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951.
通过建立和完善空气中有机污染物的分析方法,对徐州市区空气中的有机污染物开展了全面详细的探查,弄清了市区空气中有机污染物的污染现状及时空变化规律,填补了徐州市空气监测数据中的有机污染物的空白,为开展空气有机污染物的调查和监测奠定了一定的基础。  相似文献   
952.
随着社会的进步,人民生活水平的提高,人们运用法律武器保护自己的权益已逐渐成为常识.病人对自身健康的保护意识、经济意识也在不断增强,故医疗纠纷时有发生.一旦发生医疗纠纷,医院所消耗的人力、财力、物力、精力是无法估量的.笔者从医疗纠纷的预防和处理两方面进行分析与阐述,强调医护人员提高服务意识、法律意识、预防为主意识的重要性,从而从根本上防止医疗纠纷的发生.参2.  相似文献   
953.
论环境安全问题   总被引:33,自引:0,他引:33  
将环境安全分为生产技术性的环境安全和社会政治性的环境安全两类。认为广义的环境安全是指人类赖以生存发展的环境处于一种不受污染和破坏的安全状态,或说人类和世界处于一种不受环境污染和环境破坏的危害的良好状态,它表示自然生态环境和人类生态意义上的生存和发展的风险大小。分析了当代环境安全问题的严重性和主要表现,包括劳动环境。生活环境和生态环境的安全问题,以及环境问题在传统的国家安全和军事活动领域的反映,认为环境安全是可持续发展观的一个核心观点;可持续发展要求满足全体人民的基本需要,而维护环境安全正是人们的一种基本需要,分析了外国,国际社会和中国对环境安全问题的法律控制概况。介绍了一些重要领域的环境安全法观。  相似文献   
954.
周红 《四川环境》2001,20(2):77-78
针对目前环境执法的现状及存在的问题,从提高环境意识,完善执法体制,坚持依法行政,加强队伍建设等方面,阐明了作者的观点,以期引起各方的关注。  相似文献   
955.
本文首先对环境技术引进的社会背景及其相关法律问题作了简要说明,对环境技术引进的一般法律管制进行了分析,较为深入的阐述了对环境技术引进进行环境活动规制的必要性,并提出了对环境技术引进进行环境法律规制的基本原则及基本制度。  相似文献   
956.
ABSTRACT: We evaluated changes in channel habitat distributions, particle‐size distributions of bed material, and stream temperatures in a total of 15 first‐or second‐order streams within and nearby four planned commercial timber harvest units prior to and following timber harvest. Four of the 15 stream basins were not harvested, and these streams served as references. Three streams were cut with unthinned riparian buffers; one was cut with a partial buffer; one was cut with a buffer of non‐merchantable trees; and the remaining six basins were clearcut to the channel edge. In the clearcut streams, logging debris covered or buried 98 percent of the channel length to an average depth of 0.94 meters. The slash trapped fine sediment in the channel by inhibiting fluvial transport, and the average percentage of fines increased from 12 percent to 44 percent. The trees along buffered streams served as a fence to keep out logging debris during the first summer following timber harvest. Particle size distributions and habitat distributions in the buffered and reference streams were largely unchanged from the pre‐harvest to post‐harvest surveys. The debris that buried the clearcut streams effectively shaded most of these streams and protected them from temperature increases. These surveys have documented immediate channel changes due to timber harvest, but channel conditions will evolve over time as the slash decays and becomes redistributed and as new vegetation develops on the channel margins.  相似文献   
957.
ABSTRACT: The shape of a river channel is linked to surrounding land use through interacting hydrologic and geologic processes. This study analyzes the relationship between the change in near‐stream land use and the shape of the adjacent river channel over time. Three watersheds in the foothills of the Venezuelan Andes that have experienced differing degrees of development were studied to determine river channel width, sinuosity, and position relative to surrounding land use. Change in land use over time was obtained from multiple‐date aerial photographs (1946 and 1980) referenced to 1996 Landsat Thematic Mapper (TM) satellite imagery, and verified by field inspection. Measurements of land‐use type and amount and river channel morphology from the two dates were made using geographic information system (GIS) methods. The three watersheds differed in the extent of deforestation, the location of remaining forested land, and how much land‐use change had already occurred by 1946. Change in river channel morphology was greatest at the most deforested sites. Valley shape and channel constraint also had a discernible effect on change in channel morphology. This study introduces a method for analyzing change in coupled terrestrial‐aquatic systems based on multiple‐date, remotely sensed data and GIS analysis of spatial properties. The results document human impacts on river channels through a comparison of multiple watersheds over a 35‐year time interval.  相似文献   
958.
ABSTRACT: Riparian areas interact with aquatic and upland conditions and therefore help determine the degree of functionality (streambank stability, shade, sediment, and debris filtering) found in a watershed or catchment. Thus, conditions in riparian areas exert significant influence on water quality. Physical and biological factors (biophysical determinants) that influence these conditions and determine long‐term site ecology include topographic variables, geology, climate, soil texture, and others. These conditions are further modified by management infrastructure (roads, dikes, etc.). Our objective was to develop a system for evaluating site condition in relation to site capability. Since biophysical determinants and infrastructure interact with water quality, our first task was to acquire data concerning the spatial distribution of biophysical determinants and infrastructure constraints and to import them into a GIS system where they could be managed and processed. To expedite analysis, determinants and infrastructure constraints were placed into a hierarchy capable of isolating various site capability types. The hierarchy was designed to incorporate multiscale effects. Site capability areas are georeferenced in this process thereby enabling efficient monitoring and providing a way to focus management on those areas needing improvement. Study tasks included: (1) landscape characterization and hierarchy selection, (2) field assessment, (3) information management and data mining, and (4) information interpretation and adaptive management. This approach appears to be an effective way to isolate general ripananstandardsmaycon site conditions, to provide indications about water quality, and to create strategies necessary for alleviating water quality problems.  相似文献   
959.
ABSTRACT: New Zealand is one of the first countries in the world to enshrine the concept of watershed management in law, through institutional arrangements and the Resource Management Act of 1991 ‐ a law constructed on a watershed management legacy begun in 1941. This paper outlines the development of New Zealand's Resource Management Act (as it applies to water management) and the lessons that have been learned in its implementation.  相似文献   
960.
Conflicts between protected-area managers and local people are common, but the drivers of conflict are rarely analyzed. This limits opportunities to identify strategies that reduce conflict and the magnitude of resulting threats to conservation. Integrated conservation and development (ICD) was adopted at Bwindi Impenetrable Forest, Uganda, to reduce conflict during gazettement of the national park, but the success of this approach remains contested. We retrieved documents of conflict written by park staff and local people from 1986 through 2000 (before, during, and after gazettement). We extracted data on 48 incidences of violent conflict and categorized them by gazettement period, area, instigator, and type to undertake a historical analysis of the triggers of violent conflict at Bwindi. Before and during gazettement, local villagers instigated most of the conflict incidents when law-enforcement efforts sought to halt commercial activities within Bwindi. No conflict arose from the arrest of villagers collecting subsistence resources during these periods. After gazettement, prohibitions on commercial activities continued to drive conflict even though villagers collecting subsistence resources were arrested more frequently than before gazettement, and local attitudes toward the park had improved following receipt of ICD benefits. Law-enforcement efforts targeted commercial activities to reduce this threat to Bwindi's mountain gorillas (Gorilla beringei beringei), although the activities remained important income sources for people in villages near Bwindi. Losing commercial income following gazettement therefore appeared to be their primary motivation for instigating conflict with park rangers. Prohibitions on subsistence resource use triggered conflict less often. Our use of typologies for a multivariate conflict analysis demonstrates that by identifying differences between effects of conservation as drivers of conflict, conflict analysis can enable a more strategic deployment of conflict-resolution measures that could further conservation efforts. At Bwindi targeting ICD toward individuals who lost benefits from commercial activities may strengthen the role of ICD in conflict resolution and conservation.  相似文献   
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