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131.
132.
Conventional approaches to evaluation of environmental programs have tended to limit themselves to restricted measures of program effectiveness. This paper shows how a social learning approach can be incorporated into evaluating public environmental programs. A social learning approach is particularly suited to complex environmental challenges which are inherently difficult to understand, predict, and manage, thus complicating the evaluation process. The paper presents an Australian case study of dryland salinity management where there are major knowledge barriers impeding conventional management techniques. The research presented in this paper focused on evaluating a public demonstration program to track its impact through its design, implementation, and monitoring phases. The paper shows that, by incorporating social learning principles and practices, program evaluation can promote collective action, critical reflection, and increased knowledge to underpin improved environmental management.  相似文献   
133.
Logging has been a much maligned feature of frontier development in the Amazon. Most discussions ignore the fact that logging can be part of a renewable, environmentally benign, and broadly equitable economic activity in these remote places. We estimate there to be some 4.5 ± 1.35 billion m3 of commercial timber volume in the Brazilian Amazon today, of which 1.2 billion m3 is currently profitable to harvest, with a total potential stumpage value of $15.4 billion. A successful forest sector in the Brazilian Amazon will integrate timber harvesting on private lands and on unprotected and unsettled government lands with timber concessions on public lands. If a legal, productive, timber industry can be established outside of protected areas, it will deliver environmental benefits in synergy with those provided by the region’s network of protected areas, the latter of which we estimate to have an opportunity cost from lost timber revenues of $2.3 billion over 30 years. Indeed, on all land accessible to harvesting, the timber industry could produce an average of more than 16 million m3 per year over a 30-year harvest cycle—entirely outside of current protected areas—providing $4.8 billion in returns to landowners and generating $1.8 billion in sawnwood sales tax revenue. This level of harvest could be profitably complemented with an additional 10% from logging concessions on National Forests. This advance, however, should be realized only through widespread adoption of reduced impact logging techniques.  相似文献   
134.
Following the intent of the National Environmental Policy Act of 1969, many states have adopted policies and procedures directing state agencies and local government units to evaluate the potential environmental impacts of development projects prior to their undertaking. In contrast to a rich literature on federal requirements, current understanding of state environmental review is narrowly focused and outdated. This paper seeks to provide information on the landscape of state environmental review policy frameworks. The paper identifies 37 states with formal environmental review requirements through a document review of state statutes, administrative rules and agency-prepared materials, and confirms this finding through a survey of state administrators. A two-tier classification is used to distinguish states based on the approach taken to address environmental review needs and the scope and depth of relevant policies and procedures implemented. This paper also provides a discussion of policy and programme attributes that may contribute to effective practice, and of the potential for adopting relevant legislation in states where environmental review is currently lacking.  相似文献   
135.
苏通大桥及沪崇苏通道的建设将引致区域交通格局的演化,从而对相关地区经济社会发展产生深远影响。对于相对落后的南通市而言,快速过江通道建设既是促进发展的良好机遇,同时也将带来新的挑战和威胁:(1)交通可达性改善明显,南向联系趋于便捷,运输成本相应减小,要素集聚呈现加速态势,但优质要素面临流失威胁;(2)产业规模迅速扩张,但以低层次产业为主,进一步加大了产业层次提升的压力,同时建设用地的盲目扩张和散乱布局,使得空间开发无序风险加剧;(3)进入上海都市圈的紧密圈层,有望成为长江三角洲北翼重要的次中心城市,但面临的竞争压力也不断增大。为促进南通市的可持续发展,政府部门应在推进都市区建设、促进要素集聚、空间资源的合理和统筹利用等方面制定科学有效的区域政策。  相似文献   
136.
This paper focuses on comparative review and analysis of the systems of environmental protection, national environmental strategies and fundamentals of environmental legislation in Australia and the Russian Federation. These countries have many socioeconomic similarities, such as low population densities and richness in natural resources which are largely exported. The main disparity between Australia and Russia is in the types of economy. This paper ‘continues’ the sequence of recent scholarly publications on comparison of various features of environmental policies in the countries from all over the world. Comparative analysis in this research has been based on examination of scholarly publications, legislation, government documents, mass media sources and NGO responses. The analysis has revealed a number of differences including top-down implementation of policies in Russia whereas in Australia, each State (Territory) implements policies with significant independence from the Commonwealth Government. At the same time, similarities between the countries have been identified: for example, in deficits in the budget of local environmental authorities and in the presence of contradictions in legislation at national and regional levels of government. Suggestions resulting from this analysis include further integration of sustainable development strategies at all levels of Australian government to encourage further protection of the environment and, for Russia, creating a separate Ministry of Environmental Protection. These approaches should assist facilitation of sustainable development for both nations. Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue.  相似文献   
137.
厌氧发酵沼气工程的工艺及存在的问题   总被引:2,自引:0,他引:2  
利用厌氧消化技术处理畜禽养殖废水,制取清洁能源——沼气,在治理污染的同时变废为宝,减少温室气体的排放,从而实现国民经济的可持续性发展。本文概述了集约化畜禽养殖场废污水处理中采用的厌氧发酵工艺,以及厌氧发酵沼气工程中存在的问题。  相似文献   
138.
基于协整和因果分析的我国安全生产宏观政策干预研究   总被引:1,自引:1,他引:0  
为进一步分析我国安全生产政策的实施效果及存在问题,根据政策时效干预度量化模型,采用协检验、格兰杰因果检验和脉冲响应分析等计量方法对1978-2006年我国特别重大事故发生趋势与政策时效干预力度关系进行量化分析,得出特别重人事故的发生与政策时效干预力度问存在长期均衡关系,且在10%的显著水平下,特别重大事故的发生是政策时效干预力度加强的格兰杰原因.同时分析表明,目前我国安全生产政策干预表现出两大缺点:被动性和滞后性.因此,应逐步开展生产安全事故宏观预警与政策模拟等研究,为提高安全生产宏观政策干预的主动性和前瞻性提供技术支持.  相似文献   
139.
2016年《巴黎协定》的正式生效是全球环境治理的重要里程碑,是国际社会在应对气候变化的艰难进程中迈出的重要一步,标志着全球环境治理从此进入履约阶段。本文基于宾夕法尼亚大学智库与公民社会项目(TTCSP)公布的《2015年全球智库指数报告》,选取其中排名前十位的国际环境智库的研究报告和环境领域中代表性学者的相关论文,对国外学术界有关《巴黎协定》履约前景的分析进行了系统梳理,并对此做出简要评述。文章在肯定《巴黎协定》有力推进国际气候治理进程的同时,也指出在新的国际形势之下,尤其是在英国正式启动脱欧进程和特朗普新任美国总统后,其履约过程中更是存在着协定之内和协定之外的众多挑战和不确定性,本文的基本结论如下:首先,协定之内面临着协定缔约方国内批准程序上的挑战;国家自主贡献的实现与发展中国家能力建设;2℃温升目标的实现前景;审评和盘点的效力评估;碳市场机制能否有效运行。其次,协定之外面临着英国脱欧的潜在气候政策变化及影响;美国气候政策的可能变化及其影响。基于对以上智库报告和相关研究论文的分析,笔者对《巴黎协定》的履约前景得出几点看法:(1)正视国际气候合作的机遇与挑战;(2)对具体议题的落实需充满信心;(3)理性冷静看待英美气候政策的可能变化;(4)鼓励环境类国际组织之外的非国家行为体展开通力合作。对此,我们应正视履约中的挑战与不确定性,做好充分的应对之策,确保履约进程的顺利完成。总之,《巴黎协定》的履约前景不容乐观,国际社会任重道远。  相似文献   
140.
发展生态循环农业是我国新时期转变农业发展方式的战略选择,农户是生态循环农业的经营主体和利益相关者,厘清农户参与生态循环农业的根本动机,对于制定有效的生态循环农业推广措施具有重要意义。文章基于湖北省391份农户调查数据,首先,在文献回顾的基础上提出市场收益、政策激励对农户生态循环农业从事意愿与行为影响路径的基本假设,并利用OLS方法分析市场收益和政策激励对农户从事生态循环农业意愿与行为的影响;其次,运用优势分析法评估市场收益类变量和政策激励类变量影响农户意愿与行为过程中的相对重要性;最后,通过交互效应检验市场收益类变量和政策激励类变量间的交互作用。结果表明:收入预期对农户从事生态循环农业的意愿与行为均有直接的积极影响,是促进农户从事生态循环农业的最重要的因素;焚烧秸秆惩罚政策和废弃物资源化补贴政策对农户从事生态循环农业的意愿有积极影响,沼气池建设补贴政策和废弃物资源化补贴政策对农户生态循环农业行为有促进作用;收入预期与废弃物资源化补贴政策在影响农户生态循环农业行为的过程中存在互补效应。本研究认为,市场收益是刺激农户采纳生态循环农业生产模式的首要因素,因此,要着力完善生态农业市场体系,增强生态农产品的市场竞争力,提升农户对生态循环农业的盈利信心;另外,政策激励对于农户采纳生态循环农业具有促进作用,应该做到约束与激励并行,同时注意加强农业政策的科学设计与落实执行。  相似文献   
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