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981.
982.
江苏所处的中国东部被当代横贯欧亚的北西西向环球螺旋形扭转断裂带(其东段即大别—舟山断裂)分割为南部的褶皱山带隆升区和北部的沉降区。软流圈从太平洋方向面楔入北部区,使该区岩石圈减薄,陆壳向海洋伸展、离裂,产生郯庐断裂等具有直扭性质的近南北向软流(及地幔)底辟,并伴随有多层水平拆离面,所见为高导低速的水平破裂带。绝大多数地震沿着其中埋深15km(±5km)的第一水平破裂带发生,使北部区成面积性地震区。结合高压物性实验所得的岩石微破裂规律(…分割—错位—嵌合—再分割…)判断得知,水平破裂带中的膨胀增厚部分的流体处在超压状态而成为储能体,在陆壳伸展运动中会突然释放能量而诱发地震。因此,根据已有实际分析认为:强震和频震区的发展的必要条件是软流楔入和陆壳伸展,而其充分条件是储能体在软流冲击和增温效应下的爆裂或突然塌缩事件。据此可根据软流运动和岩石圈结构预测未来震中,建立中、长期预报甚至短临预报的监控系统  相似文献   
983.
传统工业生产方式在可持续发展背景下面临严峻挑战,清洁生产应而生,它是持续利用资源,减少工业污染,保护环境的根本措施,本文就清洁生产在中国示范推广所产生的经济,社会及环境效益进行了综合论述。  相似文献   
984.
Abstract:  The traditional environmental Kuznets curve (EKC) hypothesis postulates that environmental degradation follows an inverted U-shaped relationship with gross domestic product (GDP) per capita. We tested the EKC hypothesis with bird populations in 5 different habitats as environmental quality indicators. Because birds are considered environmental goods, for them the EKC hypothesis would instead be associated with a U-shaped relationship between bird populations and GDP per capita. In keeping with the literature, we included other variables in the analysis—namely, human population density and time index variables (the latter variable captured the impact of persistent and exogenous climate and/or policy changes on bird populations over time). Using data from 9 Canadian provinces gathered over 37 years, we used a generalized least-squares regression for each bird habitat type, which accounted for the panel structure of the data, the cross-sectional dependence across provinces in the residuals, heteroskedasticity, and fixed- or random-effect specifications of the models. We found evidence that supports the EKC hypothesis for 3 of the 5 bird population habitat types. In addition, the relationship between human population density and the different bird populations varied, which emphasizes the complex nature of the impact that human populations have on the environment. The relationship between the time-index variable and the different bird populations also varied, which indicates there are other persistent and significant influences on bird populations over time. Overall our EKC results were consistent with those found for threatened bird species, indicating that economic prosperity does indeed act to benefit some bird populations.  相似文献   
985.
Abstract: The conflict between economic growth and biodiversity conservation is understood in portions of academia and sometimes acknowledged in political circles. Nevertheless, there is not a unified response. In political and policy circles, the environmental Kuznets curve (EKC) is posited to solve the conflict between economic growth and environmental protection. In academia, however, the EKC has been deemed fallacious in macroeconomic scenarios and largely irrelevant to biodiversity. A more compelling response to the conflict is that it may be resolved with technological progress. Herein I review the conflict between economic growth and biodiversity conservation in the absence of technological progress, explore the prospects for technological progress to reconcile that conflict, and provide linguistic suggestions for describing the relationships among economic growth, technological progress, and biodiversity conservation. The conflict between economic growth and biodiversity conservation is based on the first two laws of thermodynamics and principles of ecology such as trophic levels and competitive exclusion. In this biophysical context, the human economy grows at the competitive exclusion of nonhuman species in the aggregate. Reconciling the conflict via technological progress has not occurred and is infeasible because of the tight linkage between technological progress and economic growth at current levels of technology. Surplus production in existing economic sectors is required for conducting the research and development necessary for bringing new technologies to market. Technological regimes also reflect macroeconomic goals, and if the goal is economic growth, reconciliatory technologies are less likely to be developed. As the economy grows, the loss of biodiversity may be partly mitigated with end‐use innovation that increases technical efficiency, but this type of technological progress requires policies that are unlikely if the conflict between economic growth and biodiversity conservation (and other aspects of environmental protection) is not acknowledged.  相似文献   
986.
改革开放以来,我国城市化过程出现快速发展时期,特别是长江下游地区(长江三角洲及其周边地区),由于人口与产业不断集聚,重大基础设施项目投资加大,道路网密度增加,开发区扩大,使得城市空间迭加扩展,造成了严重的水土资源利用失衡,生态环境日趋恶化,使本地区城市发展出现了许多新问题。以长江下游地区为例,对本区城市化过程中有关水土资源环境恶化、水污染增加、土地资源流失,以及城镇化速度过快的情况,作了深入分析论证,同时对长江下游地区水土资源合理开发利用与保护提出了新的思维、新的方法措施,特别是对如何加强长三角地区水质环境的整治提出了4点切实可行的办法与措施,为本地区的经济发展与生态安全提供科学依据.  相似文献   
987.
南京市处于长江流域下游,是我国重要的农业生产基地,也是全国经济发达地区之一。它既有近郊的蔬菜生产,又有远郊的粮食作物种植,农田生态类型与农、牧、副的复合生态类型多种多样,而且其生产潜力很大。本文对南京市郊生态系统的建设进行分析研究,并着重探讨生态系统建设模式及土地合理利用,为建立合理的南京市郊区农业生态系统提供依据。  相似文献   
988.
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   
989.
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   
990.
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   
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