【作者】 李滨勇；

【导师】 史正涛；

【作者基本信息】 云南师范大学 ， 自然地理学， 2007， 硕士

【摘要】 松华坝水源区一直是滇池流域最主要的汇水区。流域内的松华坝大型水库是昆明城市生活用水和工业用水的主要水源。随着昆明市城市、人口、经济的高速发展,水资源供给不足、水质污染等问题日益突出。因此,科学地探讨土地利用/覆被变化对地表径流的影响,对于昆明市的供水安全以及滇池的污染治理具有一定的参考价值;同时也可为滇池周边地区工农业发展、土地利用和城市规划等问题的决策提供可靠的科学依据。本研究以松华坝水源区作为研究对象,以Landsat TM遥感影像解译得到的两期(1992年、2001年)1∶10万土地利用图为基础,基于GIS的叠加分析功能,建立了两个时期的土地利用类型转移矩阵;并分析了研究区域近十年的土地利用变化方向、幅度及其驱动力。利用土地利用、土壤、气象等数据库来驱动SWAT水文模型,模拟了松华坝水源区1992年～2001年期间逐年、逐月的地表径流;并以实测值对该模型进行了参数率定,从而证明了SWAT模型适用于松华坝水源区土地利用/覆被变化水文效应的研究。基于率定好的模型,预测了在假定的四种土地覆被情景下,地表径流的变化情况;并以此为依据来探讨不同土地覆被变化对地表径流的影响机制。本文得出以下结论:(1)该水源区土地利用类型以林地为主,其次是草地和耕地,这3类面积的总和达到了整个流域面积的86.40%以上。1992年～2001年期间,土地利用类型转移以耕地、草地及未利用土地向林地的转换为主。转化为林地的耕地、草地、未利用土地分别占1992年各自类型面积的27.42%(2791.08 hm~2)、36.59%(5633.01hm~2)、30.01%(601.29 hm~2)。而其余各类土地类型面积均呈减少状态。(2)对不同坡度等级土地利用的变化分析表明:各个坡度内的林地均有大幅度增长,特别是在6°以上的各坡度段,增长幅度较大。相反,草地和未利用土地在各坡度段内均呈大幅度减少状态。虽然退耕还林取得了较大成效,但是6°以下的耕地面积仍有小幅度增长,这主要是因为人口规模扩大和人类生产、生活活动所导致。(3)应用SWAT模型对1992年～2001年,逐年、逐月地表径流进行模拟时,年际模拟结果最为理想。对于逐月模拟结果,丰水期的模拟值与实测值比较吻合,枯水期差异较大。(4)针对四种土地覆被情景,运用SWAT模型模拟结果表明:情景1(S1)导致径流深增加幅度最大,但是会引起严重的水土流失。在不同程度封山育林的情景S2、S3、S4中,S3更能增大地表径流量。(5)从长远利益来看,搬迁人口比居民转产,更有利于松华坝水源区内的水源保护。目前的封山育林、退耕还林还草工作对于保护水源区的水量、水质具有重要意义。但是在考虑保护水源区水质和增加流域可用水量的有效供给时,应进行合理的植被建设规划;在不同坡度地段,合理地进行植被建设。更多还原

【Abstract】 Songhuaba water source conservation region has been the main catchment of Dianchi Basin in Kunming city.Songhuaba reservoir is one of main water sources of Kunming City’s industry and life 1.With the high-speed development of the city, population and economies,shortage and pollution of water have become serious problems.Therefore,scientifically discussing the different LUCC(land use/land cover change) impacts on the surface runoff is of more reference value for ensuring the safety of water supplying in Kunming City and controlling the pollution of Dianchi Basin.In addition,it can provide theoretical foundation for the development of agriculture and industry,and also for the planning.of land use and city development near Dianchi watershed.This research chooses Songhuaba water source conservation region as the studying object.The conversion matrix of land use change in 1992 and 2001 has been established through the overlay analysis functions of GIS,based on the 1:10,000 land use maps interpreted by the imageries of Landsat TM of 1992 and 2001.Furthermore direction,magnitude and driving force of LUCC of nearly ten years in the study region has been analyzed.Using database of land-use,soil,weather to drive the SWAT model,we have simulated surface runoff of Songhuaba water source conservation region from 1992 to 2001 month by month,year after year.And the SWAT model has been calibrated by the measured values.The results show that the SWAT model is able to be used for the study of LUCC hydrology effects in Songhuaba water source conservation region. Based on the model which has been calibrated,we have forecasted the surface runoff under the 4 hypothesises of LUCC scenarios.Finally,we discussed the effects of different LUCC on the surface runoff..we drew the following conclusions:(1)The main land use type in Songhuaba water source conservation region is forest land;and farm land and grass land.are in the next place.The area of the three land use types account for over 86.4%of the whole basin area.The main changes of land use types in this area are from cultivated land grass land and no-use land to forest land during 1992 to 2001.The area of cultivated land,grass land and no-use land which have changed into forest land account for 27.42%(2791.08 hm~2),36.59% (5633.01 hm~2) and 30.01%(601.29 hm~2) of their area in 1992 respectively.The area of other types of land use remain decreasing.(2)The study of LUCC in different slope indicate that the area of forest land in every slope degree increased obviously,especially above the slope degree of 6°. Contrarily,the area of grass land and no-use land in all the slope degree decreased. Although the converting cultivated land to forest land or grass land has began to exert effect,the area of the cultivated land below the slope degree of 6°has still increased a little.It is caused by the expanding of population and the behavior of pepole’s live and production.(3)When the surface runoffs from 1992 to 2001 are simulated by SWAT,the annually results are optimal.The simulated results of month after month show that the model value coincides with the measured value during the flood period,but there is a great discrepancy between them during the dry period.(4)For the four land use change scenarios,the simulated results by SWAT show that surface runoff can increase most in scenario 1,which following by seriously soil and water loss.In S2,S3 and S4 for closing hill for forestation in different level,S3 can increase surface runoff more obviously.(5)In a long run,moving the people of Songhuaba water source conservation region to other places is more benefit for protecting the water of the water source conservation region than making them engaging other work.At present,it is important for protecting the quantity and quality of water of Songhuaba water source conservation region to close hill for forestation,converte cultivated land to forest land and grass land.But when to protect water quality and increase surface runoff are considered,we should carry on the reasonable planning for vegetation and vegetation construction in the basin.更多还原