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271.
Abstract: Conservation of ecological processes and biodiversity may require development of a conservation system consisting of protected "cores" surrounded by "buffer zones" that effectively expand and connect the cores. Nevertheless, residential development near protected areas may threaten de facto protected areas and hinder development of an official conservation system in the United States. We identified potential conservation cores based on existing protected areas, and using a spatially explicit model of housing densities, we quantified how residential development has altered the structural context around cores nationally from 1970 to 2000 and forecasted changes from 2000 to 2030. We found that residential housing development has likely occurred preferentially near some cores, and if encroachment near cores continues at projected rates, the amount of buffer zone will have been reduced by a total of 12% by 2030, with much of this change occurring directly at core edges. Furthermore, development will have reduced the average connectedness (valence) of cores by 6% from 1970 to 2030. Although patterns of encroachment roughly increased west to east, our results painted a more complex picture of the difficulties that would be faced if establishment of an official conservation system was ever attempted. At a minimum, prioritizing future conservation action must consider adjacent land uses, and a key conservation strategy will be to work cooperatively across land-ownership boundaries, particularly for smaller protected areas, which will tend to dominate future conservation activities. 相似文献
272.
ELISE F. GRANEK STEPHEN POLASKY CARRIE V. KAPPEL DENISE J. REED DAVID M. STOMS EVAMARIA W. KOCH CHRIS J. KENNEDY LORI A. CRAMER SALLY D. HACKER EDWARD B. BARBIER SHANKAR ASWANI MARY RUCKELSHAUS GERARDO M. E. PERILLO BRIAN R. SILLIMAN NYAWIRA MUTHIGA DAVID BAEL ERIC WOLANSKI 《Conservation biology》2010,24(1):207-216
Abstract: Ecosystem-based management is logistically and politically challenging because ecosystems are inherently complex and management decisions affect a multitude of groups. Coastal ecosystems, which lie at the interface between marine and terrestrial ecosystems and provide an array of ecosystem services to different groups, aptly illustrate these challenges. Successful ecosystem-based management of coastal ecosystems requires incorporating scientific information and the knowledge and views of interested parties into the decision-making process. Estimating the provision of ecosystem services under alternative management schemes offers a systematic way to incorporate biogeophysical and socioeconomic information and the views of individuals and groups in the policy and management process. Employing ecosystem services as a common language to improve the process of ecosystem-based management presents both benefits and difficulties. Benefits include a transparent method for assessing trade-offs associated with management alternatives, a common set of facts and common currency on which to base negotiations, and improved communication among groups with competing interests or differing worldviews. Yet challenges to this approach remain, including predicting how human interventions will affect ecosystems, how such changes will affect the provision of ecosystem services, and how changes in service provision will affect the welfare of different groups in society. In a case study from Puget Sound, Washington, we illustrate the potential of applying ecosystem services as a common language for ecosystem-based management. 相似文献
273.
Current Practices and Future Opportunities for Policy on Climate Change and Invasive Species 总被引:2,自引:0,他引:2
CHRISTOPHER R. PYKE ROXANNE THOMAS† READ D. PORTER† JESSICA J. HELLMANN‡ JEFFREY S. DUKES§ DAVID M. LODGE‡ GABRIELA CHAVARRIA 《Conservation biology》2008,22(3):585-592
Abstract: Climate change and invasive species are often treated as important, but independent, issues. Nevertheless, they have strong connections: changes in climate and societal responses to climate change may exacerbate the impacts of invasive species, whereas invasive species may affect the magnitude, rate, and impact of climate change. We argue that the design and implementation of climate-change policy in the United States should specifically consider the implications for invasive species; conversely, invasive-species policy should address consequences for climate change. The development of such policies should be based on (1) characterization of interactions between invasive species and climate change, (2) identification of areas where climate-change policies could negatively affect invasive-species management, and (3) identification of areas where policies could benefit from synergies between climate change and invasive-species management. 相似文献
274.
SCOTT E. STEPHENS JOHANN A. WALKER DARIN R. BLUNCK ANEETHA JAYARAMAN DAVID E. NAUGLE JAMES K. RINGELMAN AARON J. SMITH 《Conservation biology》2008,22(5):1320-1330
Abstract: Native grasslands that support diverse populations of birds are being converted to cropland at an increasing rate in the Prairie Pothole Region of North America. Although limited funding is currently available to mitigate losses, accurate predictions of probability of conversion would increase the efficiency of conservation measures. We studied conversion of native grassland to cropland in the Missouri Coteau region of North and South Dakota (U.S.A.) during 1989–2003. We estimated the probability of conversion of native grassland to cropland with satellite imagery and logistic regression models that predicted risk of conversion and by comparing the overlap between areas of high biological value and areas most vulnerable to conversion. Annualized probability of conversion was 0.004, and 36,540 ha of native grassland were converted to cropland during the period of our study. Our predictive models fit the data and correctly predicted 70% of observed conversions of grassland. Probability of conversion varied spatially and was correlated with landscape features like amount of surrounding grassland, slope, and soil productivity. Tracts of high biological value were not always at high risk of conversion. We concluded the most biologically valuable areas that are most vulnerable to conversion should be prioritized for conservation. This approach can be applied broadly to other systems and offers great utility for implementing conservation in areas with spatially variable biological value and probability of conversion. 相似文献
275.
276.
Addressing the need for reference sites that permit wetland managers to evaluate the relative success of wetland restoration
efforts, this project examines the early successional properties of a chronosequence of 17 forested wetlands that have been
clear-cut and allowed to naturally revegetate. Ordinations performed on the data using CANOCO software indicated three general
types of communities—one dominated by bald cypress (Taxodium distichum) and water tupelo (Nyssa aquatica), one dominated by black willow (Salix nigra), and one with a species composition similar to that of a mature stand of bottomland hardwoods. These divisions were correlated
with the percentage of stems originating as coppice on stumps leftover from the clear-cut. In particular, the bottomland hardwood
stands were regenerating predominantly as coppice, while the cypress/tupelo and black willow stands were regenerating primarily
as seedlings. As indicated by the earlier development of overstory basal area, coppice sites were also regenerating much faster.
The hydrology of a site also exhibited a strong impact on the rate of regeneration, with the semipermanently to permanently
flooded portions of sites often exhibiting little or no regeneration. The results indicate that, because of the overwhelming
reliance on coppice sprouts as the main source of stems and the concomitant enhanced rates of regeneration, certain vegetative
parameters of clear-cut bottomland hardwood stands would not be effective benchmarks by which to judge the relative success
of creation and restoration efforts. 相似文献
277.
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280.
MARK R. STEVENSON PETER PALAMARA DAVID MORRISON G. ANTHONY RYAN 《Traffic injury prevention》2013,14(4):247-254
Gains in reducing mortality and morbidity from motor vehicle crashes can be achieved by understanding the behavioral factors that contribute to the elevated risk of motor vehicle-related injury and death. This study investigates the incidence, along with the effect of driver and behavioral factors, on the likelihood of motor vehicle crashes. Seventeen year old newly licensed drivers (n = 1277) in Perth, Western Australia, were recruited and followed over the first 12 months of driving. Using Cox proportional hazard analysis, driver and behavioral factors were assessed to determine whether they predicted the likelihood of a crash in the first 12 months of driving. The crash incidence rate was higher for males (1R = 4.6/10,000 driving days) than females (IR = 3.9/10,000 driving days). Multivariate analysis indicated that drivers who reported to have driven daily prior to obtaining their learners permit (L-plates) were at an increased risk of motor vehicle crash. A twofold increase in motor vehicle crash was apparent among drivers considered to be confident-adventurous drivers compared to low to moderate levels of driver confidence-adventurousness (HR = 2.04, 95% CI = 1.29-3.21). The research indicates that a driver's perception of their confidence and adventurousness in the road environment plays a part in the causal pathway leading to a motor vehicle crash. This research points to the need for preventive strategies that focus not only on knowledge and skill acquisition, but also the driver's perception in preparing young people for our roads. 相似文献