【作者】 盛前丽；

【导师】 关君蔚； 张洪江；

【作者基本信息】 北京林业大学 ， 水土保持与荒漠化防治， 2008， 博士

【摘要】 近年来,土地利用变化在区域尺度上的资源与环境效应得到了广泛关注。土地利用变化的重要环境效应之一是以水文效应出现的。针对特定区域,弄清土地利用变化与水文变化之间的联系,成为区域资源问题、环境问题及生态问题上政策效应分析的重要手段。本研究在长江中上游地区选取了香溪河流域作为研究区域进行研究,研究香溪河流域不同土地利用方式的产流效应,研究土地利用变化对河川径流的影响,研究降雨时空分布、森林植被对降雨的调节作用,对于认识其水土资源特点和产流规律,提高对水资源敏感性、脆弱性研究,据以采取相应防治对策具有重要意义。论文选择使用了分布式水文模型(SWAT)对香溪河流域的径流响应进行模拟研究。基于地理信息系统技术,建立了香溪河流域的空间数据库(包括数字高程模型、土地利用图、土壤类型图等)和属性数据库(包括降雨、气温、风速、相对温度)。根据DEM和水系分布图由模型自动将整个研究区划分为17个子流域,根据子流域内优势土地利用覆被和优势土壤类型,设定土地利用和土壤阈值都为10%,在流域内划分出115个水文响应单元。利用1971～1989年实测水文资料进行了模型参数的校准和验证,年径流校准期和验证期的相关系数分别为0.77和0.83,Nash-Suttcliffe系数分别为0.72和0.67,月径流校准期和验证期的相关系数分别为0.82和0.77,Nash-Suttcliffe系数分别为0.77和0.74,结果表明实测径流和模拟径流的线性回归系数和模型的效率系数满足模型模拟的要求,该模型适用于研究流域。基于SWAT模型的模拟分析结果,以85年为例,对香溪河流域不同土地利用方式对径流的贡献进行了对比分析,得出坡耕地产生的径流深最大,637.5mm,梯田或平原耕地次之,林地最小,为546.99 mm。最大的坡耕地为最小的林地的1.16倍。采用固定一个影响因子,来研究另一个影响因子对径流的影响。论文分析了土地利用变化对径流的影响,模拟结果表明,在相同的降雨条件下,90年代的土地利用方式与80年代的土地利用方式相比,径流量减少。采用情景分析法,分别模拟了不同水文年和不同森林覆盖率条件下的降雨径流关系。结果表明径流量随降雨量的增加而增加,随着森林覆盖率的增加,径流量减少。更多还原

【Abstract】 In recent years, response of resources and environment to land use change arouses broad attention in region scale. One of responses of environment to land use change is hydrolody response. In given region, making clear the relation of land use change and hydrology change is a main measure, which is used to analyse policy domino offect in region resources, environment and zoology matters. The paper chooses Xiangxi River watershed as the example to study the response of the various landuse to runoff runoff, the influence of land use change to river runoff, space-time distribution of precipitation and adjustment of ruoff by forest cover. The results were of important meaning to understand the characteristics of water and soil resources and the rule of runoff producing and to improve the research on the sensitivity and frangibility of water resourses, according to which to take corresponding measures.The paper choosed distributed hydrological model SWAT (the Soil and Water Assessment Tool) to simulate and study the hydrologic response in the research area.Based on GIS, the spatial database (integrating DEM, soil, and landusemap et al.) and non-spatial database (integrating climate, and land management data et al.) were established.With the support of SWAT model, the 17 sub-watersheds have been automatically delineated by the DEM and waterstreams. And the model has been calibrated and validated with the real data collected from the study area in the years from 1971 to 1989. In calibration and validation period occurred in years, relative coefficient are 0.77 and 0.83, Nash-Suttcliffe coefficient are 0.72 and 0.67, In calibration and validation period occurred in momths, relative coefficient are 0.82 and 0.77, Nash-Suttcliffe coefficient are 0.77 and 0.74. The results show that SWAT model could be successfully used to model this area.Based on simulating results, taking Xiangxi River watershed as the example, the paper analysed contribute of various land use to runoff. The result indicated that the runoff depth produced by gradient plantation was the most,(637.5mm), terrace plantation taked second place and woodland was the lest (546.99mm).The most, gradient plantation, was 1.16 times of the least, woodland.The paper studied another factor by fixupping one factor, which affected runoff. It analyzed the influences of landuse change runoff. The result showed that the sum of runoff was disceased by the change of land use from the circumstance in 1980s to 1990s.Adopting scenes analyse method to simulate the relationship of precipiotation and runoff under the condition of various precipitation and forest cover.The result showed runoff increased along with prepication increasement and decreased along with forest cover increasement.更多还原