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41.
Heavy metal accumulation by plant communities has been studied in different zones of impact of gas field development. The contents of heavy metals in different blocks of plant communities has proved to depend not only on the location of phytocenosis but also on its species composition. Communities dominated by species of the family Poaceae contain smaller amounts of heavy metals than those dominated by species of the family Asteraceae, especially of the genus Artemisia. The order of precedence in the accumulation of heavy metals in different blocks of plant communities has been revealed.  相似文献   
42.
Although stewardship has been widely defined and used in environmental management and planning, there is a dearth of studies that describe how the lay public perceives this concept. A national sample of residents in 14 states who live near DOE nuclear facilities were interviewed to delineate public understanding and awareness of the stewardship program of the U.S. Department of Energy (DOE). This study discusses the findings of the survey and discusses how institutional trust influences public participation and resident’s choices of potential stewards. Almost 40% of the respondents could not define stewardship; those who did, believed that ‘responsibility,’ ‘management,’ and ‘accountability’ are key elements of stewardship. In addition, about a third of the respondents identified Federal groups and the DOE as potential stewards. Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue  相似文献   
43.
现行财税体制下我国耕地资源数量变化的实证研究   总被引:1,自引:0,他引:1  
耕地资源数量变化受到人口、经济等诸多因素的影响,而财税体制是影响耕地资源数量变化的更深屡次原因。通过数量关系的初步观察和作用机理分析说明我国现行财税体制对耕地资源数量变化存在正反两方面作用,总体来看,对耕地资源保护不利。计量结果进一步证实了我国现行财税体制对耕地资源数量变化存在显著影响。揭示了其影响的方向和大小。根据研究结果,文章有针对性地提出了增加地方财政预算收入,合理分配土地出让金比例和科学使用土地出让金等相关政策建议。  相似文献   
44.
浅论国家环境权   总被引:1,自引:0,他引:1  
随着全球环境的日益恶化和公民环保意识的不断增强,环境权理论迅速发展。国家环境权作为一项重要的环境权。在环境法理论逐步变革和权利内涵不断演进的趋势下,已成为法学界研究探讨的重要课题。通过分析国家环境权的国内、国际法律基础。论证了国家环境权的确立。利用类比的方法。阐述了国家环境权与其他宪法权利的不同之处。从权利义务的对等统一和国内国际两个层面。重新归纳了国家环境权的内容。初步构建了国家环境权的基本理论框架。  相似文献   
45.
根据环境意识结构.设计了旅游管理部门环境意识调查问卷。其主要的指标体系包括:旅游环境知识水平、旅游环境态度、旅游环境评价和旅游环境行为四个方面。对指标体系各部分之间以及每一指标部分的每一题目之间的相对重要性进行权重的确定.而且对各部分的每道题目的各个选项予以赋分。基于权重和赋分.结合调查问卷的实际情况,设计了指标体系各部分评价模型和环境意识总体评价模型。以此来计算草原旅游发展中旅游管理部门环境意识水平的综合得分。经过分析得知,旅游管理部门环境意识模式是“环境知识制约型”模式。  相似文献   
46.
Geochemical characteristics of surficial sediments in the Panangad region of Cochin estuary, the largest brackish-water humid ecosystem in the south-west coast of India, were analysed. Temporal variations in nutrient stoichiometry, seasonal characteristics of redox elements Fe and S, and the phosphorus geochemistry were employed for the purpose. The stoichiometric analysis pointed towards autochthonous origin of organic matter, possibility of nitrogen limitation, and allochthonous modification of redox conditions. Seasonal variations were not statistically significant for all the geochemical parameters, whereas significant spatial variations were observed with lower values at sandy stations, suggesting that the texture of the sediments is the main factor influencing the sediment geochemistry. Significant inter-relations between the geochemical parameters also suggest a common control mechanism. Based on these geochemical characteristics, the study region can be effectively categorized into two distinct zones, viz. (1) erosion and transportation and (2) deposition zones.  相似文献   
47.
我国海岸侵蚀灾害及对策   总被引:1,自引:0,他引:1  
赵全基 《灾害学》1992,7(4):39-42
文章通过大量实际资料展现了我国海岸侵蚀灾害的严重性;从入海泥沙、人类活动、地面沉降、海岸特性、海平面上升等方面分析了造成海岸侵蚀的原因;提出了一系列防治海岸侵蚀灾害的对策。  相似文献   
48.
农业生产地域分工与农产品专业化生产是使农业从自然经济阶段向以市场为导向的商品农产品生产转变的一个标志。本文在分析该区农业布局现状及其存在问题的基础上,提出了农业总体布局的设想与不同类型地域农业开发的主攻方向与对策,并对市场经济体制下粮食、棉花、猪、禽、水产品等农产品生产基地的地域选择、建设规模与技术措施等进行了探讨。  相似文献   
49.
本文简要介绍区域性“减灾十年初步规划”编制的一般原则,包括规划编制的意义、目的、编制顺序和规划应注意的几个方面,并提出规划成果的实施意见。可供各地编制规划时参考。  相似文献   
50.
/ Why are some environmental risks distributed disproportionately in the neighborhoods of the minorities and the poor? A hypothesis was proposed in a recent study that market dynamics contributed to the current environmental inequity. That is, locally unwanted land uses (LULUs) make the host communities home to more poor people and people of color. This hypothesis was allegedly supported by a Houston case study, whereby its author analyzed the postsiting changes of the socioeconomic characteristics of the neighborhoods surrounding solid waste facilities. I argue that such an analysis of postsiting changes alone is insufficient to test the causation hypothesis. Instead, I propose a conceptual framework for analysis of environmental equity dynamics and causation. I suggest that the presiting neighborhood dynamics and the characteristics of control neighborhoods be analyzed as the first test for the causation hypothesis. Furthermore, I present theories of neighborhood change and then examine alternative hypotheses that these theories offer for explaining neighborhood changes and for the roles of LULUs in neighborhood changes. These alternative hypotheses should be examined when analyzing the relationship between LULUs and neighborhood changes in a metropolitan area. Using this framework of analysis, I revisited the Houston case. First, I found no evidence that provided support for the hypothesis that the presence of LULUs made the neighborhoods home to more blacks and poor people, contrary to the conclusion made by the previous study. Second, I examined alternative hypotheses for explaining neighborhood changes-invasion-succession, other push forces, and neighborhood life-cycle; the former two might offer better explanation.KEY WORDS: Environmental equity and justice; Locally unwanted lane uses; Siting; Market dynamics; Invasion-succession; Neighborhood changes  相似文献   
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