion and the facts in the study area. The weights of various factors are determined by AHP.The result shows that the acreage of intensive erosion reduced, but the total area of erosion increased. In the spatial distribution, soil erosion was meliorated obviously in the area from south of Changlong town to Zhangjiayingzi town, and also in Laoguandi, Shaoguoyingzi, Beiershijiazi, while deteriorated in Heishui, south of Machang and Sanjia.3.The SDR of the basin based on grids is obtained by calculating the sediment travel time. This model is firstly used in the sediment delivery study of drainage basin in Liaoning province.4. The spatial distribution model of sediment delivery is established:Mi=SDRi×Si. The charts of sediment delivery distribution of Laohahe river basin in 1990 and 2000 are gotten, which indicate that the northern part of the area is the major sediment source, also the both sides of rivers contribute much more to the sediment yields because of high SDRs in these areas.5.The analysis on spatial distribution of sediment delivery indicares that the sediment delivery intensity enhances with the increasing soil erosion intensity and slope. In different types of land, the sediment delivery intensity increases in the following order:resident< water<woodland<grassland<cropland<unused land<bare land, thus more attention should be paid to these aspects in controlling the diastral sediment.更多还原