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691.
政府承担生态环境损害赔偿责任的理论基础是政府对环境质量负责,政府对环境质量负责的实质是政府作为公共环境的管理者和控制者对维护公共环境利益所负担的安全保障义务。根据政府的环境安全保障义务,政府承担生态环境损害赔偿责任应以过错推定为归责原则,责任构成的核心是政府负有其职责范围内特定的环境安全保障义务,因未尽环境安全保障义务间接引发生态环境损害。由于政府未尽环境安全保障义务的行为并非直接也并不必然导致生态环境损害,所以政府一般仅根据自身行为的可责性及其程度对生态环境损害承担补充性的赔偿责任,只有在特殊情况下才承担连带赔偿责任,在政府不负有特定环境安全保障义务的情况下政府不承担赔偿责任。 相似文献
692.
聂立民 《防灾科技学院学报》2006,8(3):96-97
共同做好防震减灾工作,政府各职能部门要各司其职,各负其责仅靠领导重视及部门之间的密切配合还不够,必须用相应的制度做保证。还要通过不断的加强宣传,在各级领导的思想中树立起“经济建设与防震减灾工作同等重要”的观念。 相似文献
693.
Alexia Prskawetz Alessandra Gragnani Gustav Feichtinger 《Environmental Modeling and Assessment》2003,8(1):35-45
Within the framework of a general equilibrium model we study the long-run dynamics of resources and population if the growth rate of resources and population and the share of labor devoted to production are adversely affected by resource scarcity. Our results show that sustainability, i.e. a positive value of resources and population in the long run, essentially depends on the level of per capita resources at which these feedback mechanisms become active. A detailed bifurcation analysis evidences the richness of possible long-run dynamics. 相似文献
694.
/ Implemented in the context of a long history ofintense public debate, forestry practices applied on private forest land areregulated in some form by 38 states. State regulatory activities can involvemany agencies implementing numerous regulatory laws, a single forestry agencyadministering a comprehensive regulatory program, or a combination of thetwo. Regulatory programs are designed to protect resources such as soils,water, wildlife, and scenic beauty. Program administration often involvesrule promulgation, harvest plan reviews, coordination of interagency reviews,and pre- and postharvest on-site inspections. Forest practice rules usuallyfocus on reforestation, forest roads, harvest procedures, and wildlifehabitat protection. Emerging regulatory trends include growth of multiagencyregulatory authority and associated jurisdictional conflicts, increasedtendencies to narrowly specify standards in statutes and rules, emergence ofcontingent regulations, growing sensitivity to processes enabling theadoption of new forest practice technologies and an ability to addresscumulative effects, interest in collaborative rule-making stemming fromheightened concern over legalization of administration processes, and growingconcern over the constitutional foundations for regulatory programs and thegovernment and private sector cost of implementing such programs.KEY WORDS: Ecosystem management; Forestry practices; Private landowners;Regulatory programs; State government 相似文献
695.
顾及空间自相关性的高分遥感影像中建设用地的变化检测 总被引:2,自引:1,他引:1
在中国城市化的进程中,建设用地常常连片分布,其开发在空间上具有明显的聚集性,表现出较强的空间自相关性,这在高空间分辨率的遥感图像中更加明显。基于2016年、2017年两期南京市域内的北京2号3.2 m多光谱遥感图像,对比分析了引入变化向量的空间自相关指数作为图像特征后建设用地遥感变化检测的性能。首先提取遥感图像光谱变化向量的局部G指数、Moran's I和Geary's C三个典型空间自相关指数,然后确定适用于变化检测的最优空间间隔(Lag)范围和最优自相关指数。结果表明:(1)光谱变化向量在空间上具有显著的正相关性。(2)全局Moran's I和半方差函数相结合可以确定最优的Lag范围。(3)在光谱变化向量的基础上加入局部G指数和局部Moran's I能够提高检测精度,F1分数表明前者优于后者。(4)在光谱变化向量的基础上加入最优Lag范围内的局部G指数作为附加图像特征,F1分数比只使用光谱变化向量提高了20%以上。融合空间自相关信息,特别是多尺度局部G指数作为遥感图像特征可有效地提高连片区域建设用地的变化检测精度。 相似文献
696.
The present study was undertaken to explore possibilities to judge survey quality on basis of a limited and restricted number of a-priori observations. Here, quality is defined as the ratio between survey and local variance (signal-to-noiseratio). The results indicate that the presented surveys do not permit such judgement. Furthermore, the discussion alsosuggests that the 5-fold local sampling strategies do not merit any sound judgement in about 10% of all cases.The results further imply that surveys will benefit from procedures, controls and approaches in sampling and sample handling, to assess both average, variance and the nature of the distribution of elemental concentrations in local sites. This reasoning is compatible with the idea of the site as a basic homogeneous survey unit, which is implicitly and conceptually underlying any survey performed. 相似文献
697.
Community Production Practices and Desertification in the Sahelo-Sudanian Region of Cameroon at the Turn of the Millennium 总被引:2,自引:0,他引:2
Pamo ET 《Environmental monitoring and assessment》2004,99(1-3):197-210
The Sahelo-Sudanian region of Cameroon extends over 10 million hectares. Varied flora and soil types, a complex mosaic of
vegetation and plant communities and a diversified wild animal population are the major natural resources of this region.
Desertification in the region can be related to two major known causes: a. short or long-term drought due to short-term or
long-term climatic trends toward aridity; b. human activities which degrade the biological environment. Globally, humans generally
have less effect on desertification than climatic change in the short run. The only strategy to fight against this situation
particularly in the developing countries is to withdraw populations from the areas and to settle them elsewhere. However,
most local or regional desertification processes in general, and in the Sahelo-Sudanian region in particular, are due to the
misuse or unsound exploitation of natural resources by humans and their animals. Often, comprehension of the complexity of
even small interactions between parameters affecting our local environment remains limited. Poor economic assessments of the
long-term benefits of proper natural resource conservation and management increase the extent of the exploitation, in turn
increasing the degradation process. Yet ecologically sound management of natural resources integrating indigenous knowledge
and basic population interest and concern can secure restoration in several areas and sustained productivity of Sahelo-Sudanian
lands. 相似文献
698.
培养安全工程专业人才应与地方经济相适应 总被引:1,自引:3,他引:1
安全工程专业人才培养的模式,已从原有的以行业背景为主的安全技术人才的培养向现有的以技术为基础的通用安全管理人才的培养方向转变。由于各地经济的模式及工业基础的差异,安全事故发生的特点也不相同,对人才的需求也有所区别。尤其是安全工程专业人才,也成为经济发展需求的紧缺人力资源,各地争相举办安全工程及其相关专业,使安全工程专业教育有了新的发展。笔者提出高校应充分利用现有教育资源,采用“基础型”、“安全系统型”的宽口径的教育方式,在进入专业课时,开设多个专业方向的培养模式,增加学生就业渠道,以适应地方经济的发展。 相似文献
699.
This paper describes a method for predicting local scour around bridge piers using an artificial neural network (ANN). Methods for selecting input variables, calibrations of network control parameters, learning process, and verifications are also discussed. The ANN model trained by laboratory data is applied to both laboratory and field measurements. The results illustrate that the ANN model can be used to predict local scour in the laboratories and in the field better than other empirical relationships that are currently in use. A parameter study is also carried out to investigate the importance of each input variable as reflected in data. 相似文献
700.