The Environmental Implications of Soil Erosion in the United States

Soil erosion has both on-farm and off-farm impacts. Reductionof soil depth can impair the lands productivity, and thetransport of sediments can degrade streams, lakes, and estuaries. Since 1933, soil conservation policies have existedin the United States. Originally they focused on the on-farmbenefits of keeping soil on the land and increasing net farmincome. Beginning in the 1980s, however, policy goalsincreasingly included reductions in off-site impacts of erosion.As a consequence of conservation efforts associated withexplicit U.S. government policies, total soil erosion between1982 and 1992 was reduced by 32% and the sheet and rillerosion rate fell from an average of 4.1 tons per acre per yearin 1982 to 3.1 tons per acre in 1992 while the wind erosion ratefell from an average of 3.3 tons per acre per year to 2.4 tonsper acre per year over the same period. Still, soil erosion isimposing substantial social costs. These costs are estimated tobe about $37.6 billion annually. To further reduce soil erosionand thereby mitigate its social costs, there are a number ofpolicy options available to induce farmers to adopt conservationpractices including education and technical assistance, financial assistance, research and development, land retirement, andregulation and taxes.     

Integration of Case Studies on Global Change by Means of Qualitative Differential Equations

We present a novel methodology to integrate qualitative knowledge from different case studies on Global Change related issues into a single framework. The method is based on the concept of qualitative differential equations (QDEs) which represents a mathematically well-defined approach to investigate classes of ordinary differential equations (ODEs) used in conventional modeling exercises. These classes are defined by common qualitative features, e.g., monotonicity, signs, etc. Using the QSIM-algorithm it is possible to derive the set of possible solutions of all ODEs in the class. By this one can formulate a common, qualitatively specified cause–effect scheme valid for all case studies. The scheme is validated by testing it against the actually observed histories in the study regions with respect to their reconstruction by the corresponding QDE. The method is outlined theoretically and exemplary applied to the problem of land-use changes due to smallholder agriculture in developing countries. It is shown that the seven case-studies used can be described by a single cause–effect scheme which thus constitutes a pattern of Global Change. As a generally valid prerequisite for sustainability of this kind of land-use the presence of wage labor is shown to represent a decisive factor. This revised version was published online in July 2006 with corrections to the Cover Date.     

Combating Desertification: Building on Traditional Knowledge Systems of the Thar Desert Communities

The Thar Desert of western India is known for its rich and ancient culture system and traditions. The communities have long been part of the Thar Desert ecosystem and have evolved specific strategies to live in harmony with its hostile environment. This culture has provided several miracle plants of immense food and medicinal value to modern civilisation. The ancient rural livelihood knowledge system reflects time-tested techno-scientific knowledge with a proven track record of sustainability, especially during natural hazards like drought and famines. In addition, several of the traditional skills of local communities in arts and crafts, music and instruments have made modern man aware of the art and techniques of sustainably utilising local biological resources and preserving their biodiversity along with using waste products of the forests, without harming the desert ecosystem. Traditional cultural and socio-religious values are fast dwindling under the impact of materialistic approach, industrialisation and development. This paper endeavours to illustrate the need to assist and propagate indigenous rural livelihood systems rather than mindlessly replace or abandon them as a result of state bureaucracies.     

额济纳绿洲生物多样性保护与可持续发展对策研究

本文论述了额济纳绿洲生物多样性的基本内涵与保护价值，提出保护绿洲生物多样性的措施及策略。     

持续农业的新发展--生态农村的建设

本文分析了现今农村影响农业持续发展的因素 ,提高建立高产优质高效生产体系以及提高资源利用率的技术措施和优化物质循环转化环节等三项生态村建设的必备条件与对策。阐述了全村总体型和家庭生态型二种建设模式的基本原理与设计原则 ,并详细介绍了城郊型生态村 ,山区型生态村 ,庭院型生态村模式。     

城市小区分散式生态污水处理

针对目前我国城市集中式污水处理方法的弊端，提出将小型人工湿地运用于城市小区的污水处理，形成分散式生态污水处理系统，实现环境目标与经济效益的结合。     

清洁生产与循环经济

将实践和理论结合阐述了循环经济理论的理念及循环经济和清洁生产的关系。实现循环经济理论在技术层面应当开发和应用3种技术：清洁生产技术，末端治理技术和报废产品回用技术；在社会层面应当发挥政府和公民两方面的作用。在我国当前国情条件下，实施循环经济的重点是：扎扎实实地推行清洁生产，开展废旧物品的回用。政府的职责是制定实施循环经济的法规，宏观规划；民众应提高循环经济和可持续发展的意识，自觉地可持续消费。     

透视我国环境与资源法制建设

我国自改革开放以来在构建环境与资源保护法律体系方面取得了可喜的成绩,但也存在一些问题。主要表现为:可持续发展战略尚未成为我国环境与资源保护立法的指导思想,我国的环境与资源立法不能完全适应社会主义市场经济的要求和社会发展的需要,我国关于环境与资源的法律法规之间不相统一。造成上述问题的原因有外部因素和内部因素,同时我国的具体国情又使它们更具特殊性。为了有效地解决这些问题,我国须在加强环境立法、健全现有制度、协调内部功能等方面进行不懈的努力。     

Living with Pollution in Egypt

Environmental issues are increasingly discussed in Egypt, and there is some progress in dealing with pollution. This paper examines the environmental understandings of Egyptians living in four localities. People are preoccupied with such pollution problems as dirty streets, dirty air and water, and noise, for they aspire to live in a clean, healthy environment. To achieve this, they pressure the government, and take certain individual and collective actions themselves, although direct political action is rare.     

Sustainable Development and Environmental Impact Assessment in Egypt: Historical Assessment

The achievement of sustainable development demands the integration of environment and development. To achieve sustainable development requires a close collaboration and cooperation between environmentalists and the decision-makers. The evidence is that in developing countries (Egypt, as an example) the gap is widening rather than closing. Intensive research programs are needed, for instance in the field of sustainable development and urban environmental management, to narrow that gap. Environmental Impact Assessment (EIA) has become a management tool for achieving acceptable forms of environmentally sound development and sustainability; at best it is proving nothing more than a permit to move a project ahead.It is recommended that indicators for sustainable development and their progress be fully monitored. Performance indicators should always be established, not only for project implementation, but also during and after the implementation process to make sure that all mitigation measures are satisfactorily implemented. This can be achieved by linking the license granting authority for action to the actual implementation of these measures. To secure the environmental sustainability of an environmental project, it is also important to have the EIA document as an integral part of the license application document, and to make it available to inspectors during their necessarily frequent inspection visits.