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701.
Ángel F. Herrera-Ulloa Anthony T. Charles Salvador E. Lluch-Cota Hermán Ramirez-Aguirre Sergio Hernández-Váquez Alfredo Ortega-Rubio 《国际发展与全球生态学杂志》2013,20(4):353-360
Sustainable development, as a multi-dimensional concept, is difficult to measure. Some efforts using indicators and indices have appeared in recent years, but most were developed on a national scale. Use of sustainability indicators has proven valuable for attaining better management of the environment by minimizing information gaps and maximizing community capabilities in terms of economic, social, environmental, and institutional sustainability dimensions. However, at least in the case of developing countries, the potential exists that national sustainability measures, based on national level indicators, may mask problems in sub-national zones with highly unsustainable conditions. This paper proposes a methodology to evaluate sustainable development at a local level, the use of which could be helpful in comparing different regions within a country or even among different countries. National sustainability indicators should result from a combination (whether additive or proportional) of regional sustainability indicators, as developed in this paper. 相似文献
702.
Veronika Holcová Jan Šíma Keith Edwards Eva Semančíková Jiří Dušek Hana Šantrůčková 《国际发展与全球生态学杂志》2013,20(5):362-367
Retention times of treated water in a constructed wetland (CW) with horizontal subsurface flow were determined both in the vegetative and non-vegetative periods of 2005. Tracer experiments were performed using fluorescein, an organic compound detectable at extremely low concentrations. Nominal and tracer retention times were determined and compared. Winter tracer retention time (TRT 194 h) and nominal retention time (nHRT 190 h) were nearly exactly equal, while summer TRT (335 h) was approximately twofold higher than nHRT (158 h). Residence time distribution function (RTD) was used to compare retention times obtained for the vegetative and non-vegetative periods. The obtained results document a significant influence of dense common reed vegetation on retention characteristics of the studied system. Common reed can convert a significant volume of water from liquid to gas via evapotranspiration (ET) and thus prolong water retention times in the system. This is very important both technically and ecologically. Longer retention times mean a longer time for microbiological decay of wastewater. Water converted from liquid to gas causes cooling of the microclimate, which is very important, especially in intensively cultivated areas with a lack of water. 相似文献
703.
Arsenic bioaccessibility in a gold mining area: a health risk assessment for children 总被引:1,自引:0,他引:1
Ono FB Guilherme LR Penido ES Carvalho GS Hale B Toujaguez R Bundschuh J 《Environmental geochemistry and health》2012,34(4):457-465
High concentrations of total arsenic (As) have been measured in soils of gold mining areas of Brazil. However, bioaccessibility tests have not yet been conducted on those materials, which is essential for better health risk estimates. This study aimed at?evaluating As bioaccessibility in samples from a gold mining area located in Brazil and assessing children's exposure to As-contaminated materials. Samples were collected from different materials (a control and four As-contaminated soils/sediments) found in a gold mine area located in Paracatu (MG), Brazil. Total and bioaccessible As concentrations were determined for all samples. The control soil presented the lowest As concentrations, while all other materials contained high total As concentrations (up to 2,666?mg?kg(-1)) and low bioaccessible As percentage (<4.2%), indicating a low risk from exposure of resident children next to this area. The calculated dose of exposure indicated that, except for the pond tailings, in all other areas, the exposure route considering soil ingestion contributed at most to 9.7% of the maximum As allowed ingestion per day (0.3?μg?kg(-1) BW day(-1)). 相似文献
704.
Gábor?HerczegEmail author László?Zsolt?Garamszegi 《Behavioral ecology and sociobiology》2012,66(1):161-169
The study of correlations between different behaviours in a population—referred to as behavioural syndromes—has begun to flourish
during recent years. However, the evolutionary mechanisms that cause behavioural traits to vary non-independently from each
other are still poorly understood. Here, we bring behavioural syndromes into a new perspective, in which the phenomenon is
regarded at the individual level and on a continuous scale instead of as a population-level presence/absence trait. As the
correlation between behaviours is never perfect (i.e. r < 1), individuals are likely to vary in how consistently they behave. Therefore, we can predict that if behavioural syndromes
at the population level are results of natural selection, the consistency in a suite of behaviours—and not the behavioural
configuration per se—should be heritable and involve fitness advantages at the individual level. We define a variable that
describes the individual deviation from the hypothetical perfect correlation predicted by the syndrome. The use of such a
variable depicting the consistency of behaviours of individuals allows us to make solid evolutionary inferences about correlated
behaviours from patterns of individual instead of population variation. We suggest that, by adopting the concept of syndrome deviation, understanding the evolution of behavioural syndromes and, in particular, testing competing evolutionary hypotheses about
the origin of behavioural syndromes becomes possible in a more rigorous manner than before. 相似文献
705.
Francisco?Santiago-QuesadaEmail author José?A.?Masero Sora?M.?Estrella Juan?M.?Sánchez-Guzmán 《Behavioral ecology and sociobiology》2012,66(3):397-405
There is a large literature dealing with daily foraging routines of wild birds during the non-breeding season. While different
laboratory studies have showed that some bird activity patterns are a persistent property of the circadian system, most of
field studies preclude the potential role of an endogenous circadian rhythm in controlling bird’s foraging routines. In this
study we compared the patterns of diurnal foraging activity and intake rates of migrating black-tailed godwits, Limosa limosa (radio-tagged and non-tagged individuals) at two stopover sites (habitats) with different environmental characteristics,
aiming at identifying proximate factors of bird activity routines. To gain insights into the role of food availability in
control of such foraging routines, we also estimated foraging activity patterns in captive godwits subjected to constant food
availability. Captive and wild black-tailed godwits showed a persistent bimodal activity pattern through daylight period.
Food availability had a significant effect on the intake rates, but had a subtler effect on foraging and intake rate rhythms.
Temperature and wind speed (combined in a weather index) showed non-significant effects on both rhythms. Although we could
not discard a role for natural diurnal changes in light intensity, an important timing cue, our findings support the idea
that an endogenous circadian rhythm could be an important proximate factor regulating foraging activity and food items taken
per unit time of wild black-tailed godwits during migration. 相似文献
706.
Ebensperger LA Sobrero R Quirici V Castro RA Tolhuysen LO Vargas F Burger JR Quispe R Villavicencio CP Vásquez RA Hayes LD 《Behavioral ecology and sociobiology》2012,66(2):261-274
Intraspecific variation in sociality is thought to reflect a trade-off between current fitness benefits and costs that emerge from individuals' decision to join or leave groups. Since those benefits and costs may be influenced by ecological conditions, ecological variation remains a major, ultimate cause of intraspecific variation in sociality. Intraspecific comparisons of mammalian sociality across populations facing different environmental conditions have not provided a consistent relationship between ecological variation and group-living. Thus, we studied two populations of the communally rearing rodent Octodon degus to determine how co-variation between sociality and ecology supports alternative ecological causes of group living. In particular, we examined how variables linked to predation risk, thermal conditions, burrowing costs, and food availability predicted temporal and population variation in sociality. Our study revealed population and temporal variation in total group size and group composition that covaried with population and yearly differences in ecology. In particular, predation risk and burrowing costs are supported as drivers of this social variation in degus. Thermal differences, food quantity and quality were not significant predictors of social group size. In contrast to between populations, social variation within populations was largely uncoupled from ecological differences. 相似文献
707.
Meredith Root-Bernstein Nicolás Arévalo Rosas Layla P. Osman Richard J. Ladle 《Journal of Coastal Conservation》2012,16(4):585-596
Coastal areas can be a challenge for conservation due to multiple competing land uses including development, tourism, and extractive resource use. These multiple land uses often lead to human-wildlife conflicts. Here we propose that collaboration with industrial designers and architects has the potential to generate innovative and effective solutions to coastal human-wildlife conflicts. Many products for modifying animal behavior are already used by conservationists, such as barriers, corridors, and model predators. We propose that their effectiveness, quality, harmonization with local values, and integration with the designed human environment can be improved through collaboration with designers and architects. We illustrate this approach with a case study. We engaged in an industrial design- conservation collaboration focused on the design of multiple product proposals that would support a range of human-sea lion interactions in public parks and the fish market in Valdivia, Chile. The sea lions in Valdivia are a tourist attraction but also potentially dangerous. We produced images of seven proposed products of varying scales, facilitating a range of different sea lion- human interactions. Such collaborations can be useful for developing products that reduce human-wildlife conflicts and align conservation and management with local values. We urge researchers to publish conservation design proposals as well as tests of existing conservation products?? functionality, in order to improve conservation design practice around the world. 相似文献
708.
Portugal is strongly vulnerable to sea hazards due to intense vessel traffic and sea conditions. The southwest region off the Iberian Peninsula lies in the main route from the Mediterranean and Southern Hemisphere to the Northern Europe, causing a ship concentration in a narrow band off Cape S?o Vicente. Tankers represent a significant part of the vessel traffic and the occurrence of oil spills cannot be disregarded. Cape S?o Vicente region is part of a Natural Park with 110 Km of coastline, integrated in the European Natura 2000 network and its socio-economic context is closely related with sea resources exploitation, particularly fishing and tourism. Recognizing the importance of accurate information systems for the decision making process in an oil spill situation, this work presents the development of an integrated tool to support the process in the Algarve coast. The system relies in a regional operational mathematical model based on the MOHID modelling system. The system core is composed by three models (3D hydrodynamics, wave and Lagrangian transport) all linked in the same system and exchanging information in real time. Oil advection and weathering processes are coupled to the Lagragian transport model. The overall operational system includes external operational data products as inputs, to ensure a successful validation of the results. The system is linked to stakeholders and response authorities using a geographic referenced database based on Mapserver technology that will include relevant information for oil spill management. 相似文献
709.
M.?C.?KrautzEmail author L.?R.?Castro M.?González J.?C.?Vera H.?E.?González 《Marine Biology》2012,159(2):303-317
In this study, we determined variations in ascorbic acid (AA) concentrations in the gonads and liver, and of the innate immune
response (lysozyme activity and antiprotease) in the plasma of Engraulis ringens (anchoveta) and Strangomera bentincki (common sardine) during their reproductive seasons of 2007 and 2008 in the central area of the Humboldt Current. During the
main spawning season in 2007, colder environmental conditions, higher phytoplankton biomasses, low dinoflagellate abundance
and the dominance of large copepods in winter-early spring and of small copepods in late spring contributed to explain higher
AA concentrations in anchoveta tissues. During the warmer year of 2008, lower phytoplankton biomasses, a notable increase
of dinoflagellate abundance and the dominance of small-size copepods in winter and of larger copepods in spring occurred along
with a drastic drop in AA concentrations in anchoveta tissues. These results contrasted with those in common sardine, a species
in which AA did not vary as much as in anchoveta. An inverse trend between AA concentration in the liver and the gonadosomatic
index suggested the AA utilization during gonadic maturation. Innate immune parameters were determined for the first time
in small pelagic fish and constitute a new baseline data to evaluate their natural response to environmental changes. Changes
in the distribution and abundance of edible taxa containing AA and edible for fish along with variations in AA in fish tissues
during their reproductive season could become good indicators of the overall fish physiological condition resulting from variations
in the trophic web structure. 相似文献
710.
The trophic ecology of Octopus vulgaris paralarvae collected in 2008 off the Ría de Vigo, NW Spain (42° 12.80′ N–9° 00.00′ W), was approached by both morphological
and molecular methods. External digestion of prey and posterior suction of the liquefied contents by wild O. vulgaris paralarvae made the morphological identification of gut contents impossible. Thus, a PCR-based method using group-specific
primers was selected to identify prey consumed by O. vulgaris paralarvae in the pelagic realm. The mitochondrial ribosomal 16S gene region was chosen for designing group-specific primers,
which targeted a broad range of crustaceans and fishes but avoided the amplification of predator DNA. These primers successfully
amplified DNA of prey by using a semi-nested PCR-based approach and posterior cloning. Homology search and phylogenetic analysis
were then conducted with the 20 different operational taxonomic units obtained to identify the putative organisms ingested.
The phylogenetic analysis clustered ingested prey into 12 families of crustaceans (11 belonging to the order Decapoda and
1 to the order Euphausiacea) and two families of fishes (Gobiidae and Carangidae). According to the Czekanowski’s Index (CI),
the trophic niche breadth of O. vulgaris paralarvae is low (CI = 0.13), which means that these paralarvae are specialist predators at least during the first weeks
of their life cycle. It is the first time that natural prey has been identified in O. vulgaris paralarvae collected from the wild, and such knowledge may be critical to increasing the survival of O. vulgaris hatchlings in captivity, a goal that has been actively pursued since the 1960s by aquaculture researchers. 相似文献