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521.
522.
This paper considers a pollution economics and control problem which uses a queuing framework. This approach is shown to establish a link between a firms economic activity and its linkages to externalities such as pollution, environmental control (as would be considered by an environmental agency) and a number of variables commonly encountered in such problems. A number of environmental issues are addressed and a Stackleberg game is formulated between the environmental regulating agency and polluting firms where the firm is assumed to be a follower, maximizing its profits while the environmental agency is a leader, assumed to be a long run average cost manager. The solution we propose is based on the agencys internalizing externalities at firms expense using both subsidies for pollution abatement and penalties. In this framework, environmental costs penalties, incentive for pollution abatement investment and the sampling probabilities of environmental controls are determined. 相似文献
523.
中国泥石流形成环境剖析 总被引:2,自引:0,他引:2
丰富的松散固体物质、充沛的水源和陡峻的地形,作为泥石流形成的三个基本条件,已得到学者们的认同。就本质而言,这三者可归纳为能量和物质两大因素。本文从中国泥石流区域分布着眼,从不同尺度的自然环境因素和人为活动,探讨中国泥石流形成发展的基本规律。研究结果表明,大尺度的区域地质背景、大地貌单元和犬气候系统是控制泥石流形成发育的主导因素;不稳定斜坡因子、小尺度水文气象因子、流域形态因子、森林植被因子等,在大尺度因素的基础上,对泥石流的形成有重要影响;历史上,特别是近期人类经济活动对环境的不良影响,加剧了泥石流的发展。泥石流灾害非单一因子所致,而是诸多因子综合作用的结果,是山地环境退化的产物。泥石流活动具有开放性、内外营力作用的共同性以及自然因素和人为因素的复合性这三大特点。 相似文献
524.
王建忠 《沙漠与绿洲气象(新疆气象)》2005,28(1):24-26
应用计算机多媒体技术建立的《新疆地理环境》,包括新疆境内气候概况、水文、地貌、植被及交通等内容,它将图形、图像、文字、声音、视频、动画等媒体元素集于一身,实现人机的最佳结合,为有关部门和气象业务人员提供一个多角度、多方位的辅助查询平台。 相似文献
525.
中甸晚三叠世图姆沟组岩石化学与构造环境 总被引:9,自引:0,他引:9
本文对中甸东部晚三叠世图姆沟组深水浊积岩和弧火山岩、微量和稀土元素进行研究,投点多落入再旋回造山带物源区;微量和稀土元素与图解中多接近大陆岛弧区;常量元素分析与相关图解接近活动大陆边缘和大陆岛弧环境,与火山岩的大地构造环境具有相同的结论。图姆沟组为甘孜—理塘洋盆向西俯冲消减,中甸褶皱带东缘由被动大陆边缘转化为活动大陆边缘过程中形成的岛弧火山—沉积岩系。 相似文献
526.
This paper describes 11 microfacies types in late Bathonian–Early Callovian carbonates of the Kuldhar Member of the Jaisalmer Formation (Rajasthan) and the Keera Golden Oolite Member of the Chari Formation (Kachchh Mainland) western India. The different microfacies associations reported in this study reflect an ideal shallowing upward sequence, representing a system of bioclastic bars developed on the lower ramp, evolving into an oolitic bar-to-bank system separating restricted lagoonal—from lower ramp environment. Four main types of cements, i.e. bladed, fibrous, syntaxial overgrowth and blocky cement (characterized in a few cases by ferroan calcite and anhydrite II) occur in these carbonates. The study also reveals that chemical compaction followed the two phases of early mechanical compaction that largely governed porosity of these limestones. However, micritization and neomorphism also contributed significantly in this respect. Diagenetic signatures in these carbonates suggest that marine phreatic and fresh water phreatic environments dominated, but deep burial diagenesis also played its role in shaping these rocks. The early and late diagenetic changes have been controlled by the depositional facies evolving in a basin riddled with rifting in an extensional tectonic regime forcing regional-scale sea level fluctuations. 相似文献
527.
Stephanie Pincetl 《Geoforum》2006,37(2):246-255
The United States is often considered the progenitor of conservation planning in the world, the first to establish a vast public domain, for example. But with continued population growth, conservation planning on private lands—rural and at the urban fringe—continues to be a substantial challenge due to a tradition of local home rule in land use planning and strong private property protection afforded by the US Constitution. New “bottom-up” collaborative approaches, as well as other innovative strategies seem to be emerging. How effective these will be given pressures for growth and high property values remain to be seen without a rethinking of ideas of nature, a rebalancing of the role of property in American local fiscal regimes, and of private property rights. 相似文献
528.
Climate change impacts threaten existing development efforts and achieving future sustainability goals. To build resilience and societal preparedness towards climate change, integration of adaptation into development is being increasingly emphasized. To date, much of the adaptation literature has been theoretical, reflecting the absence of empirical data from activities on the ground. However, the Funds established under the United Nations Framework Convention on Climate Change and managed by the Global Environment Facility, the Least Developed Countries Fund, the Special Climate Change Fund and the Strategic Priority for Adaptation, have approved financing for 133 adaptation projects in 70 countries with sufficient documented experience to allow for initial categorization and evaluation. This article provides the first substantial compendium of adaptation actions identified through the allocation and disbursement of these Funds and organizes these actions into a generalized typology of adaptation activities. The information obtained sheds new insight into what adaptation is, in practice, and suggests some next steps to strengthen the empirical database. Ten types of overarching adaptation activities were identified through an analysis of 92 projects financed through these Funds. This paper analyzes these adaptation activities and compares them with theoretical constructs of adaptation typologies. We find that many of the early ideas and concepts advanced by theoreticians are consistent with results from the field. The adaptation categories that recur the most in Global Environment Facility projects are enabling and relatively inexpensive measures, such as those related to capacity building, policy reform, and planning and management. However, a rich panoply of technical actions ranging from information and communications technology, to early warning systems, to new or improved infrastructure, are also identified as common project goals. Future refinements of the costs of various adaptation actions, the mixture of technical and management options, and evaluating the efficacy of actions implemented, will be key to informing the future global adaptation agenda. 相似文献
529.
Groundwater is the main source of water supply for Beijing. Through analysis of the water resources in Beijing from 1980s up to now, this paper finds the major problems in the exploitation and utilization of groundwater in Beijing lie in the over-exploitation and pollution in groundwater, which are primarily caused by the rapid growth of population, enduring imbalance between exploitation and replenishing of groundwater and the contamination of groundwater. Thus based on this, this paper puts forward proposals and opinions to exploit groundwater in a scientific and moderate way, and to comprehensively protect the ground?water resources and environment in Beijing. 相似文献
530.
“3S”技术支持下的考古探测方法研究述评 总被引:3,自引:0,他引:3
从“3S”技术在考古研究中的最新进展出发,详细讨论了GPS、RS和GIS在当前考古工作中的应用现状、研究热点和发展趋势
。在此基础上,提出了“3S”技术支持下的考古综合探测体系,强调了多源异构数据在考古研究中的中心作用。整个研究框架严格
考虑了相关尺度对模型建立的约束作用,提供了一个具备较强普适性和伸缩性的环境考古工作方案。 相似文献