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941.
以四川藏区矿产资源的开发利用为研究对象,一方面,从环境公害本土化的视角解读四川藏区的资源开发公害问题;另一方面,从法律的价值和应对的视角对资源开发公害问题进行法律规制,以期对四川藏区生态环境的保护有所裨益。  相似文献   
942.
从行为参与、管理参与和环境意识三个方面阐述了当前环保事务参与中存在的性别差异问题;从社会结构的视角分析了性别化对环保参与现状的影响。针对存在的问题和制约因素,从社会系统、社会资源和环境意识三个方面提出发展建议。  相似文献   
943.
对杭州市环保系统的人才总量、学历结构、专业结构、职称结构和年龄结构等方面作了较详细的分析;针对杭州市环保系统存在的人才总量不足、结构分布不合理和高层次人才匮乏等问题,提出了引进高层次人才、加强教育培训、壮大基层队伍等对策。  相似文献   
944.
引入投影降维的思想,将遗传投影寻踪与回归分析技术运用到城市环境质量评价中。将此技术与神经网络方法进行实例比较,投影寻踪回归方法不但可以合理地作出环境质量的综合评价,而且消除了神经网络方法中类别判断不够精确的影响。  相似文献   
945.
Patterson, Lauren A., Jeffrey Hughes, Glenn Barnes, and Stacey I. Berahzer, 2012. A Question of Boundaries: The Importance of “Revenuesheds” for Watershed Protection. Journal of the American Water Resources Association (JAWRA) 48(4): 838‐848. DOI: 10.1111/j.1752‐1688.2012.00655.x Abstract: Watersheds transcend jurisdictional boundaries; raising important questions of who should pay for watershed protection, and how can watershed governance be funded? The responsibility and cost for watershed protection has progressively devolved to local governments, resulting in additional negative externalities and financing challenges. Watershed governance structures have formed at the scale of the watershed, but they often lack the financing mechanisms needed to achieve policy goals. Financing mechanisms via local governments provide a reliable source of revenue and the flexibility to address watershed specific issues. We develop a “revenueshed” approach to access the initial challenges local governments face when seeking to finance trans‐jurisdictional watershed governance. The revenueshed approach engages local governments into discussion and implementation of financial strategies for collaborative watershed governance. Legislation places water quality regulations primarily on local governments inside the watershed. The revenueshed approach extends the financial and stewardship discussion to include local governments outside the watershed that benefit from the watershed. We applied the revenueshed approach to the Mills River and Upper Neuse watersheds in North Carolina. Mills River had a partnership governance seeking revenue for specific projects, whereas the Upper Neuse sought long‐term financial stability to meet new water quality legislation.  相似文献   
946.
Newburn, David A. and Richard T. Woodward, 2011. An Ex Post Evaluation of Ohio’s Great Miami Water Quality Trading Program. Journal of the American Water Resources Association (JAWRA) 48(1): 156‐169. DOI: 10.1111/j.1752‐1688.2011.00601.x Abstract: Market‐based approaches to address water quality problems have resulted in only limited success, especially in trading programs involving both point and nonpoint sources. We analyze one of the largest point‐nonpoint trading programs – the Great Miami Trading Program in Ohio, administered by the Miami Conservancy District (MCD). Our evaluation focuses on the economic and institutional aspects of the program, including cost effectiveness, efficiency of bidding, transaction costs, trading ratios, and innovation. We use a unique dataset consisting of all bids from agricultural nonpoint sources and interviews of soil and water conservation district (SWCD) agents in the watershed. We find that the MCD’s reliance on county‐level SWCD offices to recruit and advise farmers has been essential to achieve relatively high rates of farmer participation. Additionally, the MCD is able to partly free ride on the administrative costs that SWCD offices receive to assist federal conservation programs, which is helpful to lower costs for a fledgling trading program. However, the involvement of SWCD offices reduced the potential cost savings from the reverse auction structure because some agents were able to learn about the threshold price over the six rounds of bidding and help farmers bid strategically. Overall, the program structure serves as an effective model for future trading programs in other regions that seek to involve agricultural nonpoint sources.  相似文献   
947.
An important implication of agricultural modernization has been the break-down of interlinkages between farming, ecology and society. Historically, farming systems evolved from the specific responses of farming communities to local ecological conditions. The totality of regionalized farming systems arising out of this co-production moulded the countryside into an ‘archipelago’ of differentiated ruralities. During the period of agricultural modernization, the nature of co-production changed thoroughly. The natural elements in co-production were increasingly artificialized or replaced by industrial artefacts. This paper analyses the emergence of environmental cooperatives in the Netherlands as a movement towards a renewed embedding of farming in its local environment. Environmental cooperatives are local farmers associations that promote activities related to sustainable agriculture and rural development and claim to be actively involved in effectuating rural policies in their locale. Since the foundation of the first cooperative in 1992, numbers have rapidly grown to over 100. This paper examines the genesis and practices of environmental cooperatives and assesses their socio-economic and ecological impact. The importance lies most of all, so the authors contend, in that they represent valuable ‘field laboratories’ for building stimulating and supportive institutional contexts for remodelling Dutch farming along the lines of environmental and economic sustainability. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   
948.
在北京地区某加油站开展的前期石油类污染物自然衰减现场试验的基础上,进一步开展了验证试验,结果表明本次试验得到的挥发性有机物(VOCs)变化趋势及O2、CO2含量沿土壤深度分布和前期试验结果呈现相同的规律,说明基于自然衰减法设计实施的加油站现场试验检测分析结果可靠,试验方法具有合理性、可操作性及可重复性.进一步的理论分析对前期试验结果进行了验证,得出以下结论:(1)通过氧平衡和碳平衡计算对加油站土壤内的自然衰减方式进行评价,验证了该加油站地下土壤中实际发生的微生物降解既有需氧降解也有厌氧降解;(2)利用有机物的一级衰减模型对该污染现场土壤中石油类污染物的降解速率和半衰期进行计算表明,2次试验计算得到的石油类污染物的半衰期基本一致,该污染现场石油类污染物的半衰期为50 d左右;(3)在此基础上,对该加油站包气带土壤的自然衰减能力和环境质量进行评价,2次试验结果均表明该污染现场在自然衰减的作用下已经不存在环境风险.  相似文献   
949.
通过单因子实验考察了无硫膨胀石墨制备过程中氧化剂及插层剂用量、氧化反应及插层反应时间、氧化反应及插层反应温度对无硫膨胀石墨膨胀体积的影响。通过正交实验确定了制备无硫膨胀石墨的最优条件是:石墨(g)∶浓硝酸(mL)∶30%H2O2(mL)∶乙酸酐(mL)=1∶2.25∶0.25∶0.6,在30℃条件下氧化反应60 min,加入插层剂后在60℃条件下插层反应90 min,此条件无硫膨胀石墨的膨胀体积达317 mL/g使用XPS、FT-IR、XRD和SEM对无硫膨胀石墨进行了表征并对其吸油性能和再生性能进行了研究。结果表明,所制备无硫膨胀石墨对原油和柴油的最大吸附量分别为66.3 g/g和62.7 g/g。吸附原油后的无硫膨胀石墨抽滤再生后首次再生率为49.1%,原油的回收率为64.5%。  相似文献   
950.
垃圾焚烧过程的不稳定会导致大量有害物质的生成,为确保垃圾的清洁燃烧需要将炉膛温度控制在850℃以上,为此测试了焚烧炉运行的主要可控参数对炉膛温度的影响。结果表明,垃圾堆放位置在垃圾池深3~8 m处,并经过6 d以上发酵脱水后适合焚烧;炉膛温度随给料量、一次风率和一次风温增加而增大,随过量空气系数增加而降低,其中给料量宜控制在95%~110%之间;当过量空气系数为1.6、一次风率为90%、一次风温为260℃、给料量为100%时炉膛温度达901℃。  相似文献   
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