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801.
针对当前严重的水污染问题,采用博弈论对突发性水污染事件治污决策进行了研究,为事件应急管理提供理论支撑与决策支持。基于经典博弈论构建了信息不对称下突发性水污染事件中管理部门与企业之间的信号博弈模型,对信号发送方企业的类型空间、信号空间和信号接收方管理部门的行动空间进行假设,求得了模型的精炼贝叶斯均衡解,并对不同参数取值下的均衡解进行了分析。基于有限理性建立了企业群治污决策进化博弈模型,通过求解模型复制动态方程得到了不同参数取值下的进化稳定策略,并对模型进化趋势进行了分析。结果表明:对突发性水污染事件进行治污决策时,通过公开企业信息与信誉,提高对企业是否采取治污策略的奖惩力度,采用现代先进信息技术降低企业治污与管理部门检查的成本等方式有助于企业采取治污策略。  相似文献   
802.
Because there is no specific legislative or regulatory guidance, there is no "right" way to allocate liability at Superfund sites. Allocation based on the cost of a remedy, and allocation based on the need for a remedy, i.e. risk-based allocation, represent two possibilities. Other allocation schemes can be located between these two philosophical poles. When waste streams and environmental impacts are qualitatively similar, allocation based solely on costs may make the most sense. When one or more potentially responsible parties (PRPs) have qualitatively different wastes or impacts, an allocation scheme based on both contribution to cost and to risk may be able to incorporate all PRPs. In any case, dissident PRPs, whose contribution to remedy costs is large but whose contribution to risk is small, may find satisfaction in the courts where there is precedent for risk-based allocation.  相似文献   
803.
Yang G  Ma L  Xu D  Li J  He T  Liu L  Jia H  Zhang Y  Chen Y  Chai Z 《Chemosphere》2012,87(8):845-850
Arsenic levels and speciation in the total suspended particles (TSPs) were quantitatively determined by high performance liquid chromatography on-line coupled with hydride generation atomic fluorescence spectrometry in Beijing, China from February 2009 to March 2011. The high TSP levels fluctuated between 0.07 and 0.79 mg m−3, with a mean level of 0.32 ± 0.17 mg m−3. The total arsenic concentrations ranged from 0.03 to 0.31 μg m−3 (mean: 0.13 ± 0.06 μg m−3) in Beijing‘s air. The concentrations of As(III) and As(V) ranged from 0.73 to 20 ng m−3 (mean: 4.7 ± 3.6 ng m−3) and from 14 to 2.5 × 102 ng m−3 (mean: 67 ± 35 ng m−3), respectively. As levels and speciation demonstrated relative higher levels in spring and autumn and lower values in summer and winter. As(V) accounted for 81-99% of the extractable species in the TSP samples which showed that As(V) was the major fraction of the extractable As. Organoarsenic species, monomethylarsonate (MMA) and dimethylarsinate (DMA) were not found in all samples. Higher values of enrichment factors demonstrated that arsenic in TSP mainly come from anthropogenic sources. High As and its species levels in air and respiratory exposure (0.30-0.84 μg d−1) attributed to higher excess cancer risk ((4.2 ± 2.0) × 10−4) for people in Beijing.  相似文献   
804.
结合秦皇岛市沿海旅游城市的实际情况,指出了环境应急管理中存在的机构不健全、人员不固定、设备和经费缺乏等问题,并从队伍、装备、预案、演习、应急指挥、危险化学品运输等10个方面提出了对策,以期为环境应急管理工作提供参考。  相似文献   
805.
区域用水结构演变规律与调控对策研究   总被引:1,自引:0,他引:1  
我国水资源严重短缺,在新的形势下,必须根据经济发展调整用水结构.本文以地处西北干旱区的榆林市为例,通过收集榆林市1990-2005年国民经济各行业用水量,结合信息熵原理,计算出不同年份用水量熵值及优势度动态演化情况.结果表明,榆林市用水系统熵值由1990年的0.569增加到2005年的0.667,总体呈上升趋势,表明榆林市用水结构趋向无序.同时,系统的均衡度也呈增加趋势,这表明当地用水系统在趋于无序发展的同时,用水系统的均衡程度有所提高,系统均衡性增强.从地区来看,南六县的用水系统熵值要高于北六县,且南六县用水系统熵值一直处于下降趋势,北六县则在波动中表现出一定的上升趋势,这与南六县长期从事特色农业,产业结构相对比较稳定,而北六县主要发展工业,导致用水结构中农业、工业、生活用水结构变化较大有关.最后,结合榆林市实际,提出"南护水源,北抑需求"的总体调控思路,通过建立权威、高效、协调的管理机制,推进水管理体制改革、加强立法和执法监督,规范水资源管理行为、因地制宜,调整和优化产业结构, 大力发展生态型低耗水产业、明确水权、建立水市场,制定合理水价、广泛宣传,积极引导,改变用水观念等措施,不断调整用水结构,最终实现经济社会可持续发展.  相似文献   
806.
Rodin J 《Ambio》2011,40(2):221-230
Between 1985 and 1995, fertility in Eastern Europe declined from 2.2 children per woman to merely 1.5 on region-average. Previous research has emphasized mainly the economic turmoil during transition or the influx of new ideas regarding fertility and family relations. This article suggests that applying a risk management perspective on fertility patterns may put additional light on the reasons behind the fertility decline in post-communist Europe. The complexity of modern social systems has made people increasingly dependent on the state for risk evaluation and risk management. The article formulates the hypothesis that transition itself disrupted the mental models that helped people to navigate among the risks associated to having and raising children. Left to their own devices, women in Eastern Europe became more inclined to postpone childbirth or discard this option altogether.  相似文献   
807.
Renn O  Klinke A  van Asselt M 《Ambio》2011,40(2):231-246
The term governance describes the multitude of actors and processes that lead to collectively binding decisions. The term risk governance translates the core principles of governance to the context of risk-related policy making. We aim to delineate some basic lessons from the insights of the other articles in this special issue for our understanding of risk governance. Risk governance provides a conceptual as well as normative basis for how to cope with uncertain, complex and/or ambiguous risks. We propose to synthesize the breadth of the articles in this special issue by suggesting some changes to the risk governance framework proposed by the International Risk Governance Council (IRGC) and adding some insights to its analytical and normative implications.  相似文献   
808.
Plant Protection Products can affect soil organisms and thus might have negative impacts on soil functions. Little research has been performed on their impact on tropical soils. Therefore, the effects of the insecticide lambda-Cyhalothrin on earthworms were evaluated in acute and chronic laboratory tests modified for tropical conditions, i.e. at selected temperatures (20 and 28 °C) and with two strains (temperate and tropical) of the compost worm Eisenia fetida. The insecticide was spiked in two natural soils, in OECD artificial soil and a newly developed tropical artificial soil. The effects of lambda-Cyhalothrin did rarely vary in the same soil at tropical (LC50: 68.5-229 mg a.i./kg dry weight (DW); EC50: 54.2-60.2 mg a.i./kg DW) and temperate (LC50: 99.8-140 mg a.i./kg DW; EC50: 37.4-44.5 mg a.i./kg DW) temperatures. In tests with tropical soils and high temperature, effect values differed by up to a factor of ten.  相似文献   
809.
Polychlorinated-dibenzo-p-dioxins and -dibenzofurans (PCDD/Fs) were measured in soils and sediments from the Yellow Sea region. Korean soils and sediments mostly contained detectable PCDD/Fs and showed a widespread distribution among locations. Soil and sedimentary PCDD/Fs from China were comparable to or less than those in Korea. The patterns of relative concentrations of individual congeners in soils were different between the two countries, but similar in sediments. Sources of PCDD/Fs in China and Korea were found to be independent of each other and their distributions reflected matrix-dependent accumulation. Spatial distribution indicated some point sources in Korea while Chinese sources were more widespread and diffuse. PCDD/Fs measured in the coastal areas of the Yellow Sea were comparable to or less than those previously reported in for eastern Asia. However, ∑TEQs in soils and sediments were near to or, in some cases exceeded environmental quality guidelines.  相似文献   
810.
We reviewed the published evidence of lead (Pb) contamination of urban soils, soil Pb risk to children through hand-to-mouth activity, reduction of soil Pb bioavailability due to soil amendments, and methods to assess bioaccessibility which correlate with bioavailability of soil Pb. Feeding tests have shown that urban soils may have much lower Pb bioavailability than previously assumed. Hence bioavailability of soil Pb is the important measure for protection of public health, not total soil Pb. Chemical extraction tests (Pb bioaccessibility) have been developed which are well correlated with the results of bioavailability tests; application of these tests can save money and time compared with feeding tests. Recent findings have revealed that fractional bioaccessibility (bioaccessible compared to total) of Pb in urban soils is only 5-10% of total soil Pb, far lower than the 60% as bioavailable as food-Pb presumed by U.S.-EPA (30% absolute bioavailability used in IEUBK model).  相似文献   
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