平凉市水土流失现状、成因及治理措施

平凉市位于黄土高原中部，是我国水土流失重点区域之一；水土流失面广、量大、时间集中，对平凉市生态环境和社会、经济发展产生了许多不利影响；水土流失的主要原因是自然和社会因素的双重影响；水土保持综合治理是根治水土流失的有效途径，要利用生物措施、工程措施、农业耕作措施以及生态修复措施综合治理。     

松嫩流域水土流失原因分析

松嫩流域是我国重要商品粮基地之一。目前，松嫩流域已成为我国主要商品粮基地中水土流失最严重的地区，水土流失不仅影响粮食生产，而且泥沙淤积河道，恶化环境。给工业生产和交通运输及人民生命财产带来严重危害。     

关于水土流失的几个问题

坡耕地水土流失已对我国危害深远,与此 时,随着经济和社会的发展,城市化过程造成的水土流失和公路建设造成的水土流失也越来越严重,对以上问题作了简要分析,并根据它们的共性和个性提出了相关的水土保持措施。     

我国生态环境退化的问题分析及对策

生态环境退化已经严重阻碍了社会经济的可持续发展，成为各国关注的焦点；分析了我国森林生态系统退化、水土流失、土地荒漠化、湿地萎缩等主要生态退化类型的现状、分布和成因并对我国退化生态系统的恢复与重建提出了基本对策。     

水土保持技术在小流域生态综合治理中的应用分析

由于特殊的自然地理环境及社会经济状况,加之不合理的开发利用,我国水土流失十分严重。分析了水土流失的现状及危害,阐述了水土流失治理的必要性,重点介绍了水土保持技术,并对水土保持技术进行了效益分析。     

黄山市重点小流域水土保持综合治理成效

针对黄山市水土流失严重以及由此产生的一系列社会经济问题，提出退耕还林等一系列水土保持综合治理措施，有效地控制了水土流失，恢复了生态环境，减轻了自然灾害。     

生态环境建设与林业财政政策─—兼议“九五”期间的林业财务工作

一、加速林业建设是改善生态环境的迫切盟要良好的生态环境是人类生存和发展的基本条件。加强生态环境建设，是人类社会发展的必然选择，也是促进经济与社会持续发展的基础工程。经过多年的努力，我国的生态环境建设事业取得了很大的成绩，但由于我国正处在加速工业化和城市化阶段，经济发展的任务很重，加之，对生态环境保护投入的不足，环保能力的提高远远低于经济的快速增长。因此环境质量总体上仍在不断恶化。主要表现在：（一）水土流失越来越加剧。由于森林植被的破坏，水土流失日趋加剧。目前，全国水土流失面积为367万Km2,全国三分…     

怎样解决中国4大水问题

针对中国水资源面临的洪涝灾害、水资源紧缺、水土流失与生态变化和水污染严重4大问题，提出解决中国水资源问题的对策：给洪水以出路，建设节水型社会，充分发挥大自然的自我修复能力，发展绿色经济。     

“失血”的土地──我国水土流失现象透视

■我国是世界上水土流失最严重的国家之一，全国水土流失面积３６７万平方公里，每年有１００多亿吨沃土付诸东流，相当于卷走至少１０００万亩耕地上的一尺厚肥沃的耕作层。■长期以来，我们继承了大禹治水的经验，重治水轻治山，但山水相连，没有青山哪有绿水？■“种瓜...     

退耕还林政策问答

退耕还林的范围是水土流失严重和粮食产量低而不稳的坡耕地和沙化耕地。国家实施退耕还林工程就是要尽快恢复林草植被，防止水土流失，改善生态环境，调整经济结构，增加农民收入。其标准是：     

Soil erosion: cause and effect

Soil erosion is the main reason why desertification is irreversible. Vegetation can regenerate from a degraded state as long as the seed stock remains viable and there is soil for seeds to germinate and grow in. Water and wind are the two main mechanisms by which soil is eroded and transported. Of the two, water has proven experimentally to be the most important in causing soil erosion with long-lasting results. Controlling water erosion, within overall integrated desertification control plans, is thus a top priority if land productivity is to be maintained.     

中国水土流失防治机制的构建与发展

为促进水土流失防治研究,保障生态安全并与社会经济协调发展,探索科学、高效的防治机制,对中华人民共和国成立以来我国水土流失防治机制的演进过程和取得的成就进行了总结和梳理,对存在的机制上的问题进行了分析。建议加强和提升数据服务决策的能力建设、法制化防治工作的管理与协调,建立健全依据科学、行之有效的水土保持生态补偿机制,规范化、制度化、法制化地保障市场机制的稳健、高效运行。     

四川省土壤侵蚀空间分布规律研究

为了摸清四川省土壤侵蚀空间分布情况,依据全国土壤侵蚀分级系统、强度划分体系,利用GIS分析方法对全省土壤侵蚀类型与强度进行了分析。研究结果表明:①土壤侵蚀类型分水蚀、冻融侵蚀和风蚀三类,但侵蚀类型的空间差异明显,水蚀严重区位于川东,冻融侵蚀作用影响区为川西,风蚀影响区为川北一带;②水力侵蚀为土壤侵蚀最主要的类型,影响面积占总面积的87.7%,冻融次之,风蚀影响面积最小;③侵蚀强度分析显示水力侵蚀强度最大,风蚀强度次之,冻融侵蚀对土壤的破坏程度最小;④土壤侵蚀的分布与地貌、海拔、坡度、坡向等地形因素及与人类的活动密切相关。     

Economics of Soil Conservation: The Upper Mahaweli Watershed of Sir Lanka

This paper estimates the benefits and costs of soil conservation in the Upper Mahaweli Watershed of Sir Lanka. The costs of soil erosion control include the implementation costs of control measures, while the benefits are reductions in the costs of soil erosion. In contrast to many studies in developed countries, the on‐site benefit of soil erosion control in Sri Lanka is estimated to be greater than the off‐site benefit While a social benefit‐cost analysis demonstrates that it is socially desirable to implement conservation measures, the private financial analyses indicate that it is feasible for individual farmers to adopt the conservation measures. Despite private economic feasibility, programs addressing farmers' reluctance to adopt soil conservation measures may be preferable to public intervention in soil conservation activities when the on‐site benefits are greater than the off‐site benefits.     

水土流失与贫困相关性的计量分析

简要综述了国内水土流失与贫困相关性方面的研究,基于全国各省域的水土流失面积发生率与贫困发生率的合成面板数据,通过建立经济模型,计量分析发现,地区水土流失面积发生率与贫困发生率高度正相关。同时,两者的动态变化存在区域差异,映射着不同区域的经济发展水平。     

Decision-making in soil conservation: application of a behavioral model to potato farmers in Sri Lanka

Soil erosion is one of the most devastating problems in the upper watershed areas in Sri Lanka. Erosion-prone cultivation of vegetables (especially potatoes) on steep slopes, without soil conservation measures, has become a major problem in the recent past. Soil erosion has significant impacts on on-farm as well as off-farm activities. Although various institutions have launched programs to introduce soil conservation techniques, these have not yielded expected results mainly due to a lack of understanding of the potato farmers’ behavior on investment decisions on soil conservation. Hence the conceptual model on investment decisions on soil conservation was tested in this paper. The analytical results of the generalized least square model indicated the importance of personal and economic, as well as institutional, factors in decision-making in soil conservation. Therefore, obtaining farmer adoption of erosion-control practices will require the use of various implementation tools such as education, subsidies, and technical assistance. Low willingness to invest in soil conservation indicated the necessity for public installation of conservation structures if they are to be widely used in potato farmlands in the upper watersheds in Sri Lanka.     

经验水蚀预报模型的国内外研究进展

土壤侵蚀预报模型是土壤侵蚀科学研究的重点内容之一,其中,水蚀模型又是土壤侵蚀定量研究的重要方法。国内外对水蚀预报模型已开展了大量的研究,取得了显著的进展和成果,经验水蚀预报模型受到众多学者的普遍关注,推动了该模型的不断完善和发展,对于水蚀预报、水土保持和水土资源持续利用有着重要的意义。论文在梳理大量文献基础上,对国内外水蚀预报模型发展进行了对比分析,以期为经验水蚀预报模型的进一步研究和应用提供参考。     

Soil conservation in Swiss agriculture—Approaching abstract and symbolic meanings in farmers’ life-worlds

This paper explores the significance of ‘life-worlds’ for better understanding why farmers adopt or reject soil conservation measures and for identifying basic dimensions to be covered by social learning processes in Swiss agricultural soil protection. The study showed that farmers interpret soil erosion and soil conservation measures against the background of their entire life-world. By doing so, farmers consider abstract and symbolic meanings of soil conservation. This is, soil conservation measures have to be feasible and practical in the everyday farming routine, however, they also have to correspond with their aesthetic perception, their value system and their personal and professional identities. Consequently, by switching to soil conservation measures such as no-tillage farmers have to adapt not only the routines of their daily farming life, but also their perception of the aesthetics of cultivated land, underlying values and images of themselves. Major differences between farmers who adopt and farmers who reject no-tillage were found to depend on the degree of coherence they could create between the abstract and symbolic meanings of the soil conservation measure. From this perspective, implementation of soil protection measures faces the challenge of facilitating interactions between farmers, experts and scientists at a ‘deeper’ level, with an awareness of all significant dimensions that characterise the life-world. The paper argues that a certain level of shared symbolic meaning is essential to achieving mutual understanding in social learning processes.     

福州市饮用水源保护区水土流失风险评价

选择植被覆盖度、地形坡度和土地利用类型来进行水土流失的风险度评价;试验区域为福州市第二饮用水源地山仔库区和塘坂库区;利用Landsat-7ETM 的影像,在计算归一化差分植被指数NDVI的基础上估算水源地保护区的植被覆盖度;利用栅格数字高程模型DEM,计算地表坡度;利用土地利用类型图获取保护区各地土地利用类型的分布;根据水利部部颁标准,对植被覆盖度、坡度和土地利用类型进行分级,建立水土流失风险评价模型,并在ArcGIS 9.0软件支持下,对上述各因子进行叠加分析,得到保护区水土流失评价风险评价;结果表明研究区内生态环境总体保护较好,但存在一定的水土流失现象,生态环境保护还需进一步加强.