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71.
In Germany, a county-resolution data set that consists of 35 land-use and animal-stock categories has been used extensively to assess the impact of agriculture on the environment. However, because such environmental effects as emission or nutrient surplus depend on the location, even a county resolution might produce misleading results. The aim of this article is to propose a Bayesian approach which combines two sorts of information, with one being treated as defining the prior and the other the data to form a posterior, used to estimate a data set at a municipality resolution. We define the joint prior density function based on (i) remote sensing data, thus accounting for differences in county data and missing data at the municipality level, and (ii) the results of a cluster analysis that was previously applied to the micro-census, whereas the data are defined by official statistics at the county level. This approach results in a fairly accurate data set at the municipality level. The results, using the proposed method, are validated by the national research data centre by comparing the estimates to actual observations. The test statistics presented here demonstrate that the proposed approach adequately estimates the production activities.  相似文献   
72.
The high-growth, resource- and pollution-intensive industrialization model that China has pursued has caused severe environmental pollution and deterioration, particularly in a number of clusters in the coastal regions of East and Southeast China, where the Reform and Opening-up policies first started. The lack of uptake of environmental norms/values, deficit of regulatory enforcement of environmental policies, and insufficient institutional capacity have been compounding factors. As environmental standards were raised by China’s central government, the enforcement of environmental regulation has been compromised more in inland China than in coastal regions, due to China’s “decentralized governance structure” and regional disparity in terms of both economic development and environmental pollution. This paper therefore argues that rising environmental regulations, as well as firm characteristics, regional hub effect and political environment, have all been particularly important in forcing China’s pollution-intensive enterprises to restructure their production, through innovation, upgrading, geographical relocation, outsourcing and plant closure, especially in China’s coastal regions. It contributes to recent studies by developing a heuristic analytical framework that aims to be sensitive to the impacts of environmental regulation, political environment and regional hub effect over firm restructuring, but which does so by stressing these impacts are simultaneously inflected by the nature and attributes of firms. The empirical analysis suggests a roughly inverted “U”-shaped relationship between firm relocation tendency and firm size (or firm capability), resulting from complex interactions between political environment, regional hub effect and environmental regulation.  相似文献   
73.
孙燕铭  周传玉 《地理研究》2022,41(10):2742-2759
在长三角更高质量一体化发展的战略背景下,构建区域间环境协同治理体系,是提升区域大气污染治理成效的可行性选择。本文从环境规制的政策文件、实施过程、治理效果3个维度,构建大气污染规制耦合度评价体系,探究长三角区域41个城市2003—2019年大气污染规制耦合度的时空演化特征。以此为基础,对长三角区域各城市划分区域协同治理小组,并分别测算其大气污染治理协同水平,进而探究长三角区域大气污染协同治理的影响因素。结果显示:① 各城市的大气污染规制耦合度整体上表现为连片集聚发展特征,呈现出上海市最高、浙江省和江苏省次之、安徽省再次之的格局,且区域差异性不断缩小;② 长三角区域整体大气污染治理协同度较低,但在波动中呈缓慢上升趋势,划分区域治理组后各小组大气污染治理协同度保持在较高水平;③ 影响因素分析结果表明,地区间对外开放差异、公共交通差异和绿化建设差异对长三角区域大气污染协同治理有着显著的抑制作用,而经济增长差异和技术创新差异具有显著的积极影响。  相似文献   
74.
刘哲  兰措 《地理科学进展》2022,41(2):304-315
气候变化和下垫面变化是影响河道径流的两大驱动力,研究两者对径流的影响有利于深入理解流域水文过程,为水资源管理提供科学依据。鉴于利用不同方法获得的结果存在一定程度的差异,有必要使用多种方法进行交叉验证。论文基于Budyko水量平衡法和新增水库模块的分布式水文模型(DHSVM)法量化了气候变化和下垫面变化对青海省北川河流域径流变化的贡献。结果表明:① 自1960年以来流域出口流量以每年0.037 m3/s的趋势下降,突变年份发生在1969年。② 2种方法的分析结果均表明,年代际尺度上,气候变化对径流影响的贡献率由高到低依次为:1990—1999年>2000—2009年>1970—1979年>1980—1989年=2010—2019年,且下垫面变化是1970—2019年流域出口径流变化的主导因素,对应的贡献率分别为94.58% (Budyko法)和65.68% (DHSVM法)。③ Budyko方法只能揭示流域整体的变化,而DHSVM方法能够体现水文过程变化的时空差异,模型结果表明上中游、下游地区的年平均径流变化分别受气候变化、下垫面变化主导;流域出口处月径流变化则对下垫面条件中的水库调节更敏感。此外,文中就2种方法量化结果差异的原因也展开了讨论。  相似文献   
75.
探讨网络视频应用于建设工程监管领域的系统建设,介绍了系统框架、数据建设、功能设计和技术路线,以重庆市重点建设工程为例进行项目开发并在建委系统取得了试用,最后指出全过程、多传感、集成的体制性建设工程监管系统是未来趋势。  相似文献   
76.
随着浙江省天然气供应规模的逐步扩大,应用领域的不断拓展,用WebGIS对天然气管线进行管理更显其优势。气象条件的变化与天然气供需有着密切的联系,本文基于WebGIS建立了浙江省天然气调控应急保障气象服务系统。对天然气管网数据进行了整理,并结合气象数据进行了分析和统一存储及管理。系统采用B/S架构,实现了天然气管道沿线实况监测、沿线天气预报、沿线气象历史资料查询、管网负荷预测、地图管理和操作、系统管理和维护等功能。探索了气象条件对燃气负荷的影响规律,能及时查询天然气沿线的天气实况和预报,为天然气调控应急保障提供了直观的气象服务和数据保障。  相似文献   
77.
ANANALYSISOFTHEPOLICY-MAKINGINREGULATINGTHEINDUSTRIALSTRUCTUREANDDISTRIBUTIONINTRADITIONALINDUSTRIALBASEINMIDDLELIAONINGPROVI...  相似文献   
78.
水量统一调度以来黄河宁夏河段引黄耗水量分析   总被引:1,自引:0,他引:1       下载免费PDF全文
金双彦  张萍  张春岚  马志瑾 《水文》2015,35(6):82-86
对1999~2012年黄河水量统一调度期间宁夏河段引水和退水的年内和年际变化、引排比关系进行了分析。采用引退水法和水量平衡法计算了宁夏河段的引黄耗水量。结果表明:引退水法平均耗水量为32.64×10~8m~3,年际变化相对比较平缓;水量平衡法平均耗水量为39.37×10~8m~3,年际变化非常明显。建议进一步加强实际引退水口门的数量核实和引退水的监测分析工作。  相似文献   
79.
The question of whether China is on the verge of a ‘shale gas revolution’ is examined. This has potentially significant consequences for energy policy and climate change mitigation. Contrary to the optimistic reading of some commentators, it argues that various technological, environmental, political, regulatory and institutional factors will constrain the growth of China's shale gas market and that such a revolution might in any event have consequences that are at best mixed, at worst antithetical to climate change mitigation.Policy relevanceChina's reserves of unconventional gas have the potential to transform energy policy, as has occurred in the US, resulting in the substitution of shale gas for coal in the energy mix. Because gas emits only approximately half the GHG per unit as coal, such a move would have important implications for climate policy. However, substantial obstacles stand in the way of the ‘energy revolution’ that some policy analysts see China as embarking upon. The need to acknowledge these obstacles, particularly those relating to regulation and governance (and whether or to what extent they can be overcome), is an issue of profound importance to the future of climate and energy policy.  相似文献   
80.
Which actors in the aviation sector ought to be obliged to participate in emissions trading? The European Commission opted for the aircraft operator in their proposal for a Directive. A major drawback is that non-EU aircraft operators might legally challenge their inclusion in this scheme and, if the challenge was successful, discrimination between EU and non- EU operators would undermine the scheme. An alternative would be to place an obligation on fuel suppliers to prove possession of allowances, thus avoiding discrimination. However, emissions trading can be evaded to some extent by increased refuelling beyond EU boundaries (tankering). Typical city pairs were used to analyse the conditions under which such tankering strategies are economically attractive. The analysis shows that the attractiveness of tankering depends substantially on the relationship between fuel prices and allowance prices. If the price relation as of March 2006 is taken as a basis, tankering would be attractive within a radius of up to 4,000 km especially on southbound and eastward routes. Emissions trading could, under unfavourable conditions, be evaded for up to 20% of the total fuel consumption in aviation with the help of tankering. Although this value is only a theoretical upper limit, more than 10% of fuel consumption could be affected by tankering.  相似文献   
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