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891.
We connected a cellular, dynamic, spatial urban growth model and a semi-distributed continuous hydrology model to quantitatively predict streamflow in response to possible future urban growth at a basin scale. The main goal was to demonstrate the utility of the approach for informing public planning policy and investment choices. The Hydrological Simulation Program-Fortran (HSPF) was set up and calibrated for the Kishwaukee River basin in the Midwestern USA and was repeatedly run with various land use scenarios generated either by the urban growth model (LEAMluc) or hypothetically. The results indicate that (1) the land use scenarios generated by LEAMluc result in little changes in total runoff but some noticeable changes in surface flow; (2) the argument that low flows tend to decrease with more urbanized areas in a basin was confirmed in this study but the selection of indicators for low flows can result in misleading conclusions; (3) dynamic simulation modeling by connecting a distributed land use change model and a semi-distributed hydrological model can be a good decision support tool demanding reasonable amount of efforts and capable of long-term scenario-based assessments. 相似文献
892.
Amajirionwu M Connaughton N McCann B Moles R Bartlett J O'Regan B 《Journal of environmental management》2008,88(4):1361-1372
Sustainable development indicators (SDIs) have emerged as a tool to measure progress towards sustainable development for a number of fields. However, no indicator initiative to date has been aimed at biosolids management at local authority, regional or national levels. This paper presents a study where stakeholders involved in the management of biosolids in Ireland participated in the development of SDIs for managing biosolids at the local/regional level. A significant 81% of participating stakeholders find SDIs either 'useful' or 'very useful' as a tool for managing biosolids. A suite of 22 indicators has been developed and arranged according to the driving force-pressure-state-impact-response (DPSIR) indicator framework. The indicators address all the domains of biosolids management namely, production, quality, cost, legislation/regulation, training/research and recycling/disposal. The stakeholder approach is recognition that no effective indicator set can be developed without the input of stakeholders. 相似文献
893.
The potential impacts of land use on large woody debris (LWD) were examined in Sourdough Creek Watershed, a rapidly growing
area encompassing Bozeman, Montana, USA. We identified six land classes within a 250 m buffer extending on either side of
Sourdough Creek and assessed aquatic habitat and geomorphologic variables within each class. All LWD pieces were counted,
and we examined 14 other variables, including undercut bank, sinuosity, and substrate composition. LWD numbers were generally
low and ranged from 0 to 8.2 pieces per 50 m of stream. Linear regression showed that LWD increased with distance from headwaters,
riparian forest width, and sinuosity in four of the six land classes. Statistically significant differences between land classes
for many aquatic habitat and geomorphologic variables indicated the impacts of different land uses on stream structure. We
also found that practices such as active wood removal played a key role in LWD abundance. This finding suggests that managers
should prioritize public education and outreach concerning the importance of in-stream wood, especially in mixed-use watersheds
where wood is removed for either aesthetic reasons or to prevent stream flooding. 相似文献
894.
Brian C. Tefft Author Vitae 《Journal of Safety Research》2008,39(6):577-582
Problem
Studies have shown that older drivers have high death rates and lower rates of involvement in crashes that kill others; but most studies have not considered drivers' responsibility for their crashes, and many have considered only one particular measure of risk.Method
This study examines risks that drivers of various ages pose to themselves and to others on per-driver, per-trip, and per-mile bases, taking responsibility for crashes into account, using United States fatal crash data from 1999 through 2003 and travel estimates from 2001.Results
Relative to other age groups, drivers aged 85 and older face the highest risk of their own death, whereas teens pose the greatest risk to passengers, occupants of other vehicles, and non-motorists.Discussion
The oldest drivers pose more risk to other road users than middle-aged drivers do; the degree of their excess risk depends strongly upon how risk is measured.Impact on industry
These results demonstrate the importance of keeping clear the meaning and implications of various risk measures. 相似文献895.
Wang L Kolar P Kastner JR Herner B 《Journal of the Air & Waste Management Association (1995)》2008,58(3):412-423
Although aldehydes contribute to ozone and particulate matter formation, there has been little research on the biofiltration of these volatile organic compounds (VOCs), especially as mixtures. Biofiltration degradation kinetics of an aldehyde mixture containing hexanal, 2-methylbutanal (2-MB), and 3-methylbutanal (3-MB) was investigated using a bench-scale, synthetic, media-based biofilter. The adsorption capacity of the synthetic media for a model VOC, 3-methylbutanal, was 10 times that of compost. Periodic residence time distribution analysis (over the course of 1 yr) via a tracer study (84-99% recovery), indicated plug flow without channeling in the synthetic media and lack of compaction in the reactor. Simple first-order and zero-order kinetic models both equally fit the experimental data, yet analysis of the measured rate constants versus fractional conversion suggested an overall first-order model was more appropriate. Kinetic analysis indicated that hexanal had a significantly higher reaction rate (k = 0.09 +/- 0.005 1/sec; 23 +/- 1.3 ppmv) compared with the branched aldehydes (k = 0.04 +/- 0.0036 1/sec; 31 +/- 1.6 ppmv for 2-MB and 0.03 +/- 0.0051 1/sec; 22 +/- 1.3 ppmv for 3-MB). After 3 months of operation, all three compounds reached 100% removal (50 sec residence time, 18-46 ppmv inlet). Media samples withdrawn from the biofilter and observed under scanning electron microscopy analysis indicated microbial growth, suggesting removal of the aldehydes could be attributed to biodegradation. 相似文献
896.
Brian Byrnes∗ Clive Jones† Sandra Goodman‡ 《Journal of Environmental Planning and Management》1999,42(2):149-166
This paper presents the findings of two 'green pricing' studies conducted to evaluate public support of utilities' investments in renewable energy technologies. These studies compared hypothetical WTP statements with actual payment commitments. The results of these studies indicate that the CVM can be an accurate indicator of an individual's WTP, but that it is an unreliable predictor of which individuals will actually pay. This has important implications for aggregating mean WTP estimates of the value of environmental benefits. It also suggests that market simulations can be useful for predicting programme participation rates when voluntary donations are used as a payment vehicle. 相似文献
897.
Stream macroinvertebrate communities vary naturally among types of habitats where they are sampled, which affects the results of environmental assessment. We analyzed macroinvertebrates collected from riffle and snag habitats to evaluate influences of habitat-specific sampling on taxon occurrence, assemblage measures, and biotic indices. We found considerably more macroinvertebrate taxa unique to snags (143 taxa) than to riffles (75 taxa), and the numbers of taxa found in both riffles and snags (149 taxa) were similar to that found in snags. About 64% of the 47 macroinvertebrate measures we tested differed significantly between riffles and snags. Eighty percent intercepts of regressions between biotic indices and urban or agricultural land uses differed significantly between riffles and snags. The Hilsenhoff biotic index calculated from snag samples explained 69% of the variance of riffle samples and classified 66% of the sites into the same stream health group as the riffle samples. However, four multimetric indices for snag samples explained less than 50% of the variance of riffle samples and classified less than 50% of the sites into the same health group as the riffle samples. We concluded that macroinvertebrate indices developed for riffle/run habitat should not be used for snag samples to assess stream impairment. We recommend developing an index of biotic integrity specifically for snags and using snags as an alternate sampling substrate for streams that naturally lack riffles. 相似文献
898.
Green TJ Reeves CE Fleming ZL Brough N Rickard AR Bandy BJ Monks PS Penkett SA 《Journal of environmental monitoring : JEM》2006,8(5):530-536
This paper describes a new dual-channel PEroxy RadiCal Amplification (PERCA) instrument, which has been designed to improve the time resolution and signal to noise and to reduce the interference caused by variations in ambient ozone concentrations. The instrument was run at the Weybourne Atmospheric Observatory (WAO), North Norfolk, during WAOWEX (Weybourne Atmospheric Observatory Winter Experiment) in January/February 2002 and INSPECTRO (Influence of clouds on the spectral actinic flux in the lower troposphere) in September 2002. The performance of the instrument is assessed and compared to that of a single channel instrument. In particular, it is shown how the precision is greatly improved in fluctuating background ozone conditions. In addition the improved time response of the instrument allows changes in peroxy radical concentrations to be related to rapid changes in nitric oxide concentrations and the ozone photolysis frequency, j(O(1)D). 相似文献
899.
Project River Recovery: Restoration of Braided Gravel-Bed River Habitat in New Zealand’s High Country 总被引:1,自引:1,他引:0
Caruso BS 《Environmental management》2006,37(6):840-861
Ecological restoration is increasingly becoming a primary component of broader environmental and water resources management
programs throughout the world. The New Zealand Department of Conservation implemented Project River Recovery (PRR) in 1991
to restore unique braided gravel-bed river and wetland habitat in the Upper Waitaki Basin in New Zealand’s high country of
the South Island, which has been severely impacted by hydroelectric power development. These braided rivers are highly dynamic,
diverse, and globally important ecosystems and provide critical habitat to numerous native wading and shore bird species,
including several threatened species such as the black stilt. The objective of this study was to review and summarize PRR
after more than 10 years of implementation to provide information and transfer knowledge to other nations and restoration
programs. Site visits were conducted, discussions were held with key project staff, and project reports and related literature
were reviewed. Primary components of the program include pest plant and animal control, wetland construction and enhancement,
a significant research and monitoring component, and public awareness. The study found that PRR is an excellent example of
an ecological restoration program focusing on conserving and restoring unique habitat for threatened native bird species,
but that also includes several secondary objectives. Transfer of knowledge from PRR could benefit ecological restoration programs
in other parts of the world, particularly riverine floodplain and braided river restoration. PRR could achieve even greater
success with expanded goals, additional resources, and increased integration of science with management, especially broader
consideration of hydrologic and geomorphologic effects and restoration opportunities. 相似文献
900.
Water is scarce in many regions of the world, clean water is difficult to find in most developing countries, there are conflicts
between irrigation needs and urban demands, and there is wide debate over appropriate means of resolving these problems. Similarly,
in China, there is limited understanding of the ways in which people, groups, and institutions contribute to, are affected
by, and respond to changes in water quantity and quality. We use the example of the Yellow River basin to argue that these
social, managerial, and policy dimensions of the present water problems are significant and overshadow the physical ones.
Despite this, they receive relatively little attention in the research agenda, particularly of the lead agencies in the management
of the Yellow River basin. To this end, we ask ten research questions needed to address the policy needs of water management
in the basin, split into two groups of five. The first five relate to the importance of water in this basin and the changes
that have affected water problems and will continue to do so. The second five questions represent an attempt to explore possible
solutions to these problems. 相似文献