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51.
This journal first reported on the U.S. EPA's Brownfields Initiative in the summer 1995 edition of Remediation. At that time, the initiative was only about 15 months old, most of the state programs were in proposal stages, and little federal legislation addressing brownfields had been proposed. Today, brownfields has become such a common term that almost every environmental professional is familiar with it. The EPA has placed extremely high priority on the Brownfields Initiative and it has become a politically hot issue. This article provides an update on the current status of EPA's Brownfields program and also discusses recent legislation proposed by Congress to promote brownfields redevelopment. © 2001 John Wiley & Sons, Inc.  相似文献   
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Summary The first-laid eggs of Eudyptes penguins are much smaller than second eggs, generally hatch later, and experience greater mortality, features that characterize a brood reduction system unlike that of any other avian group. Hypotheses that (1) first-egg mortality is incidental to aggressive behavior by nesting birds and (2) hatching asynchrony is created by preferential egg treatment during incubation were tested in a colony of Fiordland crested penguins (E. pachyrhynchus). Neither hypothesis was supported. Although first eggs experienced greater mortality than second eggs, losses were not associated with aggressive behavior or the degree of nest crowding. First eggs hatched later than second eggs and were found more often in the anterior (previously assumed inferior) nest position. However, that position was not thermally disadvantaged, nor were lower temperatures consistently recorded from the smaller eggs. Parental brood patches did not form until after the first egg was laid; this delay may be a causal factor in the evolution of the unique reversal in eudyptid egg dimorphism.  相似文献   
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A 1988 survey, funded by the US Environmental Protection Agency (EPA) and conducted by the American Fisheries Society, identified the need to standardize the approaches for evaluating risks and developing fish consumption advisories that are comparable across different jurisdictions. A major tool for evaluating the progress in developing such nationally consistent information is EPA??s web-based National Listing of Fish Advisories (NLFA) database, which has archived fish advisory information since 1993. The NLFA comprises both a database and Geographic Information System mapping components that are implemented using the National Hydrography Dataset (NHD). EPA and the US Geological Survey have developed an enhanced NHD product (NHDPlus) that is applied to define an interstate waters framework for the conterminous USA. This NHDPlus-based framework provides an efficient watershed-oriented approach for identifying interstate advisories from NLFA. We provide summaries of (1) the degree of consistency documented for inland waters where states have issued advisories for shared interstate NHD reaches and (2) the patterns for interstate advisories organized according to the ecoregions developed for EPA??s Wadeable Streams Assessment. Approaches are also discussed for addressing interstate consistency issues for fish advisories in coastal waters making use of the NHDPlus combined with other nationally consistent frameworks, such as the 12-digit hydrologic unit code subwatersheds in the Watershed Boundary Dataset. Probability survey methods are recommended as a way to promote increased interjurisdictional consistency in the development of the monitoring and risk assessment conclusions reflected in NLFA, as well as in other EPA water quality-based programs.  相似文献   
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The production of timber from native forests is presently one of the most controversial land management issues in Australia. Part of this controversy results from the potential impacts of forestry practices on forest-dependent fauna, particularly those that are rare and endangered, such as Leadbeater's Possum Gymnobelideus leadbeateri McCoy, in the forests of central Victoria, south-eastern Australia. A significant proportion of the highly limited distribution of this species overlaps with some of the most valuable wood production forests in Australia within which extensive clearfelling operations are employed to produce timber and pulpwood. These operations can destroy the habitat of G. leadbeateri. The Victoria government agency that is responsible for forest and wildlife management has devised a forest zoning system as part of the management strategies to conserve G. leadbeateri within timber production areas. This is designed to partition the forest into three types of areas: (1) where the conservation of G. leadbeateri is a priority, (2) where wood production is a priority, and, (3) where both land uses are a joint priority. The classification of areas of forest where the conservation of G. leadbeateri is the primary land use is based on an understanding of the habitat requirements of the species. The results of recent field studies, where statistical models of the habitat requirements of G. leadbeateri have been developed and their performance subsequently tested using a new dataset, highlights the need for a new basis to guide the classification of areas for the conservation of the species within wood production forests. We describe a method for devising a forest management zoning system that is based on a statistical model of the habitat requirements of G. leadbeateri and which will better integrate wood production and the conservation of the species. This procedure accounts for the uncertainty in the statistical model and, in turn, reduces the risk that areas where G. leadbeateri occurs are logged, whilst ensuring that other areas are not unnecessarily excluded from timber harvesting.  相似文献   
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Remote national parks of the western U.S. and Alaska are not immune to contaminants of emerging concern. Semivolatile organic compounds (SOCs) such as pesticides and PCBs can selectively deposit from the atmosphere at higher rates in cold, high‐elevation and high‐latitude sites, potentially increasing risk to these ecosystems. In the environment, SOCs magnify up food chains and are known to increase health risks such as cancer and reproductive impairment. One hundred twenty‐eight fish in 8 national parks in Alaska and the western U.S. were analyzed for contaminant concentrations, assessed by region, and compared to human and wildlife health thresholds. SOC concentrations from an additional 133 fish from a previous study were also included, for a total of 31 water bodies sampled. PCBs, endosulfan sulfate, and p,p′‐DDE were among the most frequently detected contaminants. Concentrations of historic‐use pesticides dieldrin, p,p′‐DDE, and/or chlordanes in fish exceeded USEPA guidelines for human subsistence fish consumers and wildlife (kingfisher) health thresholds at 13 of 14 parks. Average concentrations in fish ranged from 0.6‐280 ng/g lipid (0.02‐7.3 μg/g ww). Contaminant loading was highest in fish from Alaskan and Sierra Nevada parks. Historic compounds were highest in Alaskan parks, while current‐use pesticides were higher in the Rockies and Sierra Nevada. This study provides a rigorous analysis of CECs in fish from national parks and identifies regions at potential risk.  相似文献   
57.
The term overfishing is being used with increasing frequency to designate an undesirable level of fisheries exploitation. All too often, however, the term is taken as being self-evident. This article demonstrates that many definitions of overfishing are possible, depending essentially on what objective is being pursued for the fishery. Various possible biological and economic objectives are considered, both in a static and dynamic model of the fishery. Consideration is given to the best utilization of the fish stock from the viewpoint of the individual fishermen as well as that of society. It is shown that overfishing by one definition may be underfishing by another, and it is concluded therefore that anyone using the term overfishing ought, as a matter of course, to define it.  相似文献   
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There is a widely acknowledged need for a single composite index that provides a comprehensive picture of the societal impact of disasters. A composite index combines and logically organizes important information policy‐makers need to allocate resources for the recovery from natural disasters; it can also inform hazard mitigation strategies. This paper develops a Disaster Impact Index (DII) to gauge the societal impact of disasters on the basis of the changes in individuals’ capabilities. The DII can be interpreted as the disaster impact per capita. Capabilities are dimensions of individual well‐being and refer to the genuine opportunities individuals have to achieve valuable states and activities (such as being adequately nourished or being mobile). After discussing the steps required to construct the DII, this article computes and compares the DIIs for two earthquakes of similar magnitude in two societies at different levels of development and of two disasters (earthquake and wind storm) in the same society.  相似文献   
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