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391.
长江三角洲都市连绵区可持续发展战略研究   总被引:2,自引:0,他引:2  
长江三角洲都市连绵区已成为我国经济最发达的地区之一 ,但与国外发达国家都市连绵区相比面临着一系列资源、环境、产业结构与行政管理等方面的问题。港澳回归并和珠江三角洲结合以及多条新的南北通道出现将使长江三角洲地区在全国的地位遭到进一步的挑战。有鉴于此 ,本文提出一系列实施长江三角洲都市连绵区可持续发展的战略 :(1)建设上海国际经济中心城市 ;(2 )加速城市化进程 ,促进都市连绵区最终形成 ;(3)加大支柱产业、跨国公司、高新技术产业与园区和基础设施投入 ;(4 )加强长江三角洲都市连绵区内部的分工与协作 ;(5)加强政府对区域发展的调控能力 ;(6)开展跨行政区规划 ,促进长江三角洲的持续发展  相似文献   
392.
The systems of Ramenskii's cenobiotic types and Grime's life strategies applied to meadow grasses are compared, and differences between these systems are demonstrated. The parameters of violence of meadow grasses in the aboveground and underground spheres are discussed. The methods for evaluating the degrees of shade tolerance in grasses and their tolerance to sodding are proposed. Two types of explerence are distinguished in meadow grasses (cenophobic and cenofluctuation explerence).  相似文献   
393.
苏州河非点源污染分析及调控对策   总被引:3,自引:0,他引:3  
苏州河一期污水截流工程完成并运行以后,非点源污染对苏州河的污染贡献日益增大,研究苏州河非点源污染的类型,特点,过程并制定相应的治理措施已逐渐成为解决苏州河污染问题的一个主要方面,苏州河非点源污染类型主要包括农业非点源污染,畜禽粪尿污染,城镇及乡村地表径流,底泥二次污染,船舶航运污染以及沿岸码头作业等,在此基础上,指出苏州河市郊段非点源污染严重,支流非点源污染负荷大是目前苏州河非点源污染的两个主要特征,并针对以上问题提出了相应的调控对策。  相似文献   
394.
Fish of a polymorphic and evolutionarily young species Coregonus lavaretusfrom a subarctic lake that has been polluted for more than 60 years are used as an example for analyzing principal trends in the dynamics of structural and functional organization of fish populations. It is shown that fish exposed to sublethal doses of toxic substances for a long time have a smaller body size, the period of their sexual maturation becomes more variable, and the frequency of spawning and life span decrease. The biochemical and bioenergetic mechanisms of variation in populations are analyzed. The ecological expediency of change in the life cycle strategy corresponding to r-selection (conversion to a short reproductive cycle) is substantiated.  相似文献   
395.
Until recently, relatively little attention has been paid to the problem of enforcing mitigation measures identified in environmental impact assessment. Present or proposed enforcement systems in the USA, New South Wales, South Australia, and Western Australia are described and discussed. Although the best enforcement system would depend on the local social, political, and legal systems, five universally desirable features are identified. First, a comprehensive coordinated monitoring and reassessment system is needed. Second, the agencies concerned must have adequate resources to do the work and incentives to carry it out well. Third, there must be the necessary legal powers. Fourth, provision must be made for changing the conditions based on experience. And fifth, the system should be equally effective against private companies and public authorities.  相似文献   
396.
本文在提出人类改造自然过程中所遇到的主要主要矛盾的基础上,运用经济学原理讨论了可持续发展的环境价值观念和生产力优先发展理念对经济发展战略选择的影响,并用动态规划模型予以描述,提出了适宜的经济发展战略的政策建议。  相似文献   
397.
Increased nutrient loading of a body of water leads to an increase in macroalgal growth. It is generally observed, however, that certain species thrive more than others, capitalising on the increased nutrient availability. These are usually small, fast-growing, ephemeral algae that often appear as nuisance blooms. This article discusses the correlation between nutrient increase and macroalgal bloom formation. From a historical perspective, the evolutionary history of nuisance macroalgae, and the habits available to them prior to anthropogenic influences on estuarine geochemistry are considered. The occurrence of macroalgal genera whose distribution is commonly related to estuaries with high nutrient loading is discussed, along with evidence suggesting that the ecophysiological traits of r-selected, ephemeral algae largely contribute to their ecological success and bloom-formation at nutrient-enriched sites.  相似文献   
398.
21世纪中国城市化方式转变与对策研究   总被引:2,自引:0,他引:2  
21世纪之初 ,中国的城市化发展正面临一些新形势 ,必须重新定位城市化战略。本文指出加快城市化步伐 ,重视发展大城市 ,促进城市群的形成与发展 ,有重点地发展小城市 ,是未来中国城市化战略的正确选择  相似文献   
399.
This paper empirically shows how the uncertainty associated to the absence of a mitigation regime which follows the United Nations Framework Convention on Climate Change Kyoto Protocol (UN FCCC Kyoto Protocol) is affecting investments in abatement activities in the EU electricity sector and, thus, future emissions levels. Based on a survey of EU electric utilities, it identifies the most likely post-Kyoto scenarios considered by them and how they are coping with such uncertainty in their investment decisions. It is found that firms react differently to such uncertainty and adopt different strategies to cope with it, diversifying their emissions control activities. Although most companies foresee post-Kyoto compliance regimes with emissions trading systems, they differ in their perceptions of the form that a post-Kyoto regime could take and are, thus, positioning differently to face such regime. The particular features of each company and the country where they operate affect their perception of the uncertainties, their position regarding a possible post-Kyoto regime and their inclination to carry out mitigation activities. Complying with Kyoto (and, eventually, post-Kyoto) targets significantly influences the investment decisions of European electricity companies. Uncertainty about a post-Kyoto regime may already be affecting investments in mitigation activities in the electricity sector. Therefore, significant progress has to be made in the definition of a post-Kyoto regime. It is urgent to define and agree internationally the emissions reduction objectives and the mitigation instruments that will be accepted for compliance, ensuring continuity of the international emissions trading system foreseen in the Kyoto Protocol.
Pablo del RíoEmail:
  相似文献   
400.
以往大部分文献从经济、政治和管理学等角度对“全能政府”与灾害危机之间的关系进行了探讨,过于重视政府角色的扩张,却忽略了非营利部门在灾害救助中的作用。本着社工非营利组织能发挥积极的“补充性(suplementary)”而非“替代性”作用的观点,本文围绕一个核心问题展开,即“社工非营利组织如何根据地震灾害的实际情况制定不同的行为策略,发展出一套组织生存法则”。虽然一些学者对社工组织在灾害救助过程中能否扮演重要角色或功能仍有质疑,但本文认为,社工组织通过“自省”(self-reflection)和“自我观照”(inner-understanding),制定正确的行为策略,就能将灾害危机化为组织发展契机。  相似文献   
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