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61.
    
The paradoxical tensions in corporate sustainability is hotly debated in the literature. Some authors have underlined the need for empirical works in this field, and the circular economy could help to bridge this gap. The circular economy creates contrasting challenges for companies, which lead to paradoxical tensions. On the one hand, companies pursue circular economy goals—such as the use of recycled raw materials—thus highlighting their environmental commitment. On the other hand, such usage may affect the quality and consequently the competitiveness of products. Our study investigates the acknowledgement of these tensions and the strategies adopted by companies to manage them. Using a multiple case study approach, we focus on an Italian sample of three manufacturing sectors: paper production, textile/clothing, and leather. The results show the different defensive and proactive strategies adopted by firms highlighting, in one case, a relevant opportunity exploited by a company considered in the sample. Our paper contributes to the existing knowledge on paradoxical tensions management in companies involved in corporate sustainability inviting scholars towards new research avenues focused on circular economy.  相似文献   
62.
Land Evaluation for Maize Based on Fuzzy Set and Interpolation   总被引:1,自引:0,他引:1  
The objective of this article is to apply fuzzy set and interpolation techniques for land suitability evaluation for maize in Northern Ghana. Land suitability indices were computed at point observations using the Semantic Import (SI) model, whereas spatial interpolation was carried out by block kriging. Interpolated land suitability shows a high correlation (R2 = 0.87) with observed maize yield at the village level. This indicates that land suitability is closely related to maize yield in the study area. Membership functions were further used to assess the degree of limitation of land characteristics to maize. Sixty percent of the data has membership functions ranging from 0.23 for ECEC to 1.00 for drainage. ECEC, organic C, and clay are the major constraints to maize yield. The use of the fuzzy technique is helpful for land suitability evaluation, especially in applications in which subtle differences in soil quality are of a major interest. Furthermore, the use of kriging that exploits spatial variability of data is useful in producing continuous land suitability maps and in estimating uncertainties associated with predicted land suitability indices.  相似文献   
63.
Currently, there is a need for a better multidisciplinary education system for tropical conservation, as well as a need for more people from developing countries to receive such improved education and training. If this combination is achieved, universities in both developed and developing nations will likely produce graduates who are better prepared for jobs involving non-academic tropical conservation initiatives and, simultaneously produce graduates who may be better accepted as conservationists in tropical destinations.  相似文献   
64.
To detect effects of Cu pollution, the Cu tolerance of soil bacterial communities extracted from several vineyards located in NW Spain was measured. Bacterial community tolerance was estimated by means of the thymidine (TdR) and leucine (Leu) incorporation techniques using either IC(50) values (the log of the metal concentration that reduced incorporation to 50%) or the percentage of activity at one specific Cu concentration (10(-6) mol L(-1)). The tolerance measurements by the TdR incorporation technique were similar to those obtained by the Leu incorporation method, indicating that the two methods were equivalent in terms of suitability for detecting the toxicity of Cu to soil bacterial communities. The two tolerance indices considered (IC50 values and percentage of activity) were closely correlated (r = 0.975, P < 0.001), showing that both were equally good in measuring Cu tolerance of the bacterial community. An increased bacterial community tolerance to Cu, indicating a pollution effect, was observed in vineyard soils with more than 100 mg Cu kg(-1) soil. Thus, the long-term use of Cu in vineyards has a toxic effect on the soil bacterial community, resulting in an increased tolerance. An effect of increased levels of Cu could not be detected when measuring bacterial community activity, pointing to the increased sensitivity to detect toxicity in field studies using tolerance measurements.  相似文献   
65.
River restoration is becoming a priority in many countries because of increasing the awareness of environmental degradation. In Europe, the EU Water Framework Directive (WFD) has significantly reinforced river restoration, encouraging the improvement of ecological status for water bodies. To fulfill the WFD requirements, the Spanish Ministry of the Environment developed in 2006 a National Strategy for River Restoration whose design and implementation are described in this paper. At the same time many restoration projects have been conducted, and sixty of them have been evaluated in terms of stated objectives and pressures and implemented restoration measures. Riparian vegetation enhancement, weir removal and fish passes were the most frequently implemented restoration measures, although the greatest pressures came from hydrologic alteration caused by flow regulation for irrigation purposes. Water deficits in quantity and quality associated with uncontrolled water demands seriously affect Mediterranean rivers and represent the main constraint to achieving good ecological status of Spanish rivers, most of them intensively regulated. Proper environmental allocation of in-stream flows would need deep restrictions in agricultural water use which seem to be of very difficult social acceptance. This situation highlights the need to integrate land-use and rural development policies with water resources and river management, and identifies additional difficulties in achieving the WFD objectives and good ecological status of rivers in Mediterranean countries.  相似文献   
66.
    
Systematic conservation planning and Key Biodiversity Areas (KBAs) are the two most widely used approaches for identifying important sites for biodiversity. However, there is limited advice for conservation policy makers and practitioners on when and how they should be combined. Here we provide such guidance, using insights from the recently developed Global Standard for the Identification of KBAs and the language of decision science to review and clarify their similarities and differences. We argue the two approaches are broadly similar, with both setting transparent environmental objectives and specifying actions. There is however greater contrast in the data used and actions involved, as the KBA approach uses biodiversity data alone and identifies sites for monitoring and vigilance actions at a minimum, whereas systematic conservation planning combines biodiversity and implementation-relevant data to guide management actions. This difference means there is much scope for combining approaches, so conservation planners should use KBA data in their analyses, setting context-specific targets for each KBA type, and planners and donors should use systematic conservation planning techniques when prioritizing between KBAs for management action. In doing so, they will benefit conservation policy, practice and research by building on the collaborations formed through the KBA Standard's development.  相似文献   
67.
    
Plastics offer several benefits, such as durability, versatility, and cost-effectiveness, which have led to their pervasive use in nearly every aspect of modern life. However, their widespread use has led to significant environmental concerns. One of the major issues is their persistence in the environment, where they accumulate and cause contamination. This problem is particularly severe with plastic packaging and microparticles used in cosmetic products. As a result, the cosmetics industry started producing environmentally sustainable glitter. “Biodegradable” glitter is available in distinct compositions, mainly with a central base composed of a biodegradable material. This review focuses on academic research and patents related to glitter and biodegradable glitter, aiming to classify and compare commercially available options. Furthermore, this review analyzes scientific research on conventional glitter and its conclusions regarding environmental impact. For this, we used the keywords “glitter,” “biodegradable glitter,” “eco-friendly glitter,” “natural glitter,” and “sustainable glitter” in the databases of Wiley, Science Direct, Springer, and Clarivate Analytics ISI—Web of Science. We also performed a bibliometric analysis using the keyword “glitter” in the Web of Science database to obtain a bibliometric map of publication trends in the field using VOSviewer software. The products identified in the search were analyzed for their components and biodegradation potential. These products were classified as “biodegradable” if they were composed entirely of biodegradable constituents and as “eco-friendly” if only a portion of their constituents was biodegradable. We observed that several glitter products are incorrectly classified as biodegradable, demonstrating the need for standardized terminology that accurately reflects the composition of the glitter particles. Patent applications indicate a growing interest in developing environmentally safe glitter particles in recent years. Studies on conventional glitter mainly focus on its environmental impact or discuss analyzes for the identification and classification of glitter particles. The data gathered highlight the gaps in the field, mainly related to glitter production methods and the standardization of biodegradable glitter. Thus, studies in this direction are highly necessary.  相似文献   
68.
    
Three hundred and three biogas plants, representing a majority of the units installed in Sri Lanka up to 1984, were inspected, and it was found that 280 of these had been put into commission at some time prior to the study. Of the 280 commissioned plants, 170 (61%) were functioning satisfactorily providing biogas for cooking and/or lighting. The remaining 110 (39%) were either not functioning or were supplying very little gas owing to gas leaks, inadequate input of dung, or poor plant management. The most common plant was the 6 m3, fixed dome, household plant, and the most common raw material used was cattle dung. In the majority of household plants the cost of construction was partly or wholly subsidized.  相似文献   
69.
Studies on selective demolition (also named deconstruction) in the past few years have produced some high quality economic, material and environmental information. Economic data, however, varies considerably between regions since local conditions strongly influence labour costs, tipping fees and/or market prices for recovered materials. Regional financial and regulatory constraints will bind the economic viability of conventional and selective demolition choices, which are essentially economic in a free market. Given this, the present study evaluates the economic implications of the two demolition types by analyzing a case study in Portugal. A few scenarios are considered, based on possible waste management options, some of which favour selective demolition over the conventional type.  相似文献   
70.
The article focuses on fossil energy resources in the Andean Group and Mexico, and argues for a dynamic approach to calculating reserves to production ratios. Individual countries are surveyed in terms of estimated reserves of fossil energy resources, current production rates and future prospects; energy policy options for individual countries are analysed. As a primary objective of energy policy is to ensure security of supply, it is important that calculations of reserves to production ratios accurately estimate the desired level of investment in exploration. The calculations need to take into account a variety of parameters, including different energy sources, availability and risk; geographic considerations including proximity, transport, storage capacity and commercial aspects; the competitive and environmental implications of developing indigenous resources; and the use of instruments to establish contingency plans for emergencies.
The opinions expressed in this article are those of the authors, and do not necessarily reflect the views of OLADE, ECLAC or GTZ. The authors apologize for any inaccuracies or omissions in the article.  相似文献   
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