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621.
Environmental problems associated with socio-economic development have been growing concerns faced by many regional and/or national authorities. However, effective planning may encounter difficulties since uncertainties existing in a number of impact factors and pollution-related processes are often not well acknowledged and reflected. This study advances an interval-fuzzy chance-constrained programming (IFCP) method for planning regional economic and environmental systems, where uncertainties presented as intervals, fuzzy sets and probability distributions can be tackled. The developed method is applied to a real-world case for economic and environmental planning in the New Binhai District in the Municipality of Tianjin, China. Two scenarios based on multiple environmental constraints are examined. The results can help identify desired alternatives for planning regional development strategies, where compromised schemes are provided under an integrated consideration of economic efficiency and environmental protection under multiple uncertainties.  相似文献   
622.
Booth, Nathaniel L., Eric J. Everman, I‐Lin Kuo, Lori Sprague, and Lorraine Murphy, 2011. A Web‐Based Decision Support System for Assessing Regional Water‐Quality Conditions and Management Actions. Journal of the American Water Resources Association (JAWRA) 47(5):1136‐1150. DOI: 10.1111/j.1752‐1688.2011.00573.x Abstract: The U.S. Geological Survey National Water Quality Assessment Program has completed a number of water‐quality prediction models for nitrogen and phosphorus for the conterminous United States as well as for regional areas of the nation. In addition to estimating water‐quality conditions at unmonitored streams, the calibrated SPAtially Referenced Regressions On Watershed attributes (SPARROW) models can be used to produce estimates of yield, flow‐weighted concentration, or load of constituents in water under various land‐use condition, change, or resource management scenarios. A web‐based decision support infrastructure has been developed to provide access to SPARROW simulation results on stream water‐quality conditions and to offer sophisticated scenario testing capabilities for research and water‐quality planning via a graphical user interface with familiar controls. The SPARROW decision support system (DSS) is delivered through a web browser over an Internet connection, making it widely accessible to the public in a format that allows users to easily display water‐quality conditions and to describe, test, and share modeled scenarios of future conditions. SPARROW models currently supported by the DSS are based on the modified digital versions of the 1:500,000‐scale River Reach File (RF1) and 1:100,000‐scale National Hydrography Dataset (medium‐resolution, NHDPlus) stream networks.  相似文献   
623.
Urban ecological systems: scientific foundations and a decade of progress   总被引:9,自引:0,他引:9  
Urban ecological studies, including focus on cities, suburbs, and exurbs, while having deep roots in the early to mid 20th century, have burgeoned in the last several decades. We use the state factor approach to highlight the role of important aspects of climate, substrate, organisms, relief, and time in differentiating urban from non-urban areas, and for determining heterogeneity within spatially extensive metropolitan areas. In addition to reviewing key findings relevant to each state factor, we note the emergence of tentative "urban syndromes" concerning soils, streams, wildlife and plants, and homogenization of certain ecosystem functions, such as soil organic carbon dynamics. We note the utility of the ecosystem approach, the human ecosystem framework, and watersheds as integrative tools to tie information about multiple state factors together. The organismal component of urban complexes includes the social organization of the human population, and we review key modes by which human populations within urban areas are differentiated, and how such differentiation affects environmentally relevant actions. Emerging syntheses in land change science and ecological urban design are also summarized. The multifaceted frameworks and the growing urban knowledge base do however identify some pressing research needs.  相似文献   
624.
The active management of air-filled cave systems is virtually non-existent within the karst landscape of west-central Florida. As in every karst landscape, caves are important because they contain a wide variety of resources (e.g., biota, speleothems) and can act as direct connections between surface and subsurface hydrological processes, potentially exacerbating the pollution of groundwater. Before sound management policies can be drafted, implemented, and enforced, stakeholders must first have knowledge of the management requirements of each cave. However, there is an informational disconnect between researchers, stakeholders, and the recreational caving community. Here, we present a cave inventory system that simplifies the dissemination of resource knowledge to stakeholders so that cave management and protection policies can be drafted and implemented at the state and local level. We inventoried 36 caves in west-central Florida, located on both public and private land, and analyzed cave resource data to provide insights on cave sensitivity and disturbance using two standardized indices. The data revealed that both public and private caves exhibit a wide range of sensitivity and disturbance, and before management strategies can be drafted, the ownership of each cave must be considered. Our inventory geodatabase serves as a link between researchers, landowners, and the public. To ensure the conservation and protection of caves, support from county or state government, combined with cave inventory data, is crucial in developing sound management policy.  相似文献   
625.
总结了肇庆市城镇、乡镇和农村饮用水水源地的调查情况,深入分析了影响各水源地水质情况的原因以及产生的影响,并此提出相应的环保建议和改善措施.  相似文献   
626.
从环保执法体制,环保执法法律,环保执法能力等方面简述了环保执法难的原因.指出应理顺环保执法体制,营造良好的执法制度环境.从环保执法的源头入手,完善环保立法.提高执法人员素质,加强执法技术装备,提高环保执法能力.突破现有的环保执法模式,按照可持续发展的现实需要,构建起政府控制与多种形式相结合的开放式的有效环保执法体制,从...  相似文献   
627.
简述了环境监测档案在环境保护、生态建设、社会经济发展中的重要价值,分析了当前四级环境监测档案管理中人员培养、信息化建设、保密管理等存在问题,提出,应完善档案管理设备,引进档案管理专业人才,落实档案管理职责,制定相关制度,加强档案密级管理,加快档案信息化建设.  相似文献   
628.
介绍浙江省及省会城市杭州的电磁辐射环境污染源概况。浙江省现有各类污染源9324个,总功率4242kW;高压线(缆)513条,总长11606km;变电站304座;无轨电车3条。杭州市有各类污染源4210个,总功率2366kW;高压线(缆)88条,长度1726km;变电站55座。分析了各类污染源的发展趋势。  相似文献   
629.
This article reports the results of an examination of the relationships between degree of sprawl and improvements in ozone air quality for 52 metropolitan areas in the US. It also examines state political alignment and environmental resources with regard to these two primary objects of investigation. Evidence of a relationship between sprawl and air quality improvement was identified, but the evidence is ambiguous. More research appears warranted to explore the sprawl–air quality improvement relationship. Electronic Publication  相似文献   
630.
在简单介绍工业废渣填埋场工程、运行管理、填埋废物情况的基础上,对渣场及周边环境状况进行分析,并对今后工作提出改进建议。  相似文献   
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