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991.
水污染问题的经济学分析及其对策探讨   总被引:2,自引:0,他引:2  
针对我国水资源污染的现状,从经济学角度对水污染的原因进行了分析,指出在公共资源产权没有明确界定的情况下,公共资源总是被过度利用,水资源产权制度缺损导致的外部性是水污染问题产生的根本原因;提出通过状态转移、实行产权管理、建立完善的市场调节机制和法律体系,是解决我国水污染问题的根本出路.  相似文献   
992.
ABSTRACT: The Hanging Gardens are a unique feature of Zion National Park. Knowledge of the source and residence time of water discharging from the Hanging Gardens is necessary to help preserve these features. Ground-water chemical and isotopic data distinguish the discharge from seeps and springs into two groups, one of low and one of high conductivity. Water with low conductivity likely originates as recharge near the seeps and springs, and it only interacts with the Navajo Sandstone. High conductivity water, on the other hand, originates as recharge on the tops of plateaus to the east, where it interacts with marine rocks of the Carmel Formation. Carbon dating of these ground waters indicates that the low conductivity water is essentially modern recharge, while the high conductivity water was recharged 1,000 to 4,000 years ago.  相似文献   
993.
Many state and local agencies have begun to adopt computer technology as a means of upgrading existing mapping and related practices. These agencies are faced with the dualism of wanting modern technology within a traditional setting and demanding technological independence at the same time. This article is an account of the art of technology transfers, with discussions about the necessary ingredients and constraints in the identification, adaptation, absorption, implementation, diffusion, and evaluation of new technologies. In general, a systematic approach towards the strengthening of endogenous capabilities with sufficient provision for operational and policy changes may be preferable to the idea of comprehensive planning.  相似文献   
994.
ABSTRACT: An input-output method, using a network of ideal continuous stirred-tank and plug-flow tublar reactors, is adopted to analyze residence time distribution data for a separated mechanical aeration system. The usefulness of this modeling concept is enhanced by its simplicity, especially in the presence of a first-order reaction. This facilitates use of the model format for wastewater quality prediction. Moreover, first-order rate constants can also be estimated from the model, if conversions due to the reaction rate are available.  相似文献   
995.
The general intervention model is applied to hydrologic and meteorologjc time series from the Canadian Arctic. The authors show how the model is able to account for environmental interventions, missing observations in the data, changes in data collection procedures, the effects of external inputs, as well as seasonality and autocorrelation. Methods for identifying transfer functions by making use of a physical understanding of the processes involved are demonstrated and sample applications of the general intervention model to Arctic data are shown.  相似文献   
996.
Air pollution from hazardous waste landfills and lagoons is largely unknown. Routine monitoring of toxic air contaminants associated with hazardous waste facilities is difficult and very costly. The method presented in this paper would be useful for air quality assessment in the absence of monitoring data. It may be used as a screening process to examine the question of whether or not volatilization is considered to be significant for a given contaminant and also to evaluate permit applications for new hazardous waste facilities concerning waste volatilization problems.  相似文献   
997.
生态综合补偿的提出表明国家对生态补偿关注的重点从资金的来源转向资金使用的效果,其中转移支付法制是影响生态综合补偿效果的主要变量。从中央和地方两个层面的立法来看,贫困地区生态补偿转移支付立法从维护公平正义提供倾斜性补偿资金,转向促进“绿色发展”“绿色减贫”的生态补偿整体性效益建设。然而,整体上,相关法制建设尚显不足,如贫困地区利益未充分表达、补偿资金使用自主权未能充分发挥、整体性监督考核机制不健全等。原因在于,扶贫政治思维淡化了贫困地区生态综合补偿法律制度的属性,覆盖面难以普及;不同利益诉求造就了贫困地区生态综合补偿转移支付制度约束;行政放权的非制度化影响贫困地区生态补偿转移支付整体性效益。应以实现可持续的自我发展权新理念加强贫困地区生态综合补偿转移支付的法律制度化建设,明晰贫困地区生态综合补偿中转移支付的重要地位,夯实基础性财权,同时构建适应生态综合补偿的整体性考核机制。  相似文献   
998.
ABSTRACT. The Heat Storage Well concept evolved at TEMPO in 1972. Technical, economic, institutional, and legal aspects of implementing the concept are being studied. Heat Storage Wells offer the possibility of conserving a substantial part of the heat energy now wasted in generating electricity and of reducing thermal pollution caused by the waste heat. Large thermal electric power plants would produce heat at useful temperatures such as 300–400°F. Combined electric- and heat-generating systems will require low-cost, low-loss storage of large amounts of hot water for periods of 90 to 180 days to serve both electric loads and seasonally-varying heat loads. Compared to conventional electricity-only systems, combined electricity-heat systems can save more than 20 percent in energy, reduce the cost of both electricity and heat, and eliminate the need for cooling water or towers. Possibilities for changes in legal and institutional practices are suggested, such as making resource-allocation decisions on the basis of energy units rather than dollars.  相似文献   
999.
ABSTRACT: A user-oriented research plan is presented herein. Its principal components are: (1) a mechanism for identifying social goals and translating them into research objectives; (2) procedures for setting priorities; (3) a program planning technique for designing projects to impact on important research objectives; (4) a mechanism for coordinating research activities of important research producers; (5) a structure for encouraging and establishing interdisciplinary team efforts when they are required; (6) a well-coordinated technology transfer plan; and (7) an effective method for promoting and sustaining user-researcher cooperation. Both basic and applied research designs are examined and criteria presented. The implementation of research plans is also discussed and various factors which play a role in implementation are outlined including: coordination, goal interpretation and priority setting, project Planning, Project review, interdisciplinary considerations and the user-researcher interface.  相似文献   
1000.
随着分子生物学的发展,16S rRNA基因技术被逐渐应用到环境科学领域中。目前在环境保护和治理中,该技术主要被用于鉴定污染物的生物降解菌和分析环境样品中的微生物群落多样性,由于它不必将微生物培养分离出来,也就避免了在培养过程中可能出现的微生物去失的情况。本文对16S rRNA基因技术及其在环境科学领域中的应用现状和发展作了一简要介绍,并对16S rRNA基因技术存在的不足进行了讨论。  相似文献   
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