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81.
客观评价大都市郊野乡村多功能及空间布局特征,是分类制订精细化乡村振兴策略的关键之一。通过构建大都市郊野乡村“生态环境—休闲文化—农业生产—经济发展—生活保障”多功能评价方法,使用多源空间数据、统计数据及调查数据,评价上海郊野89个镇的多功能值,提出镇域多功能发展类型及空间布局特征。结果表明:(1)上海市89个镇多功能发展存在显著差异。各项功能按照均值排序为生态环境(0.7674)>经济发展(0.6054)>农业生产(0.5882)>生活保障(0.5238)>休闲文化(0.2525);(2)生态环境高值区域主要分布在崇明岛、青浦西部和奉贤南部,农业生产高值区主要位于浦东南部、奉贤及金山、崇明南部和青浦,经济发展高值区主要位于中心城周边和新城周边区域的28个镇,生活保障低值区主要位于紧邻中心城与最偏远区域两类共29个镇,休闲文化高值区主要位于与中心城距离最偏远的松江、青浦、金山;(3)郊野镇多功能发展可划分为高均衡型、低均衡型和非均衡—混合发展型、非均衡—传统维持型和非均衡—城市化型共五种模式,仅浦江镇等10个镇为多功能高均衡发展模式,占11.24%。论文建立的评价方法及研究结论可为探索精细化都市郊野乡村振兴政策提供理论依据。  相似文献   
82.
ABSTRACT The term “institution” and several variants are used frequently in the literature on metropolitan water management. The state-of-the art investigation on which this paper is based revealed that 1) many uses of the term do not include careful definitions; 2) many users of the term seemed unaware of the general, theoretical literature on the subject of institutions; 3) there was little consistency among uses, either in the practical literature dealing with water or in the conceptual literature dealing with theories of institutions or institutionalization; 4) some usages were without significant meaning; 5) in many cases the term was used as a kind of “black box” to account for behavioral, societal, or managerial factors; 6) the term was often used as a synonym for “organization”. This latter use is frequently found in federal reports, including National Water Commission studies, and is most unfortunate because it tends to slight significant social-psychological factors. A suggested definition is: “An institution is the structured result or outcome of a process by which values are articulated, arranged, and communicated, having continuity over time, and influencing behavior of persons who did not necessarily participate in formulating those values (norms).”  相似文献   
83.
Substantial equivalence (SE) has beenintroduced to assess novel foods, includinggenetically modified (GM) food, by means ofcomparison with traditional food. Besides anumber of objections concerning its scientificvalidity for risk assessment, the maindifficulty with SE is that it implies that foodcan be qualified on a purely substantial basis.SE embodies the assumption that only reductivescientific arguments are legitimate fordecision-making in public policy due to theemphasis on legal issues. However, the surge ofthe food debate clearly shows that thistechnocratic model is not accepted anymore.Food is more than physico-chemical substanceand encompasses values such as quality andethics. These values are legitimate in theirown right and require that new democraticprocesses are set up for transverse,transdisciplinary assessment in partnershipwith society. The notion of equivalence canprovide a reference scale in which to examinethe various legitimate factors involved:substance (SE), quality (QualitativeEquivalence: QE), and ethics (EthicalEquivalence: EE). QE requires that newqualitative methods of evaluation that are notbased on reductive principles are developed. EEcan provide a basis for the development of anEthical Assurance as a counterpart of QualityAssurance in the food sector. In France, asecond circle of expertise is being set up toaddress the social issues in food public policybeside classical risk assessment by the firstcircle of expertise. Since ethics is likely tobecome an organizing principle of the secondcircle, the equivalence ethical framework canprove instrumental in this context.  相似文献   
84.
燃气-蒸汽联合发电是利用原油、重油、渣油和天然气作燃料,综合效率高于常见的火,供电效率明显领先于其它形式的发电设备,具有广泛使用的潜力.通过对其环境空气污染物排放量计算方法的初步研究,论述了燃气-蒸汽联合循环燃油机组工程环保设计中应注意的一些问题.  相似文献   
85.
依据赣江流域的系统特征,选择工业开发模式,是地域经济发展的战略核心问题。推进资源有效利用与高度利用,优势产品开发与替代产品开发,实现经济发展趋于由下游而上游的资源型—加工型—技术型产业结构指向的有序转化,资源开发与国土冶理趋于由上游而下游的生态经济良性循环,为赣江流域工业开发模式的基本要点。  相似文献   
86.
土地利用/覆被变化(LUCC)环境效应研究综述   总被引:9,自引:0,他引:9  
土地利用/覆被变化能直接反映当今全球环境变化的主导因子--人类活动,为此土地利用/覆被变化产生的环境问题已引起人类社会的广泛关注,深入研究这些问题具有重要的理论意义和实践价值.针对土地利用/覆被变化引起的环境效应的复杂性、累积性,本文在总结国内外LUCC环境效应的研究成果的同时,把LUCC环境效应分为:土壤环境效应、大气环境效应、水环境效应以及生态效应四类进行阐述,并结合目前研究在内容和方法方面存在缺乏统一的指标体系、研究区域时空尺度单一、以单要素静态研究为主、实验研究相对薄弱以及动态模拟不够等问题对其发展趋势进行了探讨.  相似文献   
87.
ABSTRACT Methods of institutional coordination derived from the applied behavioral sciences have been useful in determining the policy planning, and implementation responsibilities that must be shared between local governments, watershed districts, and a regional planning body in the Minneapolis-St. Paul Metropolitan Area. The confines of the traditional behavioral science models of organizations and institutional change processes, and the realities of administrative systems imbedded in political processes at both the local and state levels, have created conflicts between regional planners, watershed district staff and consultants, and municipal administrators. A conceptual framework based on work by Selznick on institutions was applied to two watershed districts, and the results evaluated for other research purposes as well as policy development for the 1973 Minnesota legislative session.  相似文献   
88.
环境保护是武汉城市圈建设资源节约型环境友好型社会的重中之重,当前武汉城市圈环境污染问题突出,严重制约了两型社会的建设。文章分析了目前武汉城市圈环境保护工作中存在的问题,包括环境管理机制不顺畅、环境执法中市场作用发挥不足、循环经济相关法律法规滞后、“重污染防治、轻生态保护”的观念盛行等,最后,本文从法治的角度提出了解决目前环境问题的合理化对策。  相似文献   
89.
Political inaction at the federal level in the United States has driven increased attention to the importance of planning for climate change at the metropolitan level. This study reports on a survey of 25 regional councils in the United States that measures the extent to which they have adopted climate change plans and to identify the factors that influence their ability to implement climate change initiatives. The findings revealed that a majority of regional councils are involved in planning for and seeking to reduce climate change, and that existing efforts in complementary policy domains make this involvement possible. The findings support a multi-level framework to assess the institutional capacity of regional councils to implement climate change policy and planning in a metropolitan area.  相似文献   
90.
环鄱阳湖旅游圈旅游经济联系与区域发展策略   总被引:1,自引:0,他引:1  
旅游圈是推进区域旅游发展的有效载体,对区域内各地区间旅游经济关系产生重要影响。以资源主导型的环鄱阳湖区域为例,根据该区域旅游经济现状,以该研究区5个地级市所属的国家3A级及以上67个旅游景区为研究对象,从景区景观质量引力指数、旅游规模和交通可达性对传统引力模型进行修正,测度2003~2015年各地区间旅游经济联系强度及其演变情况,揭示环鄱阳湖区域旅游经济联系总量呈现出快速增长且联系紧密、区域差异较明显、交通作用逐渐增强等特征。在此基础上,提出构建环鄱阳湖旅游圈区域旅游发展的基本模式,以及圈内各地旅游经济联系的思路,形成多极核的网络化结构旅游圈层格局,并演进为区域旅游圈的一般结构模式,为推进区域旅游可持续发展提供借鉴。  相似文献   
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