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101.
Karine J. Lavergne Elizabeth C. Sharp Luc G. PelletierAlixandra Holtby 《Journal of environmental psychology》2010
Most North Americans are concerned about the environment and feel that responsibility for its protection lies primarily with government; however, no research to date has examined the influence of the government's approach toward environmental regulation on the motivation of individual citizens. According to self-determination theory, social contexts that support one's autonomy should facilitate self-determined motivation and social contexts that thwart autonomy should lead to non self-determined motivation and a sense of apathy or amotivation. In this study (n = 283), we examined the influence of perceptions of the government's approach toward environmental regulation on motivation toward the environment and frequency of self-reported pro-environmental behavior (PEB). Using structural equation modeling, we tested the hypothesis that frequency of PEB is predicted by motivation toward the environment and that motivation is predicted by the extent to which individuals perceive the government to be autonomy-supportive versus controlling in the implementation of environmental policies. The analysis revealed that perception of government autonomy-support contributed positively to autonomous motivation and negatively to amotivation, while perception of government control was positively related to both controlled motivation and amotivation. As predicted, autonomous motivation was positively, and amotivation was negatively, associated with frequency of PEB. 相似文献
102.
Methane emissions from free-ranging cattle: comparison of tracer and integrated horizontal flux techniques 总被引:1,自引:0,他引:1
Accurate measurements of methane (CH4) emission rates from livestock in their undisturbed natural environments are required to assess their impacts on radiative forcing (i.e., enhanced greenhouse effect) and the environment. Here we compare results from two nonintrusive techniques for the measurement of CH4 emissions from cattle. The cows were kept in an outdoor feeding strip that allowed them to follow natural behavioral patterns but contained them within a well defined space. In the first technique, nitrous oxide (N2O) was released as a tracer at the upwind edge of the feeding strip, and the downwind concentrations of N2O and CH4 were measured simultaneously using Fourier transform infrared (FTIR) spectroscopy. Average CH4 emission per cow was calculated each half-hour on three separate days from the correlation between the two gases. The second technique was the integrated horizontal flux (IHF) or 1-D mass-balance method, in which we used the measured vertical profiles of CH4 concentration and windspeed downwind of the cows to determine the total CH4 emission. Comparing the IHF results to the known release rate of N2O allowed us to test the IHF technique independently. We found agreement within 10% for all comparisons on all days. The daily CH4 emission rate averaged over all tracer and IHF measurements was 342 g CH4 head(-1) d(-1). This is within the range of previous measurements for mature lactating dairy cattle (200-430 g CH4 head(-1) d(-1)) but higher than expected for yearling cattle. The high CH4 emissions are accompanied by high CO2 emissions determined from the FTIR measurements. The bias is most likely due to the measurements being made during and after supplementary feeding of the cattle. 相似文献
103.
Jeremy P. Bird Robert Martin H. Reşit Akçakaya James Gilroy Ian J. Burfield Stephen T. Garnett Andy Symes Joseph Taylor Çağan H. Şekercioğlu Stuart H. M. Butchart 《Conservation biology》2020,34(5):1252-1261
Birds have been comprehensively assessed on the International Union for Conservation of Nature (IUCN) Red List more times than any other taxonomic group. However, to date, generation lengths have not been systematically estimated to scale population trends when undertaking assessments, as required by the criteria of the IUCN Red List. We compiled information from major databases of published life-history and trait data for all birds and imputed missing life-history data as a function of species traits with generalized linear mixed models. Generation lengths were derived for all species, based on our modeled values of age at first breeding, maximum longevity, and annual adult survival. The resulting generation lengths varied from 1.42 to 27.87 years (median 2.99). Most species (61%) had generation lengths <3.33 years, meaning that the period of 3 generations—over which population declines are assessed under criterion A—was <10 years, which is the value used for IUCN Red List assessments of species with short generation times. For these species, our trait-informed estimates of generation length suggested that 10 years is a robust precautionary value for threat assessment. In other cases, however, for whole families, genera, or individual species, generation length had a substantial impact on their estimated extinction risk, resulting in higher extinction risk in long-lived species than in short-lived species. Although our approach effectively addressed data gaps, generation lengths for some species may have been underestimated due to a paucity of life-history data. Overall, our results will strengthen future extinction-risk assessments and augment key databases of avian life-history and trait data. 相似文献
104.
Major shifts in Amazon wildlife populations from recent intensification of floods and drought 下载免费PDF全文
Richard Bodmer Pedro Mayor Miguel Antunez Kimberlyn Chota Tula Fang Pablo Puertas Marlini Pittet Maire Kirkland Mike Walkey Claudia Rios Pedro Perez‐Peña Peter Henderson William Bodmer Andy Bicerra Joseph Zegarra Emma Docherty 《Conservation biology》2018,32(2):333-344
In the western Amazon Basin, recent intensification of river‐level cycles has increased flooding during the wet seasons and decreased precipitation during the dry season. Greater than normal floods occurred in 2009 and in all years from 2011 to 2015 during high‐water seasons, and a drought occurred during the 2010 low‐water season. During these years, we surveyed populations of terrestrial, arboreal, and aquatic wildlife in a seasonally flooded Amazonian forest in the Loreto region of Peru (99,780 km2) to study the effects of intensification of natural climatic fluctuations on wildlife populations and in turn effects on resource use by local people. Shifts in fish and terrestrial mammal populations occurred during consecutive years of high floods and the drought of 2010. As floods intensified, terrestrial mammal populations decreased by 95%. Fish, waterfowl, and otter (Pteronura brasiliensis) abundances increased during years of intensive floods, whereas river dolphin and caiman populations had stable abundances. Arboreal species, including, macaws, game birds, primates, felids, and other arboreal mammals had stable populations and were not affected directly by high floods. The drought of 2010 had the opposite effect: fish, waterfowl, and dolphin populations decreased, and populations of terrestrial and arboreal species remained stable. Ungulates and large rodents are important sources of food and income for local people, and large declines in these animals has shifted resource use of people living in the flooded forests away from hunting to a greater reliance on fish. 相似文献
105.
106.
Marine conservation is often criticized for a mono-disciplinary approach, which delivers fragmented solutions to complex problems
with differing interpretations of success. As a means of reflecting on the breadth and range of scientific research on the
management of the marine environment, this paper develops an analytical framework to gauge the foci of policy documents and
published scientific work on Marine Protected Areas. We evaluate the extent to which MPA research articles delineate objectives
around three domains: biological-ecological [B]; economic-social[E]; and governance-management [G]. This permits us to develop
an analytic [BEG] framework which we then test on a sample of selected journal article cohorts. While the framework reveals
the dominance of biologically focussed research [B], analysis also reveals a growing frequency of the use of governance/management
terminology in the literature over the last 15 years, which may be indicative of a shift towards more integrated consideration
of governance concerns. However, consideration of the economic/social domain appears to lag behind biological and governance
concerns in both frequency and presence in MPA literature. 相似文献
107.
108.
Thomas B. Long William Young Phil Webber Andy Gouldson Helen Harwatt 《Journal of Environmental Planning and Management》2015,58(10):1853-1876
Retrofitting existing housing stock to improve energy efficiency is often required to meet climate mitigation, public health and fuel poverty targets. Increasing uptake and effectiveness of retrofit schemes requires understanding of their impacts on householder attitudes and behaviours. This paper reports results of a survey of 500 Kirklees householders in the UK, where the Kirklees Warm Zone scheme took place. This was a local government led city scale domestic retrofit programme that installed energy efficiency measures at no charge in over 50,000 houses. The results highlight key design features of the scheme, socio-economic and attitudinal factors that affected take-up of energy efficiency measures and impacts on behaviour and energy use after adoption. The results emphasise the role that positive feedback plays in reinforcing pro-environmental attitudes and behaviours of participants and in addressing concerns of non-participants. Our findings have implications for the design and operation of future domestic energy efficiency retrofit schemes. 相似文献
109.
Edward J. Brooks David W. Sims Andy J. Danylchuk Katherine A. Sloman 《Marine Biology》2013,160(10):2535-2546
The Caribbean reef shark (Carcharhinus perezi), an abundant coral-reef-associated apex predator, is one of the most economically and ecologically important, yet least studied species of large shark in the greater Caribbean region. The relative abundance and population structure of C. perezi off Cape Eleuthera, The Bahamas, was surveyed by standardised longline surveys from May 2008 to October 2011, which resulted in the capture of 331 sharks. Abundance peaked in the summer and was lowest during the winter. Females were 1.6 times more abundant than males and the assemblage was dominated by immature female sharks (45.5 %). The abundance of mature male and female sharks peaked a month apart in June and August, respectively. All 331 sharks were tagged and released with 15.4 % being recaptured after periods at liberty between 5 and 1,159 days (Mean = 333.4 ± 42.7 SE). The mean distance between tagging and recapture was 1.77 km for recaptures in excess of 6 months, indicating seasonally stratified philopatry in this species. C. perezi inhabiting Bahamian waters have developed complex habitat use patterns that are both spatiotemporally and demographically segregated, most probably in response to the large and diverse habitat mosaic available on the Bahamas Banks compared to contemporary study sites. This study represents an important step in understanding the spatiotemporal population structure of C. perezi and illustrates the potential for studies examining behavioural plasticity in response to environmental variation and anthropogenic disturbance. 相似文献
110.
Jordi Figuerola Iris Charalambidou Luis Santamaria Andy J. Green 《Die Naturwissenschaften》2010,97(6):555-565
Long distance dispersal may have important consequences for gene flow and community structure. The dispersal of many plants
depends on transport by vertebrate seed dispersers. The shapes of seed shadows produced by vertebrates depend both on movement
patterns of the dispersers and on the dynamics and effects of passage through the disperser’s gut (i.e. the retention time,
survival and germination of ingested seeds). A combination of experiments with captive waterbirds and aquatic plant seeds
was used to analyse the following: (a) the effects of inter- and intra-specific variation in seed size and duck species on
seed retention time in the gut and (b) the relationship between retention time and the percent germination and germination
rates of seeds. Among the three Scirpus species used, those with smaller seeds showed higher survival after ingestion by birds and longer retention times inside
their guts than those with larger seeds. For Potamogeton pectinatus, only seeds from the smaller size class (<8 mg) survived ingestion. Retention time affected the percent germination and germination
rate of Scirpus seeds but in a manner that varied for the different plant and bird species studied. We recorded both linear and non-linear
effects of retention time on percent germination. In addition, germination rate was positively correlated with retention time
in Scirpus litoralis but negatively correlated in Scirpus lacustris. Small seed size can favour dispersal over larger distances. However, the effects of retention time on percent germination
can modify the seed shadows produced by birds due to higher percent germination of seeds retained for short or intermediate
periods. The changes in dispersal quality associated with dispersal distance (which is expected to be positively related to
retention time) will affect the probability of seedling establishment over longer distances and, thus, the spatial characteristics
of the effective seed shadow. 相似文献