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221.
This article discusses the development of corporate social responsibility (CSR) in Brazil from the perspective of the Ethos Institute of Business and Social Responsibility. The Institute is a not‐for‐profit, non‐governmental organization, that has played a leading role in the Brazilian CSR effort. In Brazil, CSR initiatives have a long tradition of philanthropy, a consequence of the country's great social inequalities. The increased attention to corporate social responsibility has paralleled growing concern about sustainable development and the intensifying activities of pressure groups (consumers, customers, investors, NGOs, labour unions, the media, among others) that have been increasing since the 1990s as natural resources are progressively becoming exhausted, social tensions rising and environmental conditions deteriorating worldwide. This article identifies problems and obstacles to the growth of corporate social responsibility in Brazil, as well as advances and alternatives for CSR and towards creating conditions for the country to be internationally competitive and sustainable in the financial, social and environmental areas.  相似文献   
222.
考虑到当前主要的环境和社会问题,很明显我们人类所面临的最大挑战就是使人类文明具有可持续性 .这不仅仅是实现持续发展的问题,而是要实现一种具有可持续性的社会模式 .这就给产业提出了环境、社会、经济和政治方面的挑战,要求产业必须降低资源消耗、更公平地分配商品和服务、减少南北方国家之间的生态债 .同时还必须共享经济和政治权力,用"星球化"代替全球化 .  相似文献   
223.
Fire, elephants, and frost are important disturbance factors in many African savannas, but the relative magnitude of their effects on vegetation and their interactions have not been quantified. Understanding how disturbance shapes savanna structure and composition is critical for predicting changes in tree cover and for formulating management and conservation policy. A simulation model was used to investigate how the disturbance regime determines vegetation structure and composition in a mixed Kalahari sand woodland savanna in western Zimbabwe. The model consisted of submodels for tree growth, tree damage caused by disturbance, mortality, and recruitment that were parameterized from field data collected over a two-year period. The model predicts that, under the current disturbance regime, tree basal area in the study area will decline by two-thirds over the next two decades and become dominated by species unpalatable to elephants. Changes in the disturbance regime are predicted to greatly modify vegetation structure and community composition. Elephants are the primary drivers of woodland change in this community at present-day population densities, and their impacts are exacerbated by the effects of fire and frost. Frost, in particular, does not play an important role when acting independently but appears to be a key secondary factor in the presence of elephants and/or fire. Unlike fire and frost, which cannot suppress the woodland phase on their own in this ecosystem, elephants can independently drive the vegetation to the scrub phase. The results suggest that elephant and fire management may be critical for the persistence of certain woodland communities within dry-season elephant habitats in the eastern Kalahari, particularly those dominated by Brachystegia spiciformis and other palatable species.  相似文献   
224.
225.
Costa Rica is a nation with a vast wealth of water resources; however, recently the country has faced water conflicts (WC) due to social, economic, legal, and political impediments in response to limited water availability during El Niño events and inefficient use of its water resources. This study presents a spatial distribution and temporal analysis of WC in Costa Rica from 2005 to 2015. In total, 719 WC were analyzed of which 54% were among private individuals and government. The largest urban areas and the Grande de Tárcoles Basin were identified as the main “hot spot” for the conflicts. WC were mainly caused by spills of wastewater, water pollution, water shortage, infrastructure damage, and flooding, and can be predicted using a multiple linear model including the population size and the number of hydro‐meteorological events (HME) (R2 = 0.77). The identified HME also coevolved significantly with the changes in precipitation regimes (r = 0.67, = 0.021). Our results suggest that there is a need to recognize that water infrastructure longevity across the country concatenates and amplifies WC, mainly in the most populated area located in the Central Valley. Implications of our findings include the need for truly integrated water resources management plans that include, for example, WC as indicators of hydro‐climatic changing conditions and water supply and sanitation infrastructure status.  相似文献   
226.
The recent growth of online big data offers opportunities for rapid and inexpensive measurement of public interest. Conservation culturomics is an emerging research area that uses online data to study human–nature relationships for conservation. Methods for conservation culturomics, though promising, are still being developed and refined. We considered the potential of Wikipedia, the online encyclopedia, as a resource for conservation culturomics and outlined methods for using Wikipedia data in conservation. Wikipedia's large size, widespread use, underlying data structure, and open access to both its content and usage analytics make it well suited to conservation culturomics research. Limitations of Wikipedia data include the lack of location information associated with some metadata and limited information on the motivations of many users. Seven methodological steps to consider when using Wikipedia data in conservation include metadata selection, temporality, taxonomy, language representation, Wikipedia geography, physical and biological geography, and comparative metrics. Each of these methodological decisions can affect measures of online interest. As a case study, we explored these themes by analyzing 757 million Wikipedia page views associated with the Wikipedia pages for 10,099 species of birds across 251 Wikipedia language editions. We found that Wikipedia data have the potential to generate insight for conservation and are particularly useful for quantifying patterns of public interest at large scales.  相似文献   
227.
In this study we performed a survey of the bacterial communities associated with the Western Atlantic demosponges Hymeniacidon heliophila and Polymastia janeirensis, based on 16S rRNA sequencing and transmission electron microscopy (TEM). We compared diversity and composition of the sponge-associated bacteria to those of environmental bacteria, represented by free-living bacterioplankton and by bacteria attached to organic particulate matter in superficial sediments. Partial bacterial 16S rRNA sequences from seawater, sediment, and sponges were retrieved by PCR, cloning, and sequencing. Sequences were subjected to rarefaction analyses, phylogenetic tree construction, and LIBSHUFF quantitative statistics to verify coverage and similarity between libraries. Community structure of the free-living bacterioplankton was phylogenetically different from that of the sponge-associated bacterial assemblages. On the other hand, some sediment-attached bacteria were also found in the sponge bacterial community, indicating that sponges may incorporate bacteria together with sediment particles. Rare and few prokaryotic morphotypes were found in TEM analyses of sponge mesohyl matrix of both species. Molecular data indicate that bacterial richness and diversity decreases from bacterioplankton, to particulate organic sediment, and to H. heliophila and P. janeirensis. Sponges from Rio de Janeiro harbor a pool of novel and exclusive sponge-associated bacterial taxa. Sponge-associated bacterial communities are composed of both taxons shared by many sponge groups and by species-specific bacteria.  相似文献   
228.
Environmental Science and Pollution Research - Here, we show the electrical response, bacterial community, and remediation of hydrocarbon-contaminated groundwater from a gasworks site using a...  相似文献   
229.
The objective of this study was to evaluate the effect of frequent and periodic applications of sewage sludge to the soil, on corn productivity. The experiment was carried out as part of an experiment that has been underway since 1999, using two types of sludge. One came from the Barueri Sewage Treatment Station (BS, which receives both household and industrial sludge) and the other came from the Franca Sewage Treatment Station (FS, which receives only household sludge). The Barueri sludge was applied from 1999 up to the agricultural year of 2003/2004. With the exception of the agricultural years of 2004/2005 and 2005/2006, the Franca sludge was applied up to 2008/2009. All the applications were made in November, with the exception of the first one which was made in April 1999. After harvesting the corn, the soil remained fallow until the next cultivation. The experiment was set up as a completely randomized block design with three replications and the following treatments: control without chemical fertilization or sludge application, mineral fertilization, and dose 1 and dose 2 of sludge (Franca and Barueri). The sludges were applied individually. Dose 1 was calculated by considering the recommended N application for corn. Dose 2 was twice dose 1. It was evident from this work that the successive application of sludge to the soil in doses sufficient to reach the productivity desired with the use of nitrogen fertilizers could cause environmental problems due to N losses to the environment and that the residual and cumulative effects should be considered when calculating the application of sludge to soil.  相似文献   
230.
Some relevant shortcomings have been identified in the current approach for the classification of ecological status in marine water bodies, leading to delays in the fulfillment of the Water Framework Directive objectives. Natural variability makes difficult to settle fixed reference values and boundary values for the Ecological Quality Ratios (EQR) for the biological quality elements. Biological responses to environmental degradation are frequently of nonmonotonic nature, hampering the EQR approach. Community structure traits respond only once ecological damage has already been done and do not provide early warning signals. An alternative methodology for the classification of ecological status integrating chemical measurements, ecotoxicological bioassays and community structure traits (species richness and diversity), and using multivariate analyses (multidimensional scaling and cluster analysis), is proposed. This approach does not depend on the arbitrary definition of fixed reference values and EQR boundary values, and it is suitable to integrate nonlinear, sensitive signals of ecological degradation. As a disadvantage, this approach demands the inclusion of sampling sites representing the full range of ecological status in each monitoring campaign. National or international agencies in charge of coastal pollution monitoring have comprehensive data sets available to overcome this limitation.  相似文献   
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