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381.
In 2016, Swedish climate reporting declined in quantity and shifted focus somewhat from climate change as such to the harmful climate impacts of meat consumption. The latter prompted discussions in social media—an increasingly important forum for public debate but infrequently studied in environmental communication research. Despite strong evidence that a meat and dairy-based diet is harmful for the environment, meat consumption is increasing, and this qualitative study aims to—through the lens of social representation theory—contribute knowledge about how livestock production is legitimized in everyday discourse on Facebook. The article identifies representations that legitimize livestock production through polarization between (1) livestock production and other (environmental) issues, (2) environmentally “good” and “bad” countries, and (3) “reliable” and “unreliable” information. It concludes by discussing the influence of national ideology on the legitimization of livestock production and the potential of social media to counter the post-politicization of environmental issues. 相似文献
382.
An Index to Measure Depreciation in Air Quality in Some Coal Mining Areas of Korba Industrial Belt of Chhattisgarh, India 总被引:1,自引:0,他引:1
Singh G 《Environmental monitoring and assessment》2006,122(1-3):309-317
The comparison with National Ambient Air Quality Standards does not always depict a true pic-ture of the Air Quality Status of a study area. As an alternative an index that measures depreciation in Air Quality on more realistic terms has been proposed and
applied to the ambient air monitoring data collected from some areas of Korba Coalfields in India. Results have been discussed in detail to illustrate the applica-tion of the proposed index and utility in bringing out more realistic air quality assessment. 相似文献
383.
This article explores individual and community action taken in response to perceived environmental risks by investigating
the determinants of environmental action across a range of action types. A conceptual framework is first presented, which
provides a foundation for investigating the role of local compositional (i.e., individual characteristics), contextual (i.e.,
neighborhood environment), and collective (i.e., social networks) factors in environmental action. To test the utility of
the conceptual framework, a quantitative survey was administered to a random sample of households (n = 512) in Hamilton, Canada.
The results suggest that the predictors of environmental action vary by action type (i.e., personal change, individual civic
action, and cooperative civic action), and that factors related to perceived environmental exposure and social capital generally
play a stronger, more consistent role in civic environmental action than sociodemographic or neighborhood factors. The results
underscore the role of social connection in responses to perceived environmental risks. 相似文献
384.
Local Responses to Inundation and De-Farming in the Reservoir Region of the Three Gorges Project (China) 总被引:1,自引:0,他引:1
Large-scale infrastructural developments in rural areas often impose significant direct and indirect impacts on environment
and people. The Three Gorges Project to dam the Yangtze River in China will create a huge reservoir, inundate farmlands and
villages, and incur large-scale resettlement. The concurrent de-farming program to reforest marginal farmlands on steep slopes
imposes additional stresses on local people. This study evaluates the ecological and economic adjustments in rural areas affected
by both projects, and explores villagers’ knowledge, attitudes, perceptions, and expectations vis-à-vis the drastic changes.
Eleven villages in Yunyang County in Sichuan Province, stratified into three zones based on topography and agriculture, were
assessed by field studies, questionnaire surveys, maps, satellite imagery, and census and government reports. Multiple regressions
identified predictors for 17 dependent variables. Spatial variations in the difficult terrain imposed zone-differentiated
agricultural constraints, ecological impacts, and human responses. The dominant farming population—mainly young adults working
as migrant laborers in cities—has adopted some nonagricultural work to supplement incomes. Expected per-capita standardized
farmland (SF) exceeded threshold SF, which surpasses existing SF. Motivations to reclaim more farmlands, de-farm marginal
lands, and become migrant laborers were explained by different multiple-regression predictors. Reduction in farmland stock
by inundation and de-farming, aggravated by unwillingness towards nonlocal resettlement, would impose ecological pressures
and stimulate demands for nonfarming incomes. Common anticipation of better future income and occupation has been subdued
by unfavorable feedbacks from early relocatees. Future environmental and landscape changes are hinged upon changing human
responses. Government policies could be informed by research findings to match economic, ecological, and social realities. 相似文献
385.
Multi-criteria assessment of socio-environmental aspects in shrinking cities. Experiences from eastern Germany 总被引:3,自引:0,他引:3
Demographic change and economic decline produce modified urban land use pattern and densities. Compared to the beginning of the 90s after the German reunification, nowadays massive housing and commercial vacancies followed by demolition and perforation come to pass in many cities of the former GDR. In consequence, a considerable surplus of urban brownfields has been created. Furthermore, the decline in the urban fabric affects social infrastructure and urban greenery of local neighbourhoods. Here, urban planning enters into ‘uncharted territory’ since it needs to assess the socio-environmental impact of shrinkage.In order to carry out such an evaluation quantitatively, a multi-criteria assessment scheme (MCA) was developed and applied. Firstly, we identified infrastructure and land use changes related to vacancy and demolition. Secondly, demolition scenarios for the coming 20 years were applied in order to give an idea for a long-term monitoring approach at the local district level. A multi-criteria indicator matrix quantifies the socio-environmental impact on both urban greenery and residents. Using it, we set demolition scenarios against urban ‘quality of life’ targets. Empirical evidence comes from Leipzig, in eastern Germany, a representative case study for urban shrinkage processes.The results show that shrinkage implies socio-environmental changes of residential livelihoods, however, does not simply increase or decrease the overall urban quality of life. The integrated assessment of all indicators identifies environmental and social opportunities, as well as the challenges a shrinking city is faced with. 相似文献
386.
Gregory E. Blomquist 《Behavioral ecology and sociobiology》2009,63(9):1345-1352
Females of many cercopithecine primates live in stable dominance hierarchies that create long-term asymmetries among sets
of female relatives (matrilines) in access to limiting resources and shelter from psychosocial stress. Rank-related differences
in fitness components are widely documented, but their causes are unclear. Predicted breeding values from an animal model
for female age of first reproduction are used to discriminate between shared additive genetic and shared environmental effects
among the members of matrilines in a population of free-ranging rhesus macaques (Macaca mulatta). While age of first reproduction has a modest heritability (≈0.2), breeding values are distributed in a largely random fashion
among matrilines and contribute little to the observed rank-related differences in average age of first reproduction. These
results support the long-held, but previously unverified, contention that rank-related life history differences in female
cercopithecine primates are the result of environmental rather than genetic differences among them. 相似文献
387.
The regulation of protein collection through pollen foraging plays an important role in pollination and in the life of bee
colonies that adjust their foraging to natural variation in pollen protein quality and temporal availability. Bumble bees
occupy a wide range of habitats from the Nearctic to the Tropics in which they play an important role as pollinators. However,
little is known about how a bumble bee colony regulates pollen collection. We manipulated protein quality and colony pollen
stores in lab-reared colonies of the native North American bumble bee, Bombus impatiens. We debut evidence that bumble bee colony foraging levels and pollen storage behavior are tuned to the protein quality (range
tested: 17–30% protein by dry mass) of pollen collected by foragers and to the amount of stored pollen inside the colony.
Pollen foraging levels (number of bees exiting the nest) significantly increased by 55%, and the frequency with which foragers
stored pollen in pots significantly increased by 233% for pollen with higher compared to lower protein quality. The number
of foragers exiting the nest significantly decreased (by 28%) when we added one pollen load equivalent each 5 min to already
high intranidal pollen stores. In addition, pollen odor pumped into the nest is sufficient to increase the number of exiting
foragers by 27%. Foragers directly inspected pollen pots at a constant rate over 24 h, presumably to assess pollen levels.
Thus, pollen stores can act as an information center regulating colony-level foraging according to pollen protein quality
and colony need.
An erratum to this article can be found at 相似文献
388.
Chemicals such as those used for scent marking, or visual cues such as color badges, can transmit information pertaining to
different aspects of individual, group and species recognition and attributes. Here, we show that complex acoustic cues, such
as calls also have the capacity for such information transfer. Although songs are usually attributed to birds, rock hyraxes
(Procavia capensis) engage in a rich and complex vocalizing behavior that we term ‘singing’. Previous studies on various species have shown
that a specific vocalization can closely reflect a specific attribute. Using a series of multiple regressions, we show that
a single complex vocalization by the adult male rock hyrax closely reflects numerous individual traits, possibly encoding
various types of biologically important information (multiple-messages hypothesis). Our study reveals that hyrax songs provide
accurate information regarding body weight, size and condition, social status and hormonal state of the singer. We also show
that these independent data are sent in a sequential manner, a pattern that probably allows a better partition of the messages
embedded in the song. Our results imply that animals, through complex individual vocalizations, can potentially advertise
multiple individual attributes in the same manner as that produced by chemical scent marking.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
389.
Informational constraints can be an important limitation on the accuracy of recognition. One potential constraint is the use
of recognition information from the same sources in multiple discriminatory contexts. Worker wood ants, Formica fusca, discriminate eggs based on their maternal sources of origin in two main contexts: recognition of eggs laid by nestmate versus
non-nestmate queens and recognition of worker-laid versus queen-laid eggs. We manipulated the experience of F. fusca workers in laboratory colonies to both worker-laid and queen-laid eggs by transferring eggs between colonies in order to
investigate whether these two contexts of egg discrimination are independent. Experience of non-nestmate queen-laid eggs significantly
increased worker acceptance of both familiar (18% accepted) and unfamiliar (10%) queen-laid eggs compared to control workers
without experience of eggs other than those laid by their own colony’s queen (2%). In contrast, worker acceptance of worker-laid
eggs was not affected by variation in the egg experience of workers (14% in workers from control colonies exposed only to
eggs from their own colony’s queen versus 19% and 17% in workers from colonies which had received eggs laid by either a non-nestmate
queen or nestmate workers, respectively). Our results suggest that these two recognition contexts do not strongly constrain
each other and are different in their ontogeny. In particular, worker-laid eggs are universally discriminated against by workers
from colonies with a queen whatever the egg experience of the workers, while non-nestmate queen-laid eggs are strongly discriminated
against only by workers without experience of eggs laid by more than one queen. 相似文献
390.
S. P. Henzi D. Lusseau T. Weingrill C. P. van Schaik L. Barrett 《Behavioral ecology and sociobiology》2009,63(7):1015-1021
There is an established and very influential view that primate societies have identifiable, persistent social organizations.
It assumes that association patterns reflect long-term strategic interests that are not qualitatively perturbed by short-term
environmental variability. We used data from two baboon troops in markedly different habitats over three consecutive seasons
to test this assumption. Our results demonstrate pronounced cyclicity in the extent to which females maintained differentiated
relationships. When food was plentiful, the companionships identified by social network analysis in the food-scarce season
disappeared and were replaced by casual acquaintanceships more representative of mere gregariousness. Data from the fourth,
food-scarce, season at one site indicated that few companions were re-united. It is likely that this reflected stochastic
variation in individual circumstances. These results suggest that attention could profitably be paid to the effects of short-term
local contingencies on social dynamics, and has implications for current theories of primate cognitive evolution.
This contribution is part of the special issue “Social Networks: new perspectives” (Guest Editors: J. Krause, D. Lusseau and
R. James). 相似文献