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91.
Livia Dittmer Frank Mugagga Alexander Metternich Petra Schweizer-Ries George Asiimwe Manuel Riemer 《Local Environment》2018,23(2):144-157
The global dimensions of climate change necessitate a response that takes national differences – social, economic, geographic, and cultural – into account. Action-oriented education has a key role to play in advancing citizen engagement in a culture of sustainability. This paper describes research conducted with one such education programme, Youth Leading Environmental Change (YLEC), which operates in six countries and engages university-aged youth in discussion and practice related to global sustainability, systems thinking, and environmental justice. YLEC aims to advance four key competencies; this paper focuses on the goal of action competence, which involves acquiring knowledge, reflecting on experience in the context of one’s values, envisioning alternative futures, and acting individually and collectively to advance those alternatives. The present article examines the impacts of YLEC on environmental action competence in two of the countries involved in this research: Uganda and Germany. In-depth interviews were conducted with participants in both countries to examine the development of action competence during and after the programme. Findings suggest that outcomes differed in each country, reflective of participants’ different lived experiences. YLEC effectively built on the conditions faced in each country to accompany youth to a higher level of awareness and action. These findings have implications for environmental education programmes striving to work with multiple nations and diverse participants. 相似文献
92.
/ Numerous drainages supporting productive salmon habitat are surrounded by active volcanoes on the west side of Cook Inlet in south-central Alaska. Eruptions have caused massive quantities of flowing water and sediment to enter the river channels emanating from glaciers and snowfields on these volcanoes. Extensive damage to riparian and aquatic habitat has commonly resulted, and benthic macroinvertebrate and salmonid communities can be affected. Because of the economic importance of Alaska's fisheries, detrimental effects on salmonid habitat can have significant economic implications. The Drift River drains glaciers on the northern and eastern flanks of Redoubt Volcano. During and following eruptions in 1989-1990, severe physical disturbances to the habitat features of the river adversely affected the fishery. Frequent eruptions at other Cook Inlet region volcanoes exemplify the potential effects of volcanic activity on Alaska's important commercial, sport, and subsistence fisheries. Few studies have documented the recovery of aquatic habitat following volcanic eruptions. The eruptions of Redoubt Volcano in 1989-1990 offered an opportunity to examine the recovery of the macroinvertebrate community. Macroinvertebrate community composition and structure in the Drift River were similar in both undisturbed and recently disturbed sites. Additionally, macroinvertebrate samples from sites in nearby undisturbed streams were highly similar to those from some Drift River sites. This similarity and the agreement between the Drift River macroinvertebrate community composition and that predicted by a qualitative model of typical macroinvertebrate communities in glacier-fed rivers indicate that the Drift River macroinvertebrate community is recovering five years after the disturbances associated with the most recent eruptions of Redoubt Volcano. KEY WORDS: Aquatic habitat; Volcanoes; Lahars; Lahar-runout flows; Macroinvertebrates; Community structure; Community composition; Taxonomic similarity 相似文献
93.
Petra Marth Karl-Werner Schramm Bernhard Henkelmann Alexander Wolf Konstantin Oxynos Johannes Schmitzer Antonius Kettrup 《Environmental Sciences Europe》1999,11(2):89-97
For precautinary environmental protection the Environmental Specimen Bank (ESB) has been successfully established as a permanent environmental surveillance tool in Germany. The presented monitoring results on chlorinated hydrocarbons (CHC) show very clearly the effects of political decisions and can be used for the identification of pollutant sources. The CHC burden of breams (Abramis brama) from five German rivers (Elbe, Rhein, Saar, Mulde, Saale) gives an current overview of the pollution situation of different limnic ecosystems in Germany. A calculation model about the distribution of organic pollutants between different tissues offers the possibility to predict concentrations in liver and muscle of breams. Legislative emission restrictions have led to a significant decrease of dioxin levels in herring gull (Larus argentatus) eggs between 1988–1996. 相似文献
94.
95.
P. Alexander Hulley 《Marine Biology》1992,114(3):365-383
In order to determine the effects of bottom depth and water column structure on slope distributions, lanternfishes in the Cape Canyon and Cape Point Valley (eastern South Atlantic) and from the Feni Ridge and Hebridean Terrace (eastern North Atlantic) were sampled with commercial midwater nets fished 10 m above the bottom at preselected depths. Fifty-one species were taken in the eastern South Atlantic and 17 species in the eastern North Atlantic. Analyses of the samples included clustering and multi-dimensional scaling ordination of the root-root transformed densities using the Bray-Curtis similarity index. In the eastern South Atlantic (March 1988), where the horizontal and vertical temperature structuring of the water column was marked, oceanic myctophids were not taken shallower than the 300 m-depth horizon and less than one-third of the total number of species occurred inside the 500 m-depth horizon. Temperatures and bottom depths correlated with the downslope distributions of the species. Down-slope zonation was apparent. In the eastern North Atlantic (May 1983), where the temperature structure of the water column was similar at all stations, no oceanic species were taken at the 200 m-depth horizon and more than one-half of the total number of species was taken at the 300 m-depth horizon. Species distributions correlated with depth, and downslope zonation was not evident. The data sets, as well as information from the West Florida slope, suggest that both the depth and the regional temperature structure of the water column effect the upper slope distributions of oceanic myctophids. Long-slope, ribbon distribution patterns (generalized down-slope zonation) in myctophids may therefore be localized artifacts produced by the interaction of these factors. 相似文献
96.
Summary The leaf gland volatile oils of ten sweet gale plants from a Scottish population were extracted in early summer. The results differed notably from reports of other populations in respect of the sesquiterpenes, -elemenone and germacrone, which were major components of the volatile oil. Three dihydrochalcones were also detected in the volatile oil. Variation within the population existed, particularly with respect to the relative importance of germacrone. Five plants were resampled in late summer and exhibited a marked reduction in -elemenone, a lesser reduction in germacrone and changes in the proportions of some monoterpenes. 相似文献
97.
The osphradium in the genus Conus is a prominent bi-lamellate structure lying in the mantle roof near to the base of the siphon. Fine structural examination shows that the component cells are organised into a peripheral and a central region. The peripheral region consists of pigmented epidermal cells forming prominent ridges between which are grooves, at the sides of which lie the sensory cells, protected in clefts. The central region is clearly differentiated from the peripheral by a prominent basement membrane. This region contains smooth muscle, paired nerve trunks and a discrete area of cells containing numerous, dense, cored vesicles. 相似文献
98.
Kathryn E. Arnold Stephen D. Larcombe Lotta Ducaroir Lucille Alexander 《Behavioral ecology and sociobiology》2010,64(11):1857-1866
During mate choice, individuals are predicted to assess traits that honestly signal the quality of potential partners. Locomotor
capacity may be such a trait, potentially signalling condition and ability to resist oxidative damage. In this study, we experimentally
manipulated nutritional status: Male wild-type budgerigars, imported from Australia, were provided with either an enhanced
(EQ) or reduced quality (RQ) diet varying in vitamin (particularly retinol and α-tocopherol) and mineral levels. Then, we
assessed whether this influenced locomotor capacity, i.e. escape flight performance, and sexual attractiveness in male budgerigars
Melopsittacus undulatus. Males in the EQ group showed significantly greater total antioxidant capacity and higher blood plasma concentrations of the
dietary antioxidants retinol and α-tocopherol, but not carotenoids, than the RQ group. Over 8 weeks of flight training, males
on the EQ diet showed significantly greater improvement on the most strenuous flight test than RQ males. In mate choice trials,
females preferred EQ over RQ males. EQ males that were relatively fast in escape flight trials were more strongly preferred
in the mate preference arena than their RQ competitors. Interestingly, males with high plasma carotenoid levels flew slower
and were less attractive than males with low carotenoid levels. This might indicate that carotenoids are not effective antioxidants
in birds. Overall, our results show that dietary-derived antioxidants can influence sexual attractiveness and other fitness-related
traits through multiple pathways. Locomotor capacity appears to be an honest signal of male condition in birds. 相似文献
99.
Alexander K. Killion Tracy Melvin Eric Lindquist Neil H. Carter 《Conservation biology》2019,33(3):645-654
Natural resource and wildlife managers must balance the disparate priorities of a diversity of stakeholders. To manage these priorities, a firm understanding of topics salient to the public is needed. The media often report on issues of importance to the public; therefore, these reports may be a useful measure of public interest. However, efficient methods for distinguishing diverse topics related to a wildlife management issue reported in the media and changes in the salience of those topics have been lacking. We used latent Dirichlet allocation, a Bayesian mixture model, to quantitatively assess the salience of topics surrounding the gray wolf (Canis lupus), which was reintroduced to Idaho (U.S.A.) in 1995. We analyzed articles published from 1960 to 2015 in an Idaho newspaper. We identified 6 distinct topics associated with gray wolves: policy, hunting, biological status, implementation of management, recovery, and human-wolf conflict. The salience of topics pre- and postreintroduction of wolves (1995) and pre- and postdelisting of wolves from the U.S. Endangered Species Act (2009) differed significantly, underscoring that these events were turning points in how issues were being publicly discussed and framed. Articles written by the local reporters were more likely to report on topics regarding conflict between humans and wolves, whereas articles sourced from a national outlet reported more on topics pertaining to wolf policy and biological status. In the context of managing a contentious, far-ranging, and long-lived wildlife species, our methods can help guide the location and timing of a suite of management strategies (e.g., media relation plans and stakeholder engagement) that promote human-wildlife coexistence across different landscapes. 相似文献
100.
Alexander L. Metcalf Conor N. Phelan Cassandra Pallai Michael Norton Ben Yuhas James C. Finley Allyson Muth 《Conservation biology》2019,33(5):1141-1150
Widespread human action and behavior change is needed to achieve many conservation goals. Doing so at the requisite scale and pace will require the efficient delivery of outreach campaigns. Conservation gains will be greatest when efforts are directed toward places of high conservation value (or need) and tailored to critical actors. Recent strategic conservation planning has relied primarily on spatial assessments of biophysical attributes, largely ignoring the human dimensions. Elsewhere, marketers, political campaigns, and others use microtargeting—predictive analytics of big data—to identify people most likely to respond positively to particular messages or interventions. Conservationists have not yet widely capitalized on these techniques. To investigate the effectiveness of microtargeting to improve conservation, we developed a propensity model to predict restoration behavior among 203,645 private landowners in a 5,200,000 ha study area in the Chesapeake Bay Watershed (U.S.A.). To isolate the additional value microtargeting may offer beyond geospatial prioritization, we analyzed a new high-resolution land-cover data set and cadastral data to identify private owners of riparian areas needing restoration. Subsequently, we developed and evaluated a restoration propensity model based on a database of landowners who had conducted restoration in the past and those who had not (n = 4978). Model validation in a parallel database (n = 4989) showed owners with the highest scorers for propensity to conduct restoration (i.e., top decile) were over twice as likely as average landowners to have conducted restoration (135%). These results demonstrate that microtargeting techniques can dramatically increase the efficiency and efficacy of conservation programs, above and beyond the advances offered by biophysical prioritizations alone, as well as facilitate more robust research of many social–ecological systems. 相似文献