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51.
Hookworms in otariids are considered to meet the conditions and to fulfill the predictions set forth in the theoretical literature to define a likely case of host coexistence mediation by a shared pathogen. The intensity of infections, the prevalence of skin lesions and the morphometry of hookworms Uncinaria spp. were examined in South American sea lions and fur seals sampled along the Chilean and the Uruguayan coasts in spring and summer 1981 to 1991. In sympatric host populations from Uruguay, there were clear differences in intensity of infections, prevalence of skin lesions, and body size of the hookworms from the two host species. Sea lions from Chile, allopatric to fur seal populations, are less intensively infected and hookworms found in these sea lions have the smallest body size reported in otariids, while those from South American fur seals are the largest. Hookworms found in sea lion pups from populations sympatric to fur seals revealed intermediate values in intensity and in body size, and the sea lion pups had the highest prevalence of skin lesions. Other reports of hookworms in otariids show intermediate morphometry, following a general linear trend of differentiation in size. Consequently, they are considered to belong to the same, widely distributed species Uncinaria lucasi Stiles, 1901.  相似文献   
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Environmental Science and Pollution Research - The port regions of the Amazon are subject to environmental impacts high shipping traffic. In October 2015, a cargo ship containing 5000 oxen sank in...  相似文献   
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Although there has been a worldwide growing concern regarding solid-waste management, the rural area has been left behind on this matter. It is common knowledge that the lack of waste management is very detrimental to the environment and impact seriously the public health. Therefore, the aim of this work is to contribute to the decision-making process regarding waste management in the rural area by proposing a new methodology using the combination of risk analysis and complementary sustainability criteria. The proposed methodology was demonstrated through a case study in the State of Mato Grosso do Sul, Brazil. A field survey was performed to define the current scenarios and three new scenarios were proposed. The risk analysis showed that the major risk to which residents are vulnerable to is the appearance of vectors that can cause various types of diseases. Besides that, only 30% of rural Quilombola communities of Mato Grosso do Sul have waste collection and the predominant scenario is the burning of dry waste and use of organic waste for animal feeding. Using the complementary relevant criteria, the most suitable scenario do the studied communities would be the combination of household composting and source separation of dry waste. The proposed methodology can be easily applied to other rural regions seeking for sustainable waste management systems.  相似文献   
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The Convention on Biological Diversity proposed the Aichi Biodiversity Targets to improve conservation policies and to balance economic development, social welfare, and the maintenance of biodiversity/ecosystem services. Brazil is a signatory of the Aichi Biodiversity Targets and is the most diverse country in terms of freshwater fish, but its national policies have supported the development of unsustainable commercial and ornamental aquaculture, which has led to serious disturbances to inland ecosystems and natural resources. We analyzed the development of Brazilian aquaculture to show how current aquaculture expansion conflicts with all 20 Aichi Targets. This case suggests that Brazil and many other megadiverse developing countries will not meet international conservation targets, stressing the need for new strategies, such as the environmental management system, to improve biodiversity conservation.  相似文献   
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Environmental Science and Pollution Research - Natural pozzolan is an amorphous silicate-based material of volcanic origin. In this work, the natural pozzolan was modified by using...  相似文献   
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This study evaluates the spatial patterns of land occupation and their relationship to water quality in the Cuiabá River watershed, one of the main affluents of the Pantanal floodplain. The impact of farming and other land occupation forms were studied using a three year time series. Monitoring included 15 parameters at 21 stations with a total of 1266 different samples. Ten stations along the Cuiabá River were ordinated by Principal Component Analysis (PCA). For an exploratory analysis in the spatial domain, sub-basins of the Cuiabá watershed were classified according to mean concentrations of selected water quality parameters. Supervised classification of digital Landsat ETM imagery and standard GIS techniques were applied to parameterize land use and occupation according to a watershed scale. Redundancy Analysis (RDA) was then used to evaluate impacts of environmental and socio-economic factors on water quality.A Cuiabá headwater station only shows slightly elevated total coliform counts and concentrations of nutrients in the river after it passes regions of extensive cattle farming. After the confluence with the Manso River, nutrient and COD concentrations increase significantly, receiving loads from sub-basins under intensive agricultural land use, with mean annual concentrations up to 1.74 mg/L of total nitrogen (Kjedahl). Sub-watersheds with intensive fishing culture activities were shown to have significant impact on nitrogen concentrations, reaching mean concentrations of 2.66 mg/L of total nitrogen in the affluents. Most serious biological and chemical water pollution can be observed at stream outlets in the urban agglomeration of Cuiabá/Várzea Grande. Affluent pollution is reflected in the water quality of the Cuiabá River: subsequent monitoring stations in the urban area are ordinated on a gradient of increasing degradation of chemical and biological water quality. The auto-depuration capacity of the Cuiabá River is intact, but elevated concentrations of Phosphorous and Chemical Oxygen Demand can be observed as far away as the Pantanal floodplain, about 120 km downstream from the urban agglomeration.  相似文献   
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The personal assessments of the current and expected future state of the environment by 3232 community respondents in 18 nations were investigated at the local, national, and global spatial levels. These assessments were compared to a ranking of each country's environmental quality by an expert panel. Temporal pessimism (“things will get worse”) was found in the assessments at all three spatial levels. Spatial optimism bias (“things are better here than there”) was found in the assessments of current environmental conditions in 15 of 18 countries, but not in the assessments of the future. All countries except one exhibited temporal pessimism, but significant differences between them were common. Evaluations of current environmental conditions also differed by country. Citizens' assessments of current conditions, and the degree of comparative optimism, were strongly correlated with the expert panel's assessments of national environmental quality. Aside from the value of understanding global trends in environmental assessments, the results have important implications for environmental policy and risk management strategies.  相似文献   
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