全文获取类型
收费全文 | 3472篇 |
免费 | 38篇 |
国内免费 | 43篇 |
专业分类
安全科学 | 89篇 |
废物处理 | 161篇 |
环保管理 | 441篇 |
综合类 | 503篇 |
基础理论 | 1241篇 |
污染及防治 | 697篇 |
评价与监测 | 209篇 |
社会与环境 | 204篇 |
灾害及防治 | 8篇 |
出版年
2023年 | 11篇 |
2022年 | 9篇 |
2021年 | 26篇 |
2020年 | 18篇 |
2019年 | 21篇 |
2018年 | 138篇 |
2017年 | 144篇 |
2016年 | 228篇 |
2015年 | 79篇 |
2014年 | 40篇 |
2013年 | 72篇 |
2012年 | 456篇 |
2011年 | 251篇 |
2010年 | 50篇 |
2009年 | 55篇 |
2008年 | 91篇 |
2007年 | 82篇 |
2006年 | 94篇 |
2005年 | 411篇 |
2004年 | 543篇 |
2003年 | 423篇 |
2002年 | 69篇 |
2001年 | 57篇 |
2000年 | 25篇 |
1999年 | 32篇 |
1998年 | 6篇 |
1997年 | 11篇 |
1996年 | 4篇 |
1995年 | 12篇 |
1994年 | 5篇 |
1993年 | 5篇 |
1992年 | 9篇 |
1991年 | 10篇 |
1990年 | 9篇 |
1989年 | 6篇 |
1988年 | 2篇 |
1987年 | 6篇 |
1986年 | 5篇 |
1984年 | 3篇 |
1982年 | 5篇 |
1981年 | 3篇 |
1980年 | 3篇 |
1979年 | 4篇 |
1975年 | 2篇 |
1974年 | 3篇 |
1972年 | 2篇 |
1967年 | 1篇 |
1966年 | 2篇 |
1961年 | 1篇 |
1957年 | 1篇 |
排序方式: 共有3553条查询结果,搜索用时 15 毫秒
921.
922.
923.
Even when environmental data quantify the risks and benefits of delayed responses to rapid anthropogenic change, institutions rarely respond promptly. We propose that narratives complementing environmental datasets can motivate responsive environmental policy. To explore this idea, we relate a case study in which a narrative of economic loss due to regionally rapid ocean acidification—an anthropogenic change—helped connect knowledge with action. We pose three hypotheses to explain why narratives might be particularly effective in linking science to environmental policy, drawing from the literature of economics, environmental policy, and cognitive psychology. It seems that yet-untold narratives may hold similar potential for strengthening the feedback between environmental data and policy and motivating regional responses to other environmental problems. 相似文献
924.
Indra?Elena?C.?EscobarEmail author Vilma?M.?Santos Danielle?Karla?A.?da?Silva Marcelo?F.?Fernandes Uided?Maaze?T.?Cavalcante Leonor?C.?Maia 《Environmental management》2015,55(6):1433-1445
The aim of this study was to describe the impact of re-vegetation on the restoration of microbial community structure and soil microbiological properties in sand dunes that had been affected by mining activity. Soil samples were collected during the dry and rainy seasons from a chronosequence (1, 9, 21 years) of re-vegetated dunes using a single preserved dune as a reference. The composition of the fatty acid methyl esters and soil microbial properties were evaluated. The results showed that the changes in microbial community structure were related to seasonal variations: biomarkers of Gram-positive bacteria were higher than Gram-negative bacteria during the dry season, showing that this group of organisms is more tolerant to these stressful conditions. The microbial community structure in the natural dune was less affected by seasonal variation compared to the re-vegetated areas, whereas the opposite was observed for microbiological properties. Thus, in general, the proportion of saprobic fungi was higher in the natural dune, whereas Gram-negative bacteria were proportionally more common in the younger areas. Although over time the re-vegetation allows the recovery of the microbial community and the soil functions, these communities and functions are different from those found in the undisturbed areas. 相似文献
925.
Corey D. Wallace Ryan T. Bailey 《Journal of the American Water Resources Association》2015,51(1):185-199
Atoll island communities rely on rainwater catchment systems (RWCS) as a primary method of storing freshwater. However, stored freshwater can be depleted during times of drought, requiring importation of water to sustain community living. To maintain adequate water supply under future climatic conditions, the functioning of RWCS for atoll communities must be analyzed and optimal designs must be adopted. In this study, a quantitative analysis of stored daily water volumes is provided for atoll islands within the Federated States of Micronesia (FSM), with Nikahlap Island, Pakein Atoll, and a generic island in western FSM used as representative cases. Using a daily water balance model for the RWCS, baseline conditions are simulated for the 1997‐1999 time period, during which an intense El Niño‐induced drought occurred, and a sensitivity analysis is performed to quantify the influence of RWCS features on water system outputs, whereupon an optimal RWCS design using existing infrastructure is analyzed. Results indicate the strong influence of catchment area, system efficiency, and storage capacity on water volumes and the depletion of water during dry seasons and drought periods using current RWCS infrastructure. Adequate storage can be maintained during a major drought if unused RWCS features are employed and if minimal rationing is adopted. Study results provide water resource managers and government officials with valuable data for consideration in water security measures. 相似文献
926.
927.
Gary?Mahoney Alex?G.?StewartEmail author Nattalie?Kennedy Becky?Whitely Linda?Turner Ewan?Wilkinson 《Environmental geochemistry and health》2015,37(4):689-706
While scientific understanding of environmental issues develops through careful observation, experiment and modelling, the application of such advances in the day to day world is much less clean and tidy. Merseyside in northwest England has an industrial heritage from the earliest days of the industrial revolution. Indeed, the chemical industry was borne here. Land contamination issues are rife, as are problems with air quality. Through the examination of one case study for each topic, the practicalities of applied science are explored. An integrated, multidisciplinary response to pollution needs more than a scientific risk assessment. The needs of the various groups (from public to government) involved in the situations must be considered, as well as wider, relevant contexts (from history to European legislation), before a truly integrated response can be generated. However, no such situation exists in isolation and the introduction of environmental investigations and the exploration of suitable, integrated responses will alter the situation in unexpected ways, which must be considered carefully and incorporated in a rolling fashion to enable solutions to continue to be applicable and relevant to the problem being faced. This integrated approach has been tested over many years in Merseyside and found to be a robust approach to ever-changing problems that are well described by the management term, “wicked problems”. 相似文献
928.
Nest- and colony-mate recognition in polydomous colonies of meat ants (Iridomyrmex purpureus) 总被引:3,自引:1,他引:2
Workers of polydomous colonies of social insects must recognize not only colony-mates residing in the same nest but also those living in other nests. We investigated the impact of a decentralized colony structure on colony- and nestmate recognition in the polydomous Australian meat ant (Iridomyrmex purpureus). Field experiments showed that ants of colonies with many nests were less aggressive toward alien conspecifics than those of colonies with few nests. In addition, while meat ants were almost never aggressive toward nestmates, they were frequently aggressive when confronted with an individual from a different nest within the same colony. Our chemical analysis of the cuticular hydrocarbons of workers using a novel comprehensive two-dimensional gas chromatography technique that increases the number of quantifiable compounds revealed both colony- and nest-specific patterns. Combined, these data indicate an incomplete transfer of colony odor between the nests of polydomous meat ant colonies. 相似文献
929.
We investigated the roles of resource availability and phenotypic plasticity in promoting ecological character displacement (i.e., trait evolution stemming from resource competition between species). Because ecological character displacement generates new populations that differ in resource use, this process should only occur when exploitable resources are available. We tested this hypothesis in two species of spadefoot toads (Spea bombifrons and S. multiplicata) whose tadpoles use phenotypic plasticity to develop into either an omnivore morph, which specializes on detritus, or a physically distinctive carnivore morph, which specializes on shrimp. Both species grow best on shrimp, but when reared together, S. bombifrons outcompetes S. multiplicata for shrimp and S. multiplicata outcompetes S. bombifrons for detritus. We found that when each species occurred alone in the field, they produced similar proportions of omnivores and carnivores. When the two species occurred together, however, they underwent ecological character displacement in larval development, with S. multiplicata producing mostly omnivores, and S. bombifrons producing mostly carnivores. We combined observations of natural populations with experiments to evaluate whether such character displacement was only possible when both shrimp and detritus were relatively abundant. Mixed-species ponds contained abundant detritus and shrimp, in contrast with nearby pure-species ponds, which were deficient in one resource. Experiments revealed that S. multiplicata competed poorly when detritus was rare and that S. bombifrons competed poorly when shrimp was rare. In nature, when one of these two resources was scarce, one species was missing, perhaps through competitive exclusion by the species that was the superior competitor for the remaining resource. Thus, ecological character displacement and, therefore, coexistence of close competitors, was only possible when diverse resources were available. Finally, even if exploitable resources are available, character displacement is not guaranteed to transpire if species cannot utilize such resources expeditiously. Phenotypic plasticity provides a general and important mechanism for facilitating resource partitioning. Thus, by facilitating shifts in resource use, phenotypic plasticity and ecological opportunity may often interact to promote divergence and coexistence of competitors. 相似文献
930.
Cresser MS Ahmed N Smart RP Arowolo T Calver LJ Chapman PJ 《Environmental pollution (Barking, Essex : 1987)》2006,143(2):361-366
Monthly stream water calcium and Gran alkalinity concentration data from 11 sub-catchments of the Nether Beck in the English Lake District have been used to appraise the transferability of the Scottish, River Dee-based G-BASH model. Readily available riparian zone geochemistry and flow paths were used initially to predict minimum and mean stream water concentrations at the Nether Beck, based on calibration equations from the River Dee catchment data. Predicted values significantly exceeded observed values. Differences in runoff between the two areas, leading to a dilution effect in the Nether Beck, explained most of the difference between observed and predicted values. Greater acid deposition in the Lake District also reduced stream water Gran alkalinity concentrations in that area. If regional differences in precipitation, evapotranspiration and pollutant deposition are incorporated into the model, it may then be used reliably to predict catchment susceptibility to acidification over a wide regional (national) scale. 相似文献