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241.
人口、资源、环境是城市和谐发展的三大基本支撑要素。通过计算广州适度人口、验证库兹尼茨曲线、计算生态足迹等,分析了广州人口、资源与环境三者之间的关系。通过分析可以看出,支撑广州城市可持续发展的三大基本要素——人口规模、资源承载力和环境容量基本都已接近峰值,城市发展面临着有史以来的最大压力,而且资源支撑经济社会发展的能力在弱化,但环境总体质量趋向于好转,库兹尼茨曲线正在向其倒U形的右半部分过渡。为实现城市的可持续发展,广州要处理好经济社会发展与人口、资源、环境的关系,更加关注自然资本。  相似文献   
242.
我国城市生活垃圾的处理和发展趋势   总被引:6,自引:0,他引:6  
城市生活垃圾给城市环境造成了严重污染,威胁了城市居民的生存环境和经济、社会的可持续发展。目前,国内采取的垃圾处理技术主要有卫生填埋、焚烧、堆肥等,热解技术由于具有资源回收率高、二次污染小、综合效益好等优点,越来越适合我国中小城市的垃圾处理。垃圾气化技术的研究成为当今世界的热点。此外,我国对垃圾衍生燃料的研究也刚刚起步。为促进城市持续、稳定的发展,提出了垃圾分类收集、分拣、综合利用垃圾处理技术的措施。  相似文献   
243.
多目标规划在产业结构优化中的应用——以秦皇岛市为例   总被引:1,自引:0,他引:1  
秦皇岛是缺水城市,水资源短缺已成为制约经济发展的瓶颈。合理利用水资源对经济发展意义重大。本文采用多目标规划方法,构建了秦皇岛市水资源约束条件下的产业结构优化模型,提出了秦皇岛市产业结构优化方案。  相似文献   
244.
文章分析了浙江省在废纸再生方面的3个典型模式的经验,指出了存在的问题并提出了建议对策。  相似文献   
245.
This paper presents evidence that water restrictions in suburbanizing eastern Massachusetts towns are becoming more common, controlling for climate. We then assess the relationship between these suburban droughts and residential development. Focusing on the suburbs of Boston, seven towns independent of the Boston water supply system were selected to represent differing levels of sprawl-style growth. Water restrictions are becoming more frequent in all of the towns studied, and models demonstrate that restrictions are increasing in duration, independent of climate. Interviews suggest that residential development is playing a central role in this increasing sensitivity to suburban drought, though other factors are also important. Long-term planning and integration of land-use planning and water management emerged as two key paths for attenuating the impacts of development.  相似文献   
246.
Few disputes in the annals of US environmentalism enjoy the pedigree of the conservation-preservation debate. Yet, although many scholars have written extensively on the meaning and history of conservation and preservation in American environmental thought and practice, the resonance of these concepts outside the academic literature has not been sufficiently examined. Given the significance of the ideals of conservation and preservation in the justification of environmental policy and management, however, we believe that a more detailed analysis of the real-world use and understanding of these ideas is needed. In this paper, we describe the results of a qualitative, semantic study of the concepts of conservation and preservation undertaken in the context of the Chattahoochee National Forest (CNF), located in northern Georgia (USA). Thirty in-depth interviews were conducted with scientists and north Georgia residents either interested or involved in the future management of the forest. Respondents were asked to define conservation and preservation in their own words and to indicate which approach they felt was more appropriate for the management of the CNF. Qualitative content analysis was used to elicit a set of recurring themes for each foundational concept. Taken together, these themes help to flesh out the meaning of conservation and preservation for citizens and scientists today, and illustrate the evolving nature of two of the more significant and venerable ideas animating US environmental policy and management.  相似文献   
247.
目前,高校资产管理工作在管理意识、管理方法和管理手段等方面都明显滞后,难以适应高校建设与发展的要求。切实加强高校固定资产管理,就要树立全新的固定资产管理理念,建立科学、合理的保障制度,充分发挥财会、审计部门的重要作用,实现资源共建和共享,同时也要建立可行的资产管理绩效考核制度。  相似文献   
248.
红厚壳野生资源的开发型保护途径分析   总被引:1,自引:0,他引:1  
陈娟  陶忠良 《资源开发与市场》2007,23(11):1029-1031
从红厚壳的生物学特性和具有的油用、药用、材用、观赏、生态保护等多种用途角度出发,针对砍伐严重的状况,提出通过驯化栽培、开发油脂应用范围和加强海岸防护林的设置来保护红厚壳;同时建议政府和科研部门重视并探索红厚壳在中药和油脂加工方面的价值。  相似文献   
249.
ABSTRACT. Planning an optimal system of activities for generating economic goods and services within an existing natural resource capacity is a difficult problem to solve. A mathematical programming model with the capacity to check multiple resource demand and supply compatibility over many time periods was developed for the solution to this type of problem. The characteristics of natural resource supply and the demand of activities were utilized to reduce the number of time periods and to minimize the loss of the dynamic reality of the problem. Reduction in the number of time periods extended the capability of the model to the solution of complex resource planning problems without oversimplification.  相似文献   
250.
ABSTRACT: The Phoenix metropolitan area has a unique combination of circumstances which makes it one of the prime areas in the Nation for waste water reuse. Overriding all of these conditions is the long-term inadequacy of the existing water supplies. The Salt River Valley has a ground water overdraft of about 700,000 acre feet per year. To help alleviate this situation, the Corps of Engineers in conjunction with the MAG 208 is looking at ways to reuse a projected 2020 waste water flow of 340,000 acre feet per year. Reuse options identified include ground water recharge, agricultural irrigation, turf irrigation, recreational lakes, fish and wildlife habitats, and industrial cooling. These look nice on paper but before they can be implemented, some hard questions have to be answered, such as: How acceptable are local treatment plants when 15 years ago there was a major push to eliminate local plants; is the Phoenix area ready for reuse in urban areas; what are people willing to pay for water; who benefits if a city goes to ground water recharge; how much agriculture will be left in the area by 2020? These and other questions must be resolved if reuse is to become a viable option in water resource planning in the Phoenix area. Summary. Large scale reuse of waste water conforms with the national goal of better resource management through recycling. The Phoenix metropolitan area has a unique combination of circumstances which makes it one of the prime areas in the nation for waste water reuse. Some of the most notable conditions are: the existence of a large and rapidly growing urban area which is in the process of planning for future waste water management systems; the existence of agricultural areas which are projected to be farmed well into the future, and the existence of constructed and planned major recreational systems such as Indian Bend Wash which can use recycled waste water; the existence of extensive depleted ground water aquifers; the need for a dependable source for the cooling of the Palo Verde Nuclear reactors; and finally, overriding all of this, the long-term inadequacy of the existing water supplies. Given this, one would expect to find total reuse within the Phoenix metropolitan area. Reuse is taking place with irrigation and nuclear power cooling to the west but there is no long term plan which looks at the Valley as a whole and considers waste water as part of the Valley's water resources. The Corps 208 plan is looking at waste water in this manner but initial analysis shows that although reuse is technically feasible there are many financial, social, institutional, and political questions still to be answered. These include: determining the value of existing diminishing water sources and what people are willing to pay for the next source of water; are people willing to identify priority uses of water for the area so that water of varying quality is put to its highest and best use; will the present institutional boundaries remain to create water-rich and water-poor areas; and will legislation be forthcoming to simplify the complex surface and ground water laws that presently exist? The Corps 208 study will not be able to answer these questions, but the goal at the moment is to identify feasible reuse systems along with decisions the public, owners, agencies, and politicians must make to select and implement them. If some sort of logical process is not developed and public awareness not increased, the chance for a long-term plan to utilize waste water as a major element in the Phoenix area water resource picture, may be missed.  相似文献   
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