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991.
Since the establishment, following World War II, of the World System, by which the affluent industrialized countries established various international assistance agencies (including the multilateral development banks, UN affiliates, and Bilaterals), these assistance agencies have invested very large sums in helping finance planning and construction of community sewerage and water supply facilities in the developing countries. However, much of this large investment has been ineffective and wasted, primarily because of the lack of understanding by the staff of the assistance agencies that the design criteria for the facilities must be modified to suit the socio-economic status of the developing country. The developing countries are relatively very poor in terms of available finances, hence cannot afford to emulate Western environmental standards and design practices, especially as related to operation and maintenance, hence much simpler approaches must be used. Experiences in several Asian countries are discussed, and a recommendation is made on how to go about resolving this problem. 相似文献
992.
Assessing Biological Integrity Using Freshwater Fish and Decapod Habitat Selection Functions 总被引:2,自引:0,他引:2
Comparison between the number of taxa observed and the number expected in the absence of human impact is an easily understood and ecologically meaningful measure of biological integrity. This approach has been successfully applied to the assessment of the biological quality of flowing water sites using macroinvertebrates with the river invertebrate and classification system (RIVPACS) and its derivatives. In this paper, we develop a method similar to the RIVPACS predictive model approach to assess biological integrity at flowing-water sites using freshwater fish and decapod assemblages. We extend the RIVPACS approach by avoiding the biotic classification step and model each of the individual species separately. These assemblages were sampled at 118 least impacted (reference) sites in the Auckland region, New Zealand. Individual discriminant models based on the presence or absence of the 12 most common fish and decapod species were developed. Using the models, predictions were made using environmental measures at new sites to yield the probability of the capture of each of the 12 species, and these were combined to predict the assemblage expected at sites. The expected assemblage was compared to that observed using an observed over expected ratio (O/E). The models were evaluated using a number of internal tests including jackknifing, data partitioning, and the degree to which O/E values differed between reference sites and a set of sites perceived to be impaired by human impacts. 相似文献
993.
景观生态学在建设项目生态环境影响评价中的应用 总被引:13,自引:0,他引:13
景观生态学目前是国家环境保护总局《非污染生态影响评价技术导则》引入的概念框架和理论方法。本文通过景观生态学在不同性质建设项目中的运用分析,进行了一定的尝试,更加希望在今后建设项目生态环境影响评价工作中得到修正和完善。 相似文献
994.
BACKGROUND: Safety teams have become a popular means to recognize and prevent injuries in the workplace. In fact, organizations, such as OSHA, NIOSH, NIEHS, DOE, and the Ohio BWC, not only encourage safety teams, but have implemented them in their organizations. However, safety teams may not be legal as defined by NLRB Act Sections 2(5) and 8(a)(2). OBJECTIVE: To determine whether safety teams are illegal labor organizations. METHODS: A review of government regulations, safety programs, and safety teams was performed to create a framework of what types of safety programs/regulations are requested and/or required by a variety of government agencies. Next, these requirements were compared to existing case law on illegal labor organizations as defined by the NLRB. RESULTS: Most safety teams and programs, even those implemented by the Federal Government, are illegal labor organizations as defined by NLRB Act Sections 2(5) and 8(a)(2). CONCLUSIONS: The Federal Government needs to amend existing legislation and develop a revision of the NLRB Act that would allow safety teams to function legally in organizations without having to meet intrusive, constricting guidelines that may inhibit the value of safety teams. IMPACT ON INDUSTRY: Organizations must be aware that safety teams may be valuable in reducing job-related accidents and injuries but they may be illegal labor organizations. 相似文献
995.
Human impacts on the stream-groundwater exchange zone 总被引:13,自引:0,他引:13
Hancock PJ 《Environmental management》2002,29(6):763-781
Active exchanges of water and dissolved material between the stream and groundwater in many porous sand- and gravel-bed rivers
create a dynamic ecotone called the hyporheic zone. Because it lies between two heavily exploited freshwater resources—rivers
and groundwater—the hyporheic zone is vulnerable to impacts coming to it through both of these habitats. This review focuses
on the direct and indirect effects of human activity on ecosystem functions of the hyporheic zone. River regulation, mining,
agriculture, urban, and industrial activities all have the potential to impair interstitial bacterial and invertebrate biota
and disrupt the hydrological connections between the hyporheic zone and stream, groundwater, riparian, and floodplain ecosystems.
Until recently, our scientific ignorance of hyporheic processes has perhaps excused the inclusion of this ecotone in river
management policy. However, this no longer is the case as we become increasingly aware of the central role that the hyporheic
zone plays in the maintenance of water quality and as a habitat and refuge for fauna. To fully understand the impacts of human
activity on the hyporheic zone, river managers need to work with scientists to conduct long-term studies over large stretches
of river. River rehabilitation and protection strategies need to prevent the degradation of linkages between the hyporheic
zone and surrounding habitats while ensuring that it remains isolated from toxicants. Strategies that prevent anthropogenic
restriction of exchanges may include the periodic release of environmental flows to flush silt and reoxygenate sediments,
maintenance of riparian buffers, effective land use practices, and suitable groundwater and surface water extraction policies. 相似文献
996.
River systems as providers of goods and services: a basis for comparing desired and undesired effects of large dam projects 总被引:3,自引:0,他引:3
Brismar A 《Environmental management》2002,29(5):598-609
In developing countries, large dam projects continue to be launched, primarily to secure a time-stable freshwater supply and
to generate hydropower. Meanwhile, calls for environmentally sustainable development put pressure on the dam-building industry
to integrate ecological concerns in project planning and decision-making. Such integration requires environmental impact statements
(EISs) that can communicate the societal implications of the ecological effects in terms that are understandable and useful
to planners and decision-makers.
The purpose of this study is to develop a basic framework for assessing the societal implications of the river ecological
effects expected of a proposed large dam project. The aim is to facilitate a comparison of desired and potential undesired
effects on-site and downstream. The study involves two main tasks: to identify key river goods and services that a river system
may provide, and to analyze how the implementation of a large dam project may alter the on-site capacity and downstream potentials
to derive river goods and services from the river system.
Three river goods and six river services are identified. River goods are defined as extractable partly man-made products and
river services as naturally sustained processes. By four main types of flow manipulations, a large dam project improves the
on-site capacity to derive desired river goods, but simultaneously threatens the provision of desirable river goods and services
downstream. However, by adjusting the site, design, and operational schedule of the proposed dam project, undesirable effects
on river goods and services can be minimized. 相似文献
997.
Public involvement is recognized by legislators, practitioners, academics, nongovernment organizations and, most importantly,
affected communities, as a fundamental component of environmental assessment (EA) processes. Experience with public involvement
in EA has proven, however, that despite good intentions, there are formidable barriers to participation. This paper examines
this issue, largely through a case study of a new Can$120 million hog processing facility in Brandon, Canada. Primary data
were collected in three phases, using multiple methodological techniques, including document review, qualitative interviews,
and a mail questionnaire. Results included a diverse list of barriers to involvement, grouped into two primary categories:
structural and individual. A significant structural barrier was a belief that becoming involved would not make a difference
as the ultimate decision in the case was a foregone conclusion. An important individual barrier was that people did not know
about the EA. Finally, the results indicated that lack of interest was not an important reason for nonparticipation. 相似文献
998.
999.
Veiga LH Koifman S Melo VP Sachet I Amaral EC 《Journal of environmental radioactivity》2003,70(3):161-176
This paper aims to present an assessment of the environmental radiological exposure at a Brazilian area of high natural radiation and discusses the indoor radon exposure risk. A survey of inhabitant exposures arising from the inhalation of radon progeny and external gamma exposure was conducted in urban and rural areas of the Po?os de Caldas Plateau, which is recognized worldwide as a high natural radiation region. The results of this survey indicated that highest radiation exposure was restricted to the rural area of Po?os de Caldas. The radiation exposure in urban locations was quite similar to the values observed in normal background areas in some Brazilian counties. By the application of a constant relative risk model, an additional 20% in the lifetime risk of lung cancer mortality due to the exposure to radon progeny was estimated at Po?os de Caldas. It was also estimated that 16% of all lung cancer deaths at Po?os de Caldas county could be attributable to radon exposure. 相似文献
1000.
Methods for life cycle assessment of products (LCA) are most often based on the general prevention principle, as opposed to the risk minimization principle. Here, the desirability and feasibility of a combined approach are discussed, along with the conditions for elaboration in the framework of LCA methodology, and the consequences for LCA practice. A combined approach provides a separate assessment of above and below threshold pollution, offering the possibility to combat above threshold impacts with priority. Spatial differentiation in fate, exposure, and effect modelling is identified to play a central role in the implementation. The collection of region-specific data turns out to be the most elaborate requirement for the implementation in both methodology and practice. A methodological framework for the construction of characterization factors is provided. Along with spatial differentiation of existing parameters, two newly introduced spatial parameters play a key role: the sensitivity factor and the threshold factor. The practicability of the proposed procedure is illustrated by an example of its application. Providing a reasonable data availability, the development of separate LCA characterization factors for the respective assessment of pollution levels above and below environmental threshold values seems to be a feasible task that may add to LCA credibility. 相似文献