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201.
We investigate the effect of domestic politics on international environmental policy by incorporating into a classic stage game of coalition formation the phenomenon of lobbying by special-interest groups. In doing so, we contribute to the theory of international environmental agreements, which has overwhelmingly assumed that governments make decisions based on a single set of public-interest motivations. Our results suggest that lobbying on emissions may affect the size of the stable coalition in counterintuitive ways. In particular, a powerful business lobby may increase the government's incentives to sign an agreement, by providing it with strong bargaining power with respect to that lobby at the emission stage. This would result in lower total emissions when the number of countries involved is not too large. We also show that things change radically when lobbying bears directly on the membership decisions, suggesting that both the object and timing of lobbying matter for the way in which membership decisions, emissions and welfare are affected.  相似文献   
202.
Can environmental provisions in preferential trade agreements (PTAs) foster an environmental race to the top? The ways in which different enforcement mechanisms in North–South PTAs affect the implementation of environmental standards in developing countries are examined. It is argued that environmental provisions in European Union (EU) and United States (US) PTAs will be effective in instigating policy change in partner countries, although the timing of the effect will vary significantly. Fines and sanctions in US PTAs incentivize partner countries to reform during the negotiation process. Reform in EU PTA partners is predicted to occur during agreement implementation as a result of the EU’s policy dialogue approach. Illustrative evidence is provided and the hypotheses are tested using statistical estimations of EU and US PTAs with environmental provisions on developing countries’ environmental policy reform.  相似文献   
203.
Jan Karlas 《环境政策》2017,26(5):825-846
Why do some states and state coalitions, acting within the United Nations Framework Convention on Climate Change (UNFCCC), support harder legalization of the global climate regime? In order to explain why, the effects of four causal factors are considered: climate vulnerability, the emission intensity of the national economy, a state’s power position, and socialization into climate norms. To identify the legalization positions of UNFCCC actors, an original content analysis is conducted of all the submission and meeting statements made at the Ad Hoc Working Group on the Durban Platform during the years 2012–2015. Subsequently, a qualitative comparative analysis is carried out to find out which combinations of the causal factors offer a sufficient explanation for the analyzed outcome, leading to the identification of two causal pathways that lead states to endorse harder legalization of the climate regime.  相似文献   
204.
Phosphorus (P) is a limiting nutrient in freshwater systems and when present in runoff from agricultural lands or urban centers may contribute to excessive periphyton growth. In this study, we examined the link between soil erosion and delivery of eroded soil to streams during flow events, and the impact of that freshly deposited soil on dissolved reactive P (DRP) concentrations and periphyton growth under baseflow conditions when the risk of stream eutrophication is greatest. A microcosm experiment was designed to simulate the release of P from soil which had been amended with different amounts of P fertilizer to overlying water during baseflow conditions. Unglazed tiles, inoculated for five days in a second order stream, were incubated for seven days in microcosms containing soil with eight levels of soil Mehlich‐3 plant available phosphorus (M3P) ranging from 20 to 679 mg/kg M3P. Microcosm DRP was monitored. Following incubation tiles were scraped and the periphyton analyzed for chlorophyll a. Microcosm DRP concentrations increased with increasing soil M3P and equilibrium phosphorus concentration (EPC0). Relationships between M3P, EPC0, and DRP were nonlinear and increases in soil M3P and/or DRP had a greater impact on biomass accumulation when these parameters were above threshold values of 30 mg/kg M3P and 0.125 mg/L DRP. Significantly, this ecological threshold corresponds to the agronomic thresholds above which increased soil M3P does not increase plant response.  相似文献   
205.
Two prevalent views are reviewed on China's urbanization firstly. Then, this article highlights the characteristics and pattern of urbanization in the world based on the quadrants map, using data of 118 countries or areas. The results indicate that the process of urbanization in the world excluding the data of China has slowed down gradually. A further exploration examines China's urbanization process and economic development over time, which reveals that both urbanization level and the level of economic development belong to the low-grade coordination pattern. The low level of urbanization is closely connected with the low level of economic development. Actually, China's urbanization gap appeared during 1985-1995, but it has been eliminating this urbanization gap since 1995 as a result of rapid urbanization growing. The complicated realities revealed in this analysis challenge the existing two prevalent views.  相似文献   
206.
中国国际河流水资源利用立法略论   总被引:1,自引:0,他引:1  
我国的国际河流数量众多,分布广泛。国际河流的利用主要分为国际河流的航行利用和国际河流的水资源利用2个方面。我国对国际河流的利用主要表现为对国际河流水资源的利用。完善我国国际河流水资源利用立法非常重要。它可以确保我国既充分、合理,又合法、有据地利用国际河流水资源,消除国际舆论中“中国水威胁论”的不良影响;缓解国内水资源日益紧张的局面;发展流域经济;保护当地生态环境。运用综合分析和实证研究的方法,对我国国际河流水资源利用立法情况和对外谈判进行探讨。检视我国国际河流水资源利用立法存在诸多问题。国际河流水资源利用立法理念不协调;国际河流水资源污染防治立法视野狭隘;双边或多边区域性专项水协定缺失等问题表现得尤为突出。应采取调整国际河流水资源利用立法理念;坚持“公平利用”原则,维护我国权益;健全双边或多边的区域性专项水协定体系;拓宽立法视野,兼顾国际河流水资源利用和保育;保护国际河流水环境等措施,规制国际河流水资源的利用。  相似文献   
207.
淡水鱼脑AChE的动力学特性及抗抑制性   总被引:6,自引:1,他引:6       下载免费PDF全文
用PEG2000双水相萃取、DEAE-Sephadex A-50和SephadexG-200方法分离提纯麦穗鱼(Pseudorasbora parva)、金鱼(Carassius auratus)和虹鳟鱼(Salmo gairdneri)脑乙酰胆碱酯酶(AChE),比较这3种淡水鱼脑AChE纯酶液与粗酶液的动力学特性、抗抑制性及其种类之间的差异.结果表明,这3种鱼脑AChE的性质在种类间的差异要远远小于其在粗酶状态时酶活性的差异,由此得出AChE性质在种类间的差异并非影响这3种淡水鱼脑AChE活性差异的主要因素;由AChE抗抑制试验结果可知,这3种鱼脑AChE粗酶液对经溴水氧化后的马拉硫磷和三唑硫磷的敏感性及种间的差异都远大于纯酶液.  相似文献   
208.
基于淡水资源账户和污染账户的生态足迹改进模型   总被引:7,自引:0,他引:7  
论文通过增加淡水资源账户和污染账户,对通用的生态足迹模型进行改进,弥补了生态足迹模型中对淡水资源和对生态系统消纳污染物描述的不足,增强了生态足迹模型计测的准确性;同时以实际土地平均生产力法对东江流域涉及地市赣州、 梅州、 河源、 韶关、 惠州、 广州、 东莞和深圳等城市2008年的产量因子进行调整,计算了东江流域涉及8市2008年的生态足迹。结果表明:①2008年东江流域涉及各市的生态足迹和生态承载力差异较大,意味着各市之间的社会经济状况和资源禀赋大不相同。总的人均生态足迹的空间分布为除惠州和深圳外,有由上游至中下游增加的趋势;除淡水外的可利用人均生态承载力的空间分布,则呈现由上游至中下游减少的趋势。②生态足迹的空间变化随人均GDP和/或城镇人口比例的增加呈先增加后减少的趋势,这一结论或许能给流域内外的其他城市就如何减少乃至消除区域生态赤字提供一点启示,指出其经济社会发展的道路和下一步应该努力的方向。③各市除淡水外的总生态足迹均大于其生态承载力,因而整个流域不同程度地均存在生态赤字,即按照当前状况,这些地区都需要继续从区域以外的地方输入自然产品和资源及能源才能维持正常的发展。  相似文献   
209.
关于国际河流生态环境安全的思考   总被引:2,自引:0,他引:2  
生态环境安全是当今国际社会关注的热点,而国际河流流域的水资源保护与生态环境安全又是这一热点中的敏感点.本文结合中国与有关国家的国际河流的实际,分析了国际河流流域水资源保护与生态环境安全的有关问题、产生的原因与后果及其相互关系,指出维护生态环境安全存在的特殊问题,并提出了对策与建议.  相似文献   
210.
利用超声波提取-气质联用法调查了北京市不同水产品市场4种常见淡水食用鱼体内25种农药的残留水平,并利用商值法评价了农药的潜在健康风险.在采集的48个样品中,除七氯、o,p’-DDT、敌敌畏、对硫磷、毒死蜱、仲丁威和久效磷以外,其余18种农药均有不同程度检出.其中,检出率最高的为乙草胺(97.9%)和β-六六六(93.8%);检出农药含量最高的为百菌清(1 779.4μg·kg-1),其次为溴氰菊酯(620.3μg·kg-1).鱼体中有2~10种农药共存,其总浓度为2.7~1 932μg·kg-1.潜在健康风险评价结果表明,按照北京市民的平均水产品消费量,北京水产品市场上的4种主要食用鱼中的农药风险商值为0.043 43,处于较低水平.  相似文献   
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