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701.
植被是陆地表面主要的覆盖物,也是许多地球系统过程的重要变量。人类活动对植被的影响在区域尺度上是显著的。以重庆市为例,使用滑动平均和SG滤波对SPOT/VGT NDVI时间序列数据进行了平滑处理,结合GDP和人口栅格化数据,从时间序列和空间相关场两个方面分析了植被与人类活动因子之间的时空相关性。结果表明,从1998到2005年,植被的分布和生长状况并没有随GDP和人口的持续增加而增加。在时间序列上,植被覆盖与GDP和人口之间总体上呈显著的负相关关系;在空间上,这种相关关系表现出了较强的异质性。空间相关场表明:较强的负相关主要发生在相对发达的主城区周围,反映了快速的经济发展和城市化使得植被面积和生产力降低;然而在偏远的山区,由于经济落后同时植被覆盖较少,出现了正相关。 相似文献
702.
A multiple criteria evaluation of sustainable agricultural development models using AHP 总被引:2,自引:0,他引:2
Selection of the appropriate agricultural development model has become an important issue in Iran. Using data from Fars province
of Iran, the purpose of this paper is to use analytic hierarchy process (AHP) for selecting between the two competing sustainable
agricultural development models, which have been developed based on the general tenets of Ecological Modernization (EM) and
De-Modernization (DM) theories. Farmers, environmentalists, board members of rural cooperative, rural women and experts from
Fars Agricultural (Jehad-e-Keshavarzi) Organization participated in application of AHP to this study. They applied AHP to
determine the priority of DM and EM based sustainable agricultural development models. Each group determined the priority
of the two models for sustainable agricultural development. The findings indicated that ecological criteria i.e. wise use
of resources, environmental protection and product quality are the most important criteria for sustainable agriculture of
Iran, followed by economic criterion employment and social criterion participation. A sensitivity analysis was carried out
to determine the critical factors that affected the priority of alternatives. The results indicated that EM-based sustainable
agricultural development model has a higher priority as the theoretical base of agricultural development of Iran.
Readers should send their comments on this paper to BhaskarNath@aol.com within 3 months of publication of this issue 相似文献
703.
赵文 《中国人口.资源与环境》2007,17(4):140-143
山东省可持续发展试验带建设要解决环境窖量小、人口密度大、支撑经济发展资源消耗大等问题。重点是打破行政区域的行政壁垒.减少经济发展对自然资源的依赖。大力发展高新技术产业。高新技术产品的外部性和高风险性要求政府部门的介入和干预。文章从山东省可持续发展试验带建设存在的市场分割、风险投资机制尚未形成、外向依存度低、高技术人才短缺等问题出发,按照“问题——对策”模式探讨试验带建设中促进可持续发展的金融政策、财税政策等政策选择。 相似文献
704.
Ramiz M. Mamedov Boyukagha N. Mustafayev 《Environment, Development and Sustainability》2007,9(2):131-142
In order to determine the potential for sustainable regional development of the Caspian coastal zone, a study was made for
the Khachmaz–Absheron zone of Azerbaijan. An evaluation was performed to assess the anthropogenic load on landscapes. Using
the 8-point scale offered by Isachenko [2001, Ecological Geography of Russia, Saint Petersburg University Press, Saint Petersburg]
for the indicators of agricultural, industrial, urban and integral anthropogenic loads, we did a preliminary ranking of the
provinces in the Khachmaz–Absheron zone of Azerbaijan for the each indicator taken separately. Vital statistics were used
as a supplementary indicator of environmental conditions in the region. By comparing the data for provinces with each other
and the data on Azerbaijan average, we have classified the provinces into 4 groups according to specific combinations of the
indicators. Each group of provinces has distinctive environmental conditions and features for sustainable development. The
classification makes it possible to develop certain recommendations for the regional sustainable development. Measures to
be implemented within the Azerbaijan State Program on Social and Economic Development of Regions are also discussed. In the
Khachmaz province, production of ecologically pure products is highly recommended. Special attention should be given to the
development of tourism and recreational institutions in the Khachmaz, Khizi and Devechi provinces. Recommendations for these
provinces include further development of industry on the basis of modern safe technologies. The irrigation and drainage networks
should be reconstructed. The reconstruction will make it possible to reduce water loss and to increase the productivity of
agriculture. In the Absheron province, Baku and Sumgait cities environmental systems are overloaded, and so the works at highly
polluting enterprises must be stopped, the enterprises have to be re-equipped (old filters must be changed first of all) or
relocated from the area (a decrease of environmental risk should be in the focus of attention). For improving of air quality,
green areas should increase. There is a need to reduce urban traffic density and to reconstruct highways. Use of old vehicles
must be forbidden or restricted, and transition to environmentally friendly fuel should be supported in every way possible.
It is necessary to bring the waste management system and sanitary landfills up to international standards, and to improve
the water supply and sewerage systems. 相似文献
705.
1IntroductionBohai is the only inland sea in China.It has the highest resource density of all the fourcontinental seas in China.Since the end of the1 970 's,the marine economy around Bohai has seengreat development and the growth rate of the marine industry is up to 2 0 % .It is much higherthan the growth rate of the GDP of this region.The marine economy has greatly contributed tothe development of the economy and society around Bohai.However,since Bohai is an inlandsea,it has the natural … 相似文献
706.
Fabio Orecchini 《Sustainability Science》2007,2(2):245-252
Human society consumes resources that it is not able to reproduce. Human activities are still based on “open cycles,” starting
from a condition of natural environmental balance and reaching an environmental imbalance. The challenging scope of scientific
and technological research towards sustainability appears clear if it is based on this analysis: to find development systems
based on “closed cycles” of resources. The challenging objective of realizing closed cycles leads to a definition of sustainability
that indicates the path to sustainable development, as well as stating the general principle. It also provides a key to the
qualitative measurement of sustainability. This means that the sustainability level of a system can be measured by measuring
its capacity to avoid the consumption of resources. Zero consumption is a necessary condition for sustainability, and brings
about as a side effect the highly desired “zero-waste” result. Materials entering the proposed endless scheme pass through
the process of usefulness without losing their capacity to feed the system again after being used. Thus, the concept of “consumption”
itself is replaced by one of “use” when resources are inserted into closed loops capable of feeding human development. The
application of the closed cycle sustainability criterion particularly displays its feasibility, and a theoretical guiding
role, in the energy sector. Energy vectors such as hydrogen and electricity enable the closure of the energy resources loop
by effectively approaching the objective of “zero consumption” (and the side result of “zero waste”) through already demonstrated
technological solutions. 相似文献
707.
依托清洁生产促进环保产业良性发展 总被引:1,自引:0,他引:1
清洁生产作为一种全新的发展战略,借助各种相关理论和技术,在产品的整个生命周期的各个环节采取预防措施,通过将生产技术、生产过程、经营管理及产品等方面与物流、能量、信息等要素有机结合起来,优化运行凡事,实现最小的环境影响、最少的资源、能源使用,最佳的管理模式以及最优化的经济增长水平。结合现代环保意识的源起与企业实施清洁生产的成功案例,阐述人类要保护赖以生存的地球环境,推动环保产业良性健康发展,为社会经济活动提供必要的资源和能源,实现可持续发展,实施清洁生产是必由之路。 相似文献
708.
京津冀地区面向人居环境之水安全格局初探 总被引:1,自引:0,他引:1
采用文献法对近年京津冀水资源、水环境、水污染、水灾害、水管理等水安全情势进行相关数据分析,从总体上显示出水危机问题和京津冀地区快速城市化发展的关联性.结果表明:1)京津冀城市群必须向节水型社会模式转型;2)建立区域及城市间的协调机制,才能有效克服流域与区域等级的水问题;3)实现京津冀地区水安全格局的治理行动计划网络,提出保护恢复体系、净化循环体系、限制节约体系、调度再造体系、蓄滞防洪减灾体系五大体系. 相似文献
709.
根据北京市环境保护监测中心发布的PM2.5和O3小时质量浓度及气象、卫星遥感数据,分析了2013年7月2日至10日北京典型PM2.5及O3重污染过程的质量浓度特征及在大气边界层过程各个阶段的质量浓度演变.结果表明,北京夏季O3质量浓度先于PM2.5达到峰值,而天气型演变是导致这一现象的主要原因.具体过程为:1)重污染初始阶段,高压天气型利于前体物积累,PM2.5及O3质量浓度升高;2)在反气旋中部,由于各种污染物质量浓度较低,对大气紫外波段辐射的吸收较弱,导致该阶段紫外辐射强,因而加快了O3生成的光化学反应,O3质量浓度最先达到峰值;3)在反气旋后部,随PM2.5质量浓度增加,辐射变弱,因此O3质量浓度增加速度下降,而受高压后部影响,区域内PM2.5经东南风输送通道进入北京,导致北京PM2.5质量浓度相继达到峰值;4)在重污染清除阶段,在北方反气旋前部的冷锋清除作用下,PM2.5及O3质量浓度同时降低至谷值. 相似文献
710.
This paper examines whether foreign aid, together with other economic, social and environmental factors, contributes to sustainable development. It starts with an illustrative theoretical growth model where foreign aid promotes sustainable development by protecting the environment. Using factor analysis and newly developed estimation methods for a dynamic panel data model with endogenous regressors, the empirical section of the paper finds evidence that foreign aid has had a significantly positive influence on sustainable development in aid recipient countries. This effect is very likely to go through channels related to growth and resources as well as a technology channel with respect to energy intensity. This research has important implications for a post‐2015 development framework on international collective action with regard to a sustainable future. 相似文献