【作者】 张继业；

【导师】 伍钧； 王应军；

【作者基本信息】 四川农业大学 ， 环境工程， 2007， 硕士

【摘要】 本研究以岷江水系天全河一级支流——白沙河为研究对象，系统分析了白沙河流域小水电梯级开发的景观要素、景观结构与景观功能影响，构建了流域小水电梯级开发的景观影响综合评价体系，并运用构建的综合评价体系对白沙河流域小水电梯级开发的景观影响进行了评价。研究结果表明：1．白沙河流域小水电梯级开发的景观影响白沙河流域内草地、河流、林地、耕地等自然或半自然景观类型均发生了面积的转移，水电厂、工厂等人工景观均有增加。小水电梯级开发前后，基质均为占绝对优势的林地，基质孔隙率增大，但数值不高，故小水电梯级开发对基质的影响不明显。流域小水电梯级开发后，斑块总体数量减少，平均斑块大小增加，斑块密度减少，斑块总体有连通性增大、破碎度减小的趋势。结果表明，斑块总体指标改变与林地指标改变的相关性很高，林地斑块指标改变与小水电梯级开发有关，而草地、工厂、居民区斑块指标改变与小水电梯级开发没有明显关系。流域内水电站下泄生态流量不足，河宽明显萎缩，水体冲刷下切作用减弱，河道曲度有所降低，走向也发生改变。一些拦河坝下出现减脱水段，下游一些河段水体长期浑浊，某些区域还产生恶臭。水电站运行对河道水体pH影响不明显，但会增加水体生物盐含量，对水体产生一定的增温作用，还会降低发电水体的溶解氧含量。相邻电站引尾水口紧密衔接，还使河道自然裂口质量降低。小水电梯级开发引起河段减脱水，使河流自身的隔离功能减弱。拦河坝则减弱了上下游的纵向连通程度，而引水渠阻断了河道两侧栖息地间的横向联系。中游部分引水渠穿越林地，使林地整体生态价值分割。梯级开发间接引起道路延伸，减弱了道路占地区域陆生与水生动物的联系、减弱了河道对陆生动物的生态承载力。水电梯级开发对景观多样性、优势度、均匀度、分离度增加有较大贡献，但会阻碍景观破碎度的减少。小水电梯级开发对白沙河流域景观稳定性影响不大。流域上游电站边缘对比度普遍较低，中下游电站边缘对比度普遍较高。水电厂边缘对比度大小与其占地面积与所处位置有关。白沙河流域小水电梯级开发主要对河流与林地景观功能产生了明显影响。由于生态水流量减小，引起地下水位降低，使水环境质量变差，不仅影响到河岸植被带调节功能，还扰乱了河流景观栖息地正常的物质、能量与信息的传递。河流廊道宽窄会使某些物种成为入侵种，对一些低生态位的物种构成威胁。此外，小水电站运营期间产生的噪音也会对水生动物造成影响。水电厂形状则会影响生物扩散和觅食过程。小水电梯级开发对河流单个环境功能有的产生正面影响，有的产生负面影响，而对河流景观整体环境功能影响不明显。小水电梯级开发对林地大部分单个环境功能有正面影响，会改善林地景观整体环境功能。2．流域小水电梯级开发的景观影响综合评价体系在系统分析流域小水电梯级开发的景观影响基础上，确定了评价范围，分解了景观影响内容，评选了二十五个评价因子并将其分级、赋权。通过查阅通用分级标准、综合指数分组方法、类比相似评价成果，确定了评判集标准，构建了流域小水电梯级开发的景观影响评价体系。初步构建了流域小水电梯级开发的景观价值损失评估体系。其中，河流景观价值损失主要包括渔业生产、水土流失、泥沙淤积、水质净化和文化娱乐功能等价值损失。林地景观价值损失主要包括林地生产、水源涵养、泥沙流失、固碳放氧、占用林地价值损失和林地恢复费用。3．白沙河流域小水电梯级开发的景观影响评价运用构建的评价体系对白沙河流域进行了评价，结果表明采用该评价体系得出的评价结论比较全面、客观。白沙河流域小水电梯级开发后景观评价等级为良。小水电梯级开发对该流域景观产生的影响不大。运用建立的评估体系对白沙河流域小水电梯级开发的景观影响进行了价值损失评估。结果表明，白沙河流域小水电梯级开发后景观价值总损失为2074.9977万元。提出了景观保护措施，建议主要通过增加水量、提高水质、减少非景观水资源用量来保证景观生态用水量；通过景观水土保持与生态恢复等生态工程技术的实施开展流域景观恢复。更多还原

【Abstract】 Taking the Baisha river which was the first level tributaries of the Tianquan river as the study object, the impact to landscape elements, landscape structure and landscape function of the small hydropower rundle development in Baisha river drainage area were analyzed by the numbers in this study. Then, the comprehensive landscape impact assessment system of small hydropower rundle development in Baisha river drainage area was elementary analyzed. Finally, the landscape impact of the small hydropower rundle development in Baisha river drainage area was assessed by using the comprehensive assessment system designed before. The results were as follows:1. Landscape impact of the small hydropower rundle development in Baisha river drainage areaThe area of grassland, rivers, woodland, farmland and other natural or semi-natural landscapes transfered in Baisha river drainage area. Hydropower, factory and other artificial landscape rose. Woodland was the absolute advantage matrix around the small hydropower rundle development. Porosity of the matrix increased, but the value was not high, so the impact of the small hydropower rundle development to the matrix was not significant.After the rundle development of the small hydropower in Baisha river drainage area, the number and the density of overall patch decreased, the average patch size increased. The trend of patch connectivity was increasing and the fragmentation was decreasing. The results showed that the correlation of the index change between overall patch and woodland was high. The index change of the woodland had something to do with the small hydropower rundle development in Baisha river drainage area. But the patch index change of grassland, factories and neighborhoods had noting to do with the small hydropower rundle development in Baisha river drainage area.The ecological flows discharged were low. The river width shrunk significantly. Water erosion and the curvature of the river reduced, and its heading changed. Some area appeared dehydrated, feculent and stench. The impact of the hydropower to the river pH value was not remarkable on operation period, but it could increase the biology salt content and the warm function of Water. But it could also reduce the dissolved oxygen content of Water. The quoted channel and the tail channel of the neighboring hydropower linked up so close that the quality of the natural breach also reduced. With the development of the small hydropower rundle, it caused the dehydration in some sections of river, and this weakened the isolation function of the river. And the dam weakened longitudinally connection of the river. While, the quoted channel blocked the crosswise relationship between two sides habitats of the river.In the area of the middle reaches of the river, the quoted channel partially passing through the woodland caused the woodland overall ecology value division. The rundle development indirectly caused the path to extend, weakening relation between the land and the aquatic animals in the path region, as well as the ecology supporting capacity of the river course to the land animals.The development of small hydropower rundle had the remarkable contribution to the increasing of landscape diversity, landscape dominance, landscape uniformity, landscape separating degree as well as the landscape reduction of fragmentation. But the impact of the small hydropower rundle development was not remarkable to the stability of the Baisha river drainage area. The edge contrast of the hydropower was generally low in upstream area, and generally high in middle and low reaches of the river. The hydropower edge contrast had something to do with its area and position.The Landscape function of the river and the woodland were mainly impact by the small hydropower rundle development in Baisha river drainage area. As the decreasing of the ecological flows, the ground water level lowed and the water environment quality changed badly. It not only affected the adjustment function of the river bank vegetation belt, but also disturbed the normal transmission of the matter, energy and the information in river landscape habitat. The width of river corridor changing narrow also caused certain species become the invasion, posing the threat to some low ecology position species. In addition, small hydropower producing noise in operation period also impacted the aquatic animals. The shape of hydropower could also affect the biology proliferation and the process of looking for food.The small hydropower rundle development had either positive or negative impact to some single environment function, but the impact was not remarkable to the overall environment function of the river landscape. And the small hydropower rundle development had positive impact to most single environment function, which could also improve the overall environment function of the woodland landscape.2. The comprehensive landscape impact assessment system to the rundle development of the small hydropowerBased on the analysis of landscape impact of small hydropower rundle development in Baisha river drainage area, the assessment scope was determined. Then, the landscape impact content was decomposed, and 25 assessment factors were filtered. And the assessment factor graduation and its significant degree were determined. Through the consult general graduation standard, the composite index grouping method and the analogy similar appraisal achievement, the judgment standard system was determined. Finally, the comprehensive landscape impact assessment system to the development of the small hydropower rundle was constructed.Landscape value loss assessment system of the small hydropower rundle development was initially constructed. The river landscape value loses mainly included the fishery production, soil erosion, the silt filling up, water purification and cultural entertainment function. The woodland landscape value loses mainly included the woodland production, the water source self-control, the silt drains, the fixing up coal and put out the oxygen, occupying value loss and renewing expense.3 Landscape impact assessment of the small hydropower rundle development in Baisha river drainage areaUsing the assessment system, the landscape impact assessment of the small hydropower rundle development in Baisha river drainage area was carried out. The results indicated that the assessment conclusion was comprehensive and objective in the course of using the assessment system. The landscape rank showed good after the small hydropower rundle development in Baisha river drainage area. So the landscape impact of the small hydropower rundle development in Baisha river drainage area was not remarkable.Using the initially constructed landscape value loss assessment system of the small hydropower rundle development, the value loss assessment was carried out. And the result showed that the landscape value loss was 20749977 Yuan after the development of small hydropower rundle in Baisha river drainage area.Landscape protective measures was proposed. It was suggested the landscape restoration should be carried out. First, guarantee the water amount for landscape ecology using by increasing the water amount, enhancing the water quality, reducing the non-landscape water; Second, apply the ecological engineering technology, such as landscape conservation of water and soil as well as the ecology restoration.更多还原