共查询到20条相似文献,搜索用时 406 毫秒
1.
2.
工业化进程的加快使得工业水资源需求不断增加,工业废水排放量也越来越大,如何提高工业用水效率从而缓解水资源压力成为日益严峻的问题。本文选取工业用水量、工业就业人数、工业固定资本和工业废水治理费用作为投入指标,以工业增加值与工业废水排放量作为期望与非期望产出指标。首先利用EBM模型计算长江经济带2008—2017年工业用水效率,其次利用泰尔指数来分析工业用水效率的区域差距,最后利用面板Tobit模型来分析影响不同地区工业用水效率的驱动因素。结果显示,近年来长江经济带的工业用水效率呈波动下降趋势,不同地区效率差异明显;经济发展水平、工业化程度、技术水平、水资源禀赋和政府环境管制力度对长江经济带的工业用水效率都有一定影响,但存在地区差异。 相似文献
3.
基于要素资源配置效应、技术创新效应和竞争效应,本文梳理了市场分割对长江经济带能源环境效率的影响机制,基于省际面板数据实证检验,发现:长江经济带能源环境效率随着市场分割程度存在显著倒"U"形关系;在规模报酬递减作用下,市场分割对长江经济带能源环境效率的影响从提升转变为抑制。未来破除长江经济带能源环境效率提升瓶颈的关键在于研发投入、对外开放水平以及市场融合。另外,分样本回归表明市场分割导致长江经济带中游地区能源环境效率存在"中部塌陷"的风险。由此,加强研发资金的精准投入、提升对外开放度和中游地区支撑力,以及增强长江经济带生态协同是长江经济带提升能源环境效率的重要突破口。 相似文献
4.
为实现碳达峰与碳中和的目标,亟需对生态环境进行治理和保护,测度以往政策工具对环境治理的效果有利于及时调整治理措施。本文利用2004—2015年中国30个省份的数据,采用非期望产出SBM模型分析各省环境治理效率存在显著差异,并通过空间杜宾模型研究异质性环境规制及产业发展对环境治理效率的影响。结果表明:(1)各省环境治理效率存在显著差异,环境治理效率呈现波动。(2)异质性环境规制呈现不同的治理效率。命令型环境规制与环境治理效率正相关,推行环保法规有利于环境污染治理;市场型环境规制与环境治理效率负相关但不显著;自主型环境规制与环境治理效率正相关,公众积极参与有利于环境污染治理。(3)环境规制模式通过政府能力影响环境治理效率。通过中介效应,政府环保投入能力起到了部分中介效应作用,命令型环境规制和自主型环境规制通过政府环保投入能力提高了环境治理效率。 相似文献
5.
6.
7.
8.
9.
姜玮许新宇姜圣华宋勇祥 《资源开发与市场》2015,(4):423-426
在传统DEA的基础上引入交叉评价机制和虚拟决策单元,对2009—2012年河西20个县域的农业经济效率进行了研究,以克服传统DEA无法区分有效单元之间的优劣和明确各决策单元的提升潜力,并对河西地区农业经济效率变化趋势进行收敛性检验。研究发现,2009—2012年河西地区农业经济效率普遍很低,县域间差异较为显著,且呈扩大趋势;河西地区目前主要介于低投入低产出和高投入高产出阶段,农业经济效率具有很大提升空间。 相似文献
10.
11.
Greater emphasis is being placed on indicators of agri-environmental efficiency of organic production systems. Linking environmental measures with profitability measures based on net income is the only way to develop such indicators. A stochastic production frontier model that explicitly incorporates farm decisions about acquiring and managing organic soil-improving inputs is used to measure efficiency. The results confirm that on-farm self-sufficiency in soil-improving inputs is positively related to farm-level efficiency. 相似文献
12.
Planning for change and sustainability in water development in Lao PDR and the Mekong River basin 总被引:1,自引:0,他引:1
Jeffrey W Jacobs 《Natural resources forum》1996,20(3):175-187
With its recent opening to the global market economy, the natural resources of the Lao People's Democratic Republic (Lao PDR, referred to in this paper as Laos) – especially its water resources–have attracted external interest and investment. The overall level of water development is low. While even modest development would help Laos meet some of its urgent needs, past experience in Southeast Asia and other tropical regions suggests that fast-paced water development may damage the natural resource base. This article examines some efforts in water development from Southeast Asia and other regions and their relevance to water policy formulation in Laos. Future social and environmental changes in Laos are inevitable, but the nature and direction of these changes are uncertain. It thus makes sense to design policies that are flexible and can be adjusted to, and even take advantage of, a changing social and environmental context. Smaller-scale, deliberately-paced projects which merge local knowledge and external expertise fulfil the requirements of flexibility and adjustability, and are also appropriate for other important reasons: they do not require massive inputs of funding, and they do not initiate large-scale environmental and socio-economic changes. Current knowledge of the complex ecological and social systems in Laos is only sketchy. A slower-paced development will allow developers the necessary time to learn more about these important aspects. 相似文献
13.
A method is presented which combines environmental indices and estimates of inputs from various land uses to aid in environmental impact assessments. Unweighted pair/group cluster analyses are used to obtain relationships between easily observable environmental indices, such as vegetation types, soils, and geology, based on their mutual recurrence. These relationships are shown by using an ordination technique which shows the nature of complex impacts on a natural system. Results are used to develop anenvironmental effects sequence diagram based on known scientific and engineering principles and observed natural relationships. The diagram may be used in conjunction with land use data to estimate the possible magnitude of impacts on the pre-existing system which may result from such land use. Several examples are developed which quantify inputs from various land uses and which compare them with environmental inputs including point source and non-point source liquid and atmospheric emmissions, land modifications, and resource consumption. Known average values are used and a separate comparison is made in describing the vast differences between the project phases of construction versus longterm operation. A hypothetical environmental impact assessment is given for a small residential development in Chambers County, Texas, U.S. of A. 相似文献
14.
Technical- and Environmental-Efficiency Analysis of Irrigated Cotton-Cropping Systems in Punjab,Pakistan Using Data Envelopment Analysis 总被引:1,自引:0,他引:1
Cotton cropping in Pakistan uses substantial quantities of resources and adversely affects the environment with pollutants from the inputs, particularly pesticides. A question remains regarding to what extent the reduction of such environmental impact is possible without compromising the farmers’ income. This paper investigates the environmental, technical, and economic performances of selected irrigated cotton-cropping systems in Punjab to quantify the sustainability of cotton farming and reveal options for improvement. Using mostly primary data, our study quantifies the technical, cost, and environmental efficiencies of different farm sizes. A set of indicators has been computed to reflect these three domains of efficiency using the data envelopment analysis technique. The results indicate that farmers are broadly environmentally inefficient; which primarily results from poor technical inefficiency. Based on an improved input mix, the average potential environmental impact reduction for small, medium, and large farms is 9, 13, and 11 %, respectively, without compromising the economic return. Moreover, the differences in technical, cost, and environmental efficiencies between small and medium and small and large farm sizes were statistically significant. The second-stage regression analysis identifies that the entire farm size significantly affects the efficiencies, whereas exposure to extension and training has positive effects, and the sowing methods significantly affect the technical and environmental efficiencies. Paradoxically, the formal education level is determined to affect the efficiencies negatively. This paper discusses policy interventions that can improve the technical efficiency to ultimately increase the environmental efficiency and reduce the farmers’ operating costs. 相似文献
15.
Spatial and temporal drivers of zoonotic pathogen contamination of an agricultural watershed 总被引:1,自引:0,他引:1
Jokinen CC Edge TA Koning W Laing CR Lapen DR Miller J Mutschall S Scott A Taboada EN Thomas JE Topp E Wilkes G Gannon VP 《Journal of environmental quality》2012,41(1):242-252
In regions where animal agriculture is prominent, such as southern Alberta, higher rates of gastrointestinal illness have been reported when compared with nonagricultural regions. This difference in the rate of illness is thought to be a result of increased zoonotic pathogen exposure through environmental sources such as water. In this study, temporal and spatial factors associated with bacterial pathogen contamination of the Oldman River, which transverses this region, were analyzed using classification and regression tree analysis. Significantly higher levels of fecal indicators; more frequent isolations of Campylobacter spp., Escherichia coli O157:H7, and Salmonella enterica spp.; and higher rates of detection of pig-specific Bacteroides markers occurred at downstream sites than at upstream sites, suggesting additive stream inputs. Fecal indicator densities were also significantly higher when any one of these three bacterial pathogens was present and where there were higher total animal manure units; however, occasionally pathogens were present when fecal indicator levels were low or undetectable. Overall, Salmonella spp., Campylobacter spp., and E. coli O157:H7 presence was associated with season, animal manure units, and total rainfall on the day of sampling and 3 d in advance of sampling. Several of the environmental variables analyzed in this study appear to influence pathogen prevalence and therefore may be useful in predicting water quality and safety and in the improvement of watershed management practices in this and other agricultural regions. 相似文献
16.
中国煤电行业的发展伴随着各种环境风险,本文以典型煤电企业为例,在产能过剩、能效标准提高、环境保护税、全国碳市场、水资源税和非水可再生能源规划目标的风险约束下,建立环境成本内部化和环境风险分析工具,考虑不同压力情境下对煤电企业价值的影响,构建环境风险影响财务成本的压力测试框架。结果表明,对单个风险而言,产能过剩和碳市场风险对企业价值的影响是大多数地区在不同情景中面临的主要风险驱动因素。对于综合风险压力测试而言,各地区1 000MW超超临界机组乐观情景及悲观情景的企业价值距合理回报预期企业价值相差小,而300MW和600MW亚临界机组因能效水平低、经营成本高等原因在环境风险压力下企业价值偏离合理回报较多。随着环境风险严重程度的不断增加,环境压力测试有助于煤电企业和金融机构了解环境风险对企业财务状况的影响,从而对投资决策产生影响。 相似文献
17.
孙凯 《中国环境管理干部学院学报》2008,18(1):49-52,100
本文从议程设定、议题综合度、参与度及机构设置等方面对三次联合国全球环境大会的绩效进行考察,认为1992年环境与发展大会绩效最高,1972年人类环境会议次之,2002年世界可持续发展峰会最低.这也折射出"后约翰内斯堡时代"环境治理的艰巨性,主要表现在国际条约执行难、某些国家政治意愿的缺失及国际社会的"绿色疲惫"等方面. 相似文献
18.
“放管服”背景下以环评为核心的环境准入体系面临工作周期长、制度效率低、结论可验证性差、社会认可度不高等诸多挑战。本文针对“三线一单”具有的早期介入和共享区域基础信息的工作特征,认为将“三线一单”纳入环境准入体系后可以更好地发挥系统性预防作用,提升政府的决策能力和环评工作效率,实现环境准入体系的高质量和高效率。在重构环境准入体系方面,提出了“三线一单”与规划环评和项目环评制度衔接的关键环节:明确三项制度不同的职责定位和责任主体、厘清三项制度的衔接环节,以及完善三项制度间的信息交互。 相似文献
19.
As a policy instrument for sustainable development, nationwide circular economy (CE) mode has been implemented for 7 years by the Chinese government, to overcome the dilemma among economic depression, energy shortage and environmental pollution. Unfortunately, few literatures contribute to checking the efficiency of regional CE and exploring the potential reasons in China, which will be practically helpful in guiding China's future development and providing reference for other developing countries that will adopt CE mode. Therefore, this paper puts forward the method of super-efficiency DEA window analysis to dynamically evaluate CE efficiency of 30 regions in China covering the period of 2005–2010. In line with the features of CE, the specific efficiency of three sub-systems, namely resource saving and pollutant reducing (RSPR) sub-system, waste reusing and resource recycling (WRRR) sub-system and pollution controlling and waste disposing (PCWD) sub-system, was assessed and compared regarding time series trend and spatial distribution, based on which, the comprehensive CE efficiency was totally ranked. The results show that, on the one hand, during the period of 2005–2010, Chinese CE efficiency slightly increased, implying a significant policy effect of CE; on the other hand, the efficiency of different sub-systems varies, with RSPR sub-system the lowest, and WRRR and PCWD sub-systems relatively higher. In terms of regional distribution, the efficiency of RSPR sub-system in the east area dominates during the whole period. However, for the other two sub-systems, from 2005 to 2007, the efficiency scores of the east fluctuate, then after 2007, the east area became more efficient than the central and the west areas. Throughout the study period, the RSPR sub-system in the central area stably maintains low efficiency, and so does the WRRR sub-system in the west area. The difference in regional efficiency of three sub-systems reflects the difficulty of carrying out CE policy in China comprehensively, which means that, promoting the adaptability of regional policy for local government and enhancing the coordination among various policies for China's central government are the key concerns for realizing sustainable development. 相似文献
20.
突发性环境事件时间序列特征可表征环境风险管理成效及存在问题。研究表明2000年以来中国突发环境事件预防、控制与管理取得了显著成效,其中,突发性水污染事件、大气污染事件以及噪声振动危害年发生频次呈大幅度降低趋势,但固废污染事件自2003年以来的年发生频次变化不大,而其它突发性环境事件自2002年以来的年发生频次则呈快速增长态势,说明中国在强调突发性水环境和大气环境事件监管的同时,还需加强固废污染事件及其它类型突发环境事件的监控与管理。 相似文献