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1.
/ Why are some environmental risks distributed disproportionately in the neighborhoods of the minorities and the poor? A hypothesis was proposed in a recent study that market dynamics contributed to the current environmental inequity. That is, locally unwanted land uses (LULUs) make the host communities home to more poor people and people of color. This hypothesis was allegedly supported by a Houston case study, whereby its author analyzed the postsiting changes of the socioeconomic characteristics of the neighborhoods surrounding solid waste facilities. I argue that such an analysis of postsiting changes alone is insufficient to test the causation hypothesis. Instead, I propose a conceptual framework for analysis of environmental equity dynamics and causation. I suggest that the presiting neighborhood dynamics and the characteristics of control neighborhoods be analyzed as the first test for the causation hypothesis. Furthermore, I present theories of neighborhood change and then examine alternative hypotheses that these theories offer for explaining neighborhood changes and for the roles of LULUs in neighborhood changes. These alternative hypotheses should be examined when analyzing the relationship between LULUs and neighborhood changes in a metropolitan area. Using this framework of analysis, I revisited the Houston case. First, I found no evidence that provided support for the hypothesis that the presence of LULUs made the neighborhoods home to more blacks and poor people, contrary to the conclusion made by the previous study. Second, I examined alternative hypotheses for explaining neighborhood changes-invasion-succession, other push forces, and neighborhood life-cycle; the former two might offer better explanation.KEY WORDS: Environmental equity and justice; Locally unwanted lane uses; Siting; Market dynamics; Invasion-succession; Neighborhood changes  相似文献   
2.
/ The Galilee region on the northern edge of Israel constitutes more than 15% of the state's territory, supplies more than half of its drinking water needs, and is an important recreational resource and destination for Israelis. One of the main objectives of the plan for the Galilee was to devise a regional physical and economic development strategy for the years 1992-2007 that would arrest the trend of emigration of its residents, attract newly arrived immigrants to the region, and at the same time protect natural resources and environmental quality. This paper is limited to discussion of the environmental aspects of the plan. It analyzes spatial concepts for distribution of projected population growth, evaluates environmental impacts of alternative plans, and proposes a decision-making framework and tools for minimizing natural resources loss from development at the local level. Assessment of potential environmental impacts generated quantitative data of natural resources areas. Application of the data in the plan evaluation stage showed that the alternative that concentrated most of the new development in central Galilee was the second-best choice environmentally, but was preferred as the best choice for overall qualities. The planning study offers an alternative environmental impact assessment (EIA) process to the one presently used in Israel by incorporating environmental considerations at the initial plan-making stage and not at the plan-approval stage. It demonstrated that in order to be effective, environmental assessment and land-use planning should be seen as one effort that is integrated from the start and in each stage of the plan-making process.KEY WORDS: Environmental assessment; Development planning; Galilee  相似文献   
3.
The California Environmental Quality Act (CEQA) has evolved from a mini-NEPA, first enacted in 1970, into a procedural act that affects the approval process of all large developments in California. In 1990, California local governments produced over 1600 environmental impact reports and 30,000 initial studies under CEQA. Because of its widespread use, CEQA has periodically drawn the attention of the state legislature, most recently in 1993, when over 60 CEQA reform bills were introduced. This paper describes the CEQA process and evaluates its success at meeting its explicit and implicit goals. The research includes a statewide survey of CEQA practice, sent to the planning departments of all 513 local governments in California in 1991. Survey respondents agreed that CEQA helps in evaluating environmental impacts, reducing impacts, informing the public, and coordinating public agency review. It is effective in reducing the environmental impacts of individual projects, but is not as effective in improving environmental quality on an areawide scale. This research concludes that CEQA has led to positive outcomes and is not as deeply flawed as many of its critics claim. Still, CEQA as currently designed may not be the optimal vehicle for ensuring environmental quality.  相似文献   
4.
黄土高原地区生态建设的关键问题   总被引:1,自引:0,他引:1  
从黄土高原地区水土保持生态建设的实际情况出发,结合历史经验教训,探讨了生态建设与农业发展、农民脱贫致富的关系.指出生态环境问题归根结底是人的问题,减少人类对生态环境的破坏和干扰,因地制宜地进行植被建设和生态恢复,激励广大农民自觉参与生态建设对黄土高原地区水土保持生态建设成败至关重要.  相似文献   
5.
火电厂烟气脱硫工程往往是在场地或其他条件受到诸多限制的情况下进行的,设计中总平面布置的作用显得尤其突出。以几个电厂脱硫工程的设计为例,探讨如何充分利用已有务件,协调脱硫与整个厂区总平面布置的关系,以使设计合理,经济。  相似文献   
6.
Throughout history, mining communities have invariably found themselves striving for a good quality of life and a long‐term future. In the 21st century, problems of maintaining the economic vitality of mining regions are now compounded by concerns about the biophysical integrity of the local environment. In regions of the world where the economic viability of the resource is marginal and achieving a reasonable quality of life is a daily struggle, sustainable mining may seem to be a dubious prospect at best. Yet the twin imperatives of global political forces and burgeoning environmental concerns are requiring industry, governments and other interests to re‐conceptualize the way in which mining takes place in communities. Although mining itself may not be seen as an industry that contributes to the achievement of environmental objectives, it could — with careful planning — be used as a tool to foster a more sustainable and healthier community. This argument is considered in the context of the coal mining region of Santa Catarina, Brazil.  相似文献   
7.
● Properties and performance relationship of CSBT photocatalyst were investigated. ● Properties of CSBT were controlled by simply manipulating glycerol content. ● Performance was linked to semiconducting and physicochemical properties. ● CSBT (W:G ratio 9:1) had better performance with lower energy consumption. ● Phenols were reduced by 48.30% at a cost of $2.4127 per unit volume of effluent. Understanding the relationship between the properties and performance of black titanium dioxide with core-shell structure (CSBT) for environmental remediation is crucial for improving its prospects in practical applications. In this study, CSBT was synthesized using a glycerol-assisted sol-gel approach. The effect of different water-to-glycerol ratios (W:G = 1:0, 9:1, 2:1, and 1:1) on the semiconducting and physicochemical properties of CSBT was investigated. The effectiveness of CSBT in removing phenolic compounds (PHCs) from real agro-industrial wastewater was studied. The CSBT synthesized with a W:G ratio of 9:1 has optimized properties for enhanced removal of PHCs. It has a distinct core-shell structure and an appropriate amount of Ti3+ cations (11.18%), which play a crucial role in enhancing the performance of CSBT. When exposed to visible light, the CSBT performed better: 48.30% of PHCs were removed after 180 min, compared to only 21.95% for TiO2 without core-shell structure. The CSBT consumed only 45.5235 kWh/m3 of electrical energy per order of magnitude and cost $2.4127 per unit volume of treated agro-industrial wastewater. Under the conditions tested, the CSBT demonstrated exceptional stability and reusability. The CSBT showed promising results in the treatment of phenols-containing agro-industrial wastewater.  相似文献   
8.
Heterogeneous water phase catalysis as an environmental application: a review   总被引:15,自引:0,他引:15  
Catalytic water phase processes as an environmental application is a relatively novel subject with tremendous potential in the near future. This review of 120 references presents the wide scale of heterogeneous water phase applications studied mainly within past five years. Both oxidation and hydrogenation processes are included as well as TiO2 assisted photocatalysis. According to the references, heterogeneous catalysis is developing rapidly. New bimetallic catalysts and supports with higher surface area have improved catalytic efficiency in both oxidation and hydrogenation processes. It also seems that study on use of some waste materials such as red mud as catalyst is a very progressive field. On the whole, the chemical aspects are pretty well known, but the catalyst durability, and in many cases activity as well, has to be improved.  相似文献   
9.
阐述了污水低氧脱氮的基本原理,即抑制或去除亚硝酸盐氧化菌(NOB),同时保留氨氧化菌(AOB),并保持其活性;探讨了污水低氧脱氮实现途径;详细介绍了几种典型的污水低氧脱氮工艺(短程硝化(SHARON)工艺、厌氧氨氧化(ANAMMOX)工艺、好氧反氨化(DEMON)工艺、低氧自养硝化反硝化(OLAND)工艺、甲烷营养型硝化反硝化工艺和亚硝酸盐型完全自养脱氮(CANNON)工艺)的应用研究进展;最后对污水低氧脱氮处理工艺的工程运用进行了展望.  相似文献   
10.
Environmental degradation by mud in tropical estuaries   总被引:3,自引:0,他引:3  
In wet tropical countries, the intense rainfall and the lack of effective restrictions on human activities in the river catchment leads to increased rates of soil erosion. This has increased the sediment loads many times over from the natural level. As a result, estuarine and coastal waters are becoming increasingly muddy with associated losses for society in terms of increased flooding and a degradation of the environment, the fisheries and the economic use of these waters. It is suggested that science-based models be used to predict the fate of mud in estuaries and coastal waters when planning development in river catchments, particularly in wet tropical countries. This would help integrate land and water management. Modelling technology is demonstrated by a combination of field and model studies in four turbid tropical estuaries, namely the Fly River in Papua New Guinea, the Mekong River in Vietnam, the Cimanuk River in Indonesia, and Hinchinbrook Channel in Australia. The final model is adapted to local conditions and extensively uses data assimilation especially for open boundary conditions. There can be a feedback between the hydrodynamics and the mud dynamics when the system silts; in wet tropical countries this can occur rapidly, sometimes in only 30 years. Electronic Publication  相似文献   
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