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人工湿地的生态休闲利用与设计 总被引:4,自引:0,他引:4
人工湿地系统除了可以起到净化污水的作用,在经过精心设计后,还可发挥与自然湿地系统同样的生态保护功能,更可为人们提供一个休闲娱乐、旅游观光、科教科研的场所,越来越多的人工湿地系统开始重视并采用一系列的设计手段以充分发挥其自然价值和社会价值。本文详细地介绍了目前人工湿地综合利用研究进展,分析了综合利用时一些潜在的问题,及其设计时应当加以考虑的注意事项和建议。 相似文献
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J. Jeffrey Peirce 《Journal of the American Water Resources Association》1980,16(2):220-225
ABSTRACT: Strategies for controlling nonpoint sources of water pollution are discussed in terms of three representative states and eighteen regional agencies. The programs in Virginia, New York, and Wisconsin are seen to exhibit control options which range from voluntary action to strict regulation. Four conclusions are drawn from the analysis. First, nonpoint sources of pollution are a major component of the overall water pollution problem in the three states. Second, technical controls are generally available to solve the problems. Third, existing controls programs are not necessarily technologically sound or cost effective. Finally, existing control programs are capable of instituting solutions to the problems if and only if specified actions take place within the respective states and regions in the future. Critical research needs are identified which will assist states and regions in developing cost effective programs to control nonpoint source pollution. 相似文献
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本文在阐明雷暴形成的背景条件的基础上,提供了全球雷暴的分布特征,分析其对环境造成的严重危害,并着重分析雷电在雷暴中的形成及其危害.最后简略介绍防雷电技术近30年来的进展. 相似文献
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Carl F. Cerco 《Journal of the American Water Resources Association》1988,24(2):255-260
ABSTRACT: Sediment-water exchanges of ammonium, nitrate, and phosphate are incorporated into a eutrophication model of Gunston Cove, Virginia. The exchange rates are obtained from laboratory measurements and are modeled as empirical functions of temperature, concentration, and pH. Simulation of the period from June 1 to September 30, 1983, indicates nitrogen, phosphorus, and chlorophyll ‘a’ are correctly modeled only when the sediment-water nutrient exchanges are taken into account. 相似文献
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乌鲁木齐声环境功能区可分为四类,通过对这些有代表性的噪声监测点进行长期定点监测,了解各类功能区声环境质量特征及受污染情况。通过对近3 a四类声环境功能区的噪声昼间、夜间连续等效声级及污染情况的统计分析,掌握乌鲁木齐市噪声污染状况,研究治理对策。 相似文献
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Helen Ingram 《Journal of the American Water Resources Association》1972,8(6):1177-1188
A set of decision rules have governed the traditional politics of water development. This paper identifies these rules, describes their operation, and explains the logic behind their adoption. Personal interviews with a large number of decision makers are cited to substantiate and illustrate particular rules. There are five decision rules: local support, agreement, mutual accommodation, mutual noninterference, and fairness and equity. These guidelines are intended to insure support, lessen conflict, and protect the reputation of water development as a worthwhile federal investment. Since there are current indications that the traditional decision rules are no longer followed, the paper aims to identify why and how the rules are changing. 相似文献
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D. Rayfield J.W.S. Longhurst P.S. Ramsden J.A. Dinsdale R.M. Elliott D.E. Conlan 《The Environmentalist》1998,18(1):3-13
The transport-induced air quality problems of the Greater Manchester region are examined. The problems are defined in terms of economic and social factors leading to the development of a car-based economy. The impacts of transport emissions on the natural and built environment and human health are discussed. The administrative, legislative and pollution control responses to the problem are examined. The nature of future air quality problems will require an integration of traffic management, land use, public transport and pollution control policies if they are to be satisfactorily addressed. A series of policy recommendations towards this end are included. 相似文献
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Integrated environmental management and environmental awareness in South Africa: where are we going?
A. M. Avis 《Journal of Environmental Planning and Management》1994,37(2):227-242
The objectives, principles and importance of Integrated Environmental Management (IEM) are briefly discussed. The problems associated with a first world procedure in South Africa (a third world country), and the roles various groups play is related to the game of chess. Government authorities (King) are responsible for legislating the rules of the game, which are inadequate. The developers (Rooks) are concerned with economic growth but also wish to be appraised of environmental issues, but the lack of legislation results in confusion. The environmental pressure groups are Bishops with uncompromising and myopic views, and often do not represent all sectors of the public (Pawns), particularly African blacks whose view of the environment has been adversely affected by apartheid. The media are ‘Super‐pawns’, their attitude towards the environment depends on what the public want to hear, and they are dependent on the other players for their survival. The environmental consultants are Knights expected to solve the environmental problems associated with complex projects. It is concluded that, at present, the environmental chess game in South Africa will end in stalemate, unless adequate legislation and clearly defined guidelines are produced. 相似文献
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Thomas M. Walski 《Journal of the American Water Resources Association》1983,19(3):489-498
Savings in capital, operation, and maintenance costs of new water supply facilities are referred to as “long run foregone costs.” Any conservation measure leads to reduction of water use or loss, however, significant long run foregone costs are realized only when reductions in size or delays in construction of facilities result. In order to accurately evaluate these costs it is necessary to know which facilities are affected and how they are affected (i.e., eliminated, downsized, or delayed). The effects of several levels of conservation on long run fore gone costs for an actual study are presented and some easy to use equations that may be used to calculate such savings are then derived. Some rules are presented to determine if it is more economical to delay construction or downsize facilities. 相似文献
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Robert B. Wenger Charles R. Rhyner Edith E. Wagoner 《Resources, Conservation and Recycling》1997,20(4):267-276
Some states measure progress in their waste reduction programs on the basis of recycling rates, while others use disposal-based reduction rates. It is generally recognized that these two measures are conceptually distinct. Nevertheless, when informational surveys of waste reduction activities are compiled, the data are usually combined in a manner that blurs this distinction and complicates the issues involved. In this paper, these two concepts are defined in a precise manner and equations are derived which clearly depict the relationship between recycling rates and disposal-based reduction rates. Information from a national survey and the US Environmental Protection Agency is used to illustrate the concepts which are developed in the paper. 相似文献
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Victor Rodriguez Padilla 《Natural resources forum》1991,15(1):2-14
The petroleum tax systems of nine West African countries are compared and analysed for their effectiveness in capturing the maximum amount of oil revenues. As a general rule, those countries which are major oil-exporting countries have the highest tax rates whereas those which are oil-importing countries have the lowest. The tax systems have changed over time, reflecting inter alia, changing national attitudes towards foreign investment, the price of oil and domestic needs. One conclusion reached is that many of the tax systems in place today are regressive in that the tax rates are fixed and are not adjusted to the profitability or non-profitability of the oil field . 相似文献
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Ed. McKenzie 《Journal of the American Water Resources Association》1985,21(4):645-650
ABSTRACT: Simple models are presented for use in the modeling and generation of sequences of dependent discrete random variables. The models are essentially Markov Chains, but are structurally autoregressions, and so depend on only a few parameters. The marginal distribution is an intrinsic component in the specification of each model, and the Poisson, Geometric, Negative Binomial and Binomial distributions are considered. Details are also given for the introduction of time-dependence into the means of the sequences so that seaonality can be treated simply. 相似文献
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Renewable and hybrid energy systems (HESs) are expanding due to environmental concerns of climate change, air pollution, and depleting fossil fuels. Moreover, HESs can be cost effective in comparison with conventional power plants. This article reviews current methods for designing optimal HESs. The survey shows these systems are often developed on a medium scale in remote areas and stand-alone, but there is a global growing interest for larger scale deployments that are grid connected. Examples of HESs are PV–wind–battery and PV–diesel–battery. PV and wind energy sources are the most widely adopted. Diesel and batteries are often used but hydrogen is increasing as a clean energy carrier. The design of an efficient HES is challenging because HES models are nonlinear, non-convex, and composed of mixed-type variables that cannot be solved by traditional optimization methods. Alternatively, two types of approaches are typically used for designing optimal HESs: simulation-based optimization and metaheuristic optimization methods. Simulation-based optimization methods are limited in view of human intervention that makes them tedious, time consuming, and error prone. Metaheuristics are more efficient because they can handle automatically a range of complexities. In particular, multi-objective optimization (MOO) metaheuristics are the most appropriate for optimal HES because HES models involve multiple objectives at the same time such as cost, performance, supply/demand management, grid limitations, and so forth. This article shows that the energy research community has not fully utilized state-of-the-art MOO metaheuristics. More recent MOO metaheuristics could be used such as robust optimization and interactive optimization. 相似文献
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Various governmental regulatory agencies are responsible for establishing regulations on the discharge of chlorinated organic
compounds from pulp and paper mills. The procedures for setting permit limits are the basic topic of this article. Different
methods of determining permit limits are set forth and discussed in a number of references, including documents of the Environmental
Protection Agency. This paper discusses in detail the application of one particular methodology—the lognormal model approach.
In this paper we utilize a real data set and include the necessary calculations required to set up permit limits.
The basic tenets of the permit process are such that if limits are set too low, operators who are in full regulatory compliance
will still be frequently cited, and if limits are set too high, operators who are not in compliance will seldom if ever be
cited. Thus there is a great need for these effluent limits to be determined with great care, both to protect the environment
receiving the wastewater and the industry producing the wastewater. 相似文献
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Subhes C Bhattacharyya 《Natural resources forum》1995,19(2):135-142
The removal of energy subsidies is considered to be the first step towards a better environment. In order to pursue a policy for subsidy removal, one needs to know exactly the amount of subsidies accorded to different fuels. In this paper, the subsidies involved in the coal sector in India are estimated. Existing prices are reviewed, economic prices are estimated and the two are compared to arrive at appropriate subsidies or taxes. The subsidies are also distributed among different sectors and policy implications of subsidy removal are discussed. Finally, the need to have a larger data sample to study the coal industry is stressed, in order to better understand the cost structure . 相似文献
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湖南邵东县黄花菜资源的开发研究 总被引:3,自引:0,他引:3
本文分析了湖南省邵东县黄花菜生产的优良生态条件和社会经济条件,指出了生产与经营上的缺陷,揭示了进一步开发的潜力及广阔的营销前景,提出了合理开发的建议。 相似文献