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901.
Human biomonitoring (HBM), defined as the measurement of concentrations of chemicals or of their metabolites in human biological matrices, is considered the method of choice for determining internal exposures in individuals. HBM is part of environmental exposure surveillance systems in several countries. In 2007, the Ministry of Agriculture, Food and Environment promoted BIOAMBIENT.ES project, a national-level HBM study on environmental pollutants carried out in Spain to estimate levels of heavy metals, persistent organic pollutants, and other substances on the Spanish active workforce. BIOAMBIENT.ES is a nationwide cross-sectional study, with a stratified cluster sampling designed to cover all geographical areas, sex and occupational sectors, and aimed to obtain a representative sample of the Spanish workforce. Participants were recruited among people residing in Spain for 5 years or more, which underwent their annual occupational medical check-up in the health facilities of the Societies for Prevention of IBERMUTUAMUR, MUTUALIA, MC-PREVENCIÓN, MUGATRA, UNIMAT PREVENCIÓN, and PREVIMAC (March 2009–July 2010). A total of 1,892 subjects fulfilled the criteria for inclusion, donated biological samples (1,880 blood, 1,770 urine, and 577 hair) and completed a short self-administrated epidemiological questionnaire on environmental and lifestyle-related exposures. Additionally, clinical information from participant’s health exams was obtained. This project will provide a first overview of the body burden of selected pollutants in a representative sample of the Spanish-occupied population. This information will be useful to establish reference values of the studied population and, eventually, to evaluate temporal trends and the effectiveness of environmental and health policies.  相似文献   
902.
ABSTRACT

Research Triangle Institute and the U.S. Environmental Protection Agency conducted several projects to measure hydrocarbon emissions associated with the manufacture of fiberglass-reinforced plastics. The purpose of these projects was to evaluate pollution prevention techniques to reduce emissions by altering raw materials, application equipment, and operator technique. Analytical techniques were developed to reduce the cost of these emission measurements. Emissions from a small test mold in a temporary total enclosure (TTE) correlated with emissions from full-size production molds in a separate TTE. Gravimetric mass balance measurements inside the TTE generally agreed to within ± 30 % with total hydrocarbon (THC) measurements in the TTE exhaust duct. Pure styrene evaporation tests served as quality control checks for THC measurements and generally agreed to within ± 5 %.  相似文献   
903.
Development of stress markers for the invader freshwater zebra mussel (Dreissena polymorpha) is of great interest for both conservation and biomonitoring purposes. Gene expression profiles of several putative or already established gene expression stress markers (Metallothionein, Superoxide dismutase, Catalase, Glutathione S transferase, Glutathione peroxidase, Cytochrome c oxidase, the multixenobiotic resistance P-gp1, and heat shock proteins HSP70 and HSP90) were analyzed by quantitative Real-Time PCR in adults and pediveliger larvae after exposure to metals (Hg, Cu, Cd). A defined pattern of coordinated responses to metal exposure and, presumably, to oxidative stress was observed in gills and digestive gland from adults. A similar, albeit partial response was observed in larvae, indicating an early development of stress-related gene responses in zebra mussel. The tools developed in this study may be useful both for future control strategies and for the use of zebra mussel as sentinel species in water courses with stable populations.  相似文献   
904.
Progress towards climate change aware regional sustainable development is affected by actions at multiple spatial scales and governance levels and equally impacts actions at these scales. Many authors and policy practitioners consider therefore that decisions over policy, mitigation strategies and capacity for adaptation to climate change require construction and coordination over multiple levels of governance to arrive at acceptable local, regional and global management strategies. However, how such processes of coordination and decision-aiding can occur and be maintained and improved over time is a major challenge in need of investigation. We take on this challenge by proposing research-supported methods of aiding multi-level decision-making processes in this context. Four example regionally focussed multi-level case studies from diverse socio-political contexts are outlined—estuarine management in Australia’s Lower Hawkesbury, flood and drought management in Bulgaria’s Upper Iskar Basin, climate policy integration in Spain’s Comunidad Valenciana and food security in Bangladesh’s Faridpur District—from which insights are drawn. Our discussion focuses on exploring these insights including: (1) the possible advantages of informal research-supported processes and specifically those that provide individual arenas of participation for different levels of stakeholders; (2) the complexity of organisation processes required for aiding multi-level decision-making processes; and (3) to what extent progress towards integrated regional policies for climate change aware sustainable development can be achieved through research-supported processes. We finish with a speculative section that provides ideas and directions for future research.  相似文献   
905.
Environmental Economics and Policy Studies - The literature is abundant with studies analyzing inequality in carbon emissions at the macroeconomic level, but very limited at the household level....  相似文献   
906.
A major task related to conservation is to predict if planned infrastructure projects are likely to threaten biodiversity. In this study we investigated the potential impact of planned infrastructure in Spain on amphibian and reptile species, two highly vulnerable groups given their limited dispersal and current situation of population decline. We used distribution data of both groups to identify areas of high herpetofauna diversity, and compared the locations of these areas with the locations of the planned road, high-speed train railway and water reservoir network. Four criteria were used for this identification: species richness, rarity, vulnerability, and a combined index of the three criteria. From a total of 1441 cells of 20 x 20 km, areas of high diversity were defined as those cells whose ranked values for the different criteria included either all species or all threatened species. The combined index provided the smallest number of cells needed to retain all threatened species (1.7 and 2.6% of the cells for amphibian and reptile species, respectively). Coincidences between these high diversity areas and cells including planned infrastructures-denominated 'alert planning units'-were 35.4% for amphibians and 31.2% for reptiles. Mitigation of the potential impacts would include actions such as barriers to animal access to roads and railways and ecoducts under these constructions. Our approach provides conservation authorities information that can be used to make decisions on habitat protection. A technique that identifies threats to herpetofauna before they occur is also likely to improve the chance of herpetofauna being protected.  相似文献   
907.
Resource exploitation in lowland tropical forests is increasingand causing loss of biodiversity. Effective evaluation and management of the impacts of development on tropical forests requires appropriate assessment and monitoring tools. We proposethe use of 0.1-ha multi-scale, modified Whittaker plots (MWPs) to assess and monitor vegetation in lowland tropical rainforests.We established MWPs at 4 sites to: (1) describe and comparecomposition and structure of the sites using MWPs, (2) compare these results to those of 1-ha permanent vegetation plots (BDPs),and (3) evaluate the ability of MWPs to detect changes in populations (statistical power). We recorded more than 400 species at each site. Species composition among the sites was distinctive, while mean abundance and basal area was similar. Comparisons between MWPs and BDPs show that they record similarspecies composition and abundance and that both perform equallywell at detecting rare species. However, MWPs tend to record morespecies, and power analysis studies show that MWPs were more effective at detecting changes in the mean number of species of trees 10 cm in diameter at breast height (dbh) and in herbaceous plants. Ten MWPs were sufficient to detect a change of 11% in the mean number of herb species, and they were able to detect a 14% change in the mean number of species of trees 10 cm dbh. The value of MWPs for assessment and monitoringis discussed, along with recommendations for improving the sampling design to increase power.  相似文献   
908.
909.
The assessment of management effectiveness in protected areas, i.e., the evaluation of whether management strategies are actually helping to achieve stated goals, is becoming a priority. In any such evaluation, accurate information concerning the dynamics of the managed system is required—information that is gathered through monitoring. Few protected areas, however, have well-developed monitoring plans, and reserve managers are faced with a shortage of protocols for their design. This paper proposes a methodology, applicable to a wide range of situations, for designing such plans. The process begins with the precise definition of the aims of the monitoring plan, followed by the identification of key ecological processes and management objectives for the area, and finally the selection of a reduced set of indicators. These indicators are represented at three levels of growing complexity, allowing the plan to be followed in a modular fashion and in agreement with available resources.  相似文献   
910.
We investigate the phylogeography of California (Zalophus californianus) and Galápagos (Z. wollebaeki) sea lions and describe within-population structure for the California sea lion based on mitochondrial DNA. Fifty control-region haplotypes were found, 41 from Z. californianus and 9 from Z. wollebaeki, with three fixed differences between the two species. Ranked population boundaries along the range of Z. californianus were defined based on the Monmonier Maximum Difference Algorithm, resulting in five genetically distinct populations, two in the Pacific Ocean and three inside the Gulf of California. A Minimum Spanning Network showed a strong phylogeographic signal with two well-defined clusters, Z. californianus and Z. wollebaeki, separated by six base-pair differences, supporting the existence of two genetically distinct species with an estimated divergence time of ~0.8 Ma. Results are discussed in the context of the historical geologic and paleoceanographic events of the last 1 Ma in the eastern Pacific.  相似文献   
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