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141.
John A. Kronenberger Jill C. Gerberich Sarah W. Fitzpatrick E. Dale Broder Lisa M. Angeloni W. Chris Funk 《Conservation biology》2018,32(4):838-848
Human land use is fragmenting habitats worldwide and inhibiting dispersal among previously connected populations of organisms, often leading to inbreeding depression and reduced evolutionary potential in the face of rapid environmental change. To combat this augmentation of isolated populations with immigrants is sometimes used to facilitate demographic and genetic rescue. Augmentation with immigrants that are genetically and adaptively similar to the target population effectively increases population fitness, but if immigrants are very genetically or adaptively divergent, augmentation can lead to outbreeding depression. Despite well‐cited guidelines for the best practice selection of immigrant sources, often only highly divergent populations remain, and experimental tests of these riskier augmentation scenarios are essentially nonexistent. We conducted a mesocosm experiment with Trinidadian guppies (Poecilia reticulata) to test the multigenerational demographic and genetic effects of augmenting 2 target populations with 3 types of divergent immigrants. We found no evidence of demographic rescue, but we did observe genetic rescue in one population. Divergent immigrant treatments tended to maintain greater genetic diversity, abundance, and hybrid fitness than controls that received immigrants from the source used to seed the mesocosms. In the second population, divergent immigrants had a slightly negative effect in one treatment, and the benefits of augmentation were less apparent overall, likely because this population started with higher genetic diversity and a lower reproductive rate that limited genetic admixture. Our results add to a growing consensus that gene flow can increase population fitness even when immigrants are more highly divergent and may help reduce uncertainty about the use of augmentation in conservation. 相似文献
142.
The benefits of indigenous knowledge within disaster risk reduction are gradually being acknowledged and identified. However, despite this acknowledgement there continues to be a gap in reaching the right people with the correct strategies for disaster risk reduction. This paper identifies the need for a specific framework identifying how indigenous and western knowledge may be combined to mitigate against the intrinsic effects of environmental processes and therefore reduce the vulnerability of rural indigenous communities in small island developing states (SIDS) to environmental hazards. This involves a review of the impacts of environmental processes and their intrinsic effects upon rural indigenous communities in SIDS and how indigenous knowledge has contributed to their coping capacity. The paper concludes that the vulnerability of indigenous communities in SIDS to environmental hazards can only be addressed through the utilisation of both indigenous and Western knowledge in a culturally compatible and sustainable manner. 相似文献
143.
Watson SJ Taylor RS Nimmo DG Kelly LT Haslem A Clarke MF Bennett AF 《Ecological applications》2012,22(2):685-696
Fire is both a widespread natural disturbance that affects the distribution of species and a tool that can be used to manage habitats for species. Knowledge of temporal changes in the occurrence of species after fire is essential for conservation management in fire-prone environments. Two key issues are: whether postfire responses of species are idiosyncratic or if multiple species show a limited number of similar responses; and whether such responses to time since fire can predict the occurrence of species across broad spatial scales. We examined the response of bird species to time since fire in semiarid shrubland in southeastern Australia using data from surveys at 499 sites representing a 100-year chronosequence. We used nonlinear regression to model the probability of occurrence of 30 species with time since fire in two vegetation types, and compared species' responses with generalized response shapes from the literature. The occurrence of 16 species was significantly influenced by time since fire: they displayed six main responses consistent with generalized response shapes. Of these 16 species, 15 occurred more frequently in mid- or later-successional vegetation (> 20 years since fire), and only one species occurred more often in early succession (< 5 years since fire). The models had reasonable predictive ability for eight species, some predictive ability for seven species, and were little better than random for one species. Bird species displayed a limited range of responses to time since fire; thus a small set of fire ages should allow the provision of habitat for most species. Postfire successional changes extend for decades and management of the age class distribution of vegetation will need to reflect this timescale. Response curves revealed important seral stages for species and highlighted the importance of mid- to late-successional vegetation (> 20 years). Although time since fire clearly influences the distribution of numerous bird species, predictive models of the spatial distribution of species in fire-prone landscapes need to incorporate other factors in addition to time since fire. 相似文献
144.
145.
Bromide ion is rapidly converted to HOBr via BrCl by reaction with HOCl. The subsequent slow reactions of (HOCl, OCl-)/(HOBr, OBr-) mixtures are monitored directly by multiwavelength UV-vis absorbance methods and simultaneously by ion chromatographic measurement of ClO2-, ClO3-, and BrO3- (p[H+] 5.6-7.6). A first-order loss of HOCl is observed which is catalyzed by trace concentrations of Br- and BrCl. Chlorite ion forms first and is subsequently oxidized to ClO3-. The loss of HOBr is slower and is second-order in HOBr, so that BrO3- formation takes longer than ClO3- formation. Under the conditions of this work, the relative yield of BrO3- increases with increase in pH. The decomposition of HOCI by bromide proceeds primarily by a series of halogen(I) cation-transfer reactions with subsequent halide release. The presence of HOCI increases the BrO3- yield three-fold from HOBr decay alone. 相似文献
146.
García Herrero S Mariscal Saldaña MA Manzanedo del Campo MA Ritzel DO 《Journal of Safety Research》2002,33(1):1-20
This editorial reviews the evolution of the concepts of safety and quality that have been used in the traditional workplace. The traditional programs of safety are explored showing strengths and weaknesses. The concept of quality management is also viewed. Safety management and quality management principles, stages, and measurement are highlighted. The concepts of quality and safety guarantee are assessed. Total Quality Management concepts are reviewed and applied to safety quality. Total safety management principles are discussed. Finally, an analysis of the relationship between quality and safety from data collected from a company in Spain is presented. 相似文献
147.
R. Kent Jones John T. Dale 《Journal of the American Water Resources Association》1977,13(5):1007-1019
ABSTRACT: Worldwide development of water resources and control of pollution would be improved by the ability for direct, multilateral communication between workers in the dozens of different language communities involved. Current language-based problems which should be eliminated include (1) incomplete diffusion of scientific knowledge, (2) technical inbreeding, (3) unsatisfactory international conferences, (4) money wasted on translation, and (5) unstandardized technical terminology. General education in a common second language for international use can eliminate these conditions. Ethnic languages are not qualified for this purpose, because of their national biases and extreme learning difficulties. The Esperanto language is free of these limitations, and its application is recommended as a means for improving the overall performance of the industry. 相似文献
148.
Dale D. Meredith 《Journal of the American Water Resources Association》1975,11(3):526-535
ABSTRACT: The individual hydrologic components are assumed to be normally distributed for each month and linear regression equations are estimated for predicting the value of the individual monthly hydrologic components. It is shown that some of the hydrologic components for downwind (in this case downstream) lakes are dependent upon hydrologic events for the upwind lakes. This is particularly so for precipitation in the downwind lake basins which appears to be dependent upon evaporation values for upwind lakes. 相似文献
149.
Dale A. Devitt David J. Donovan Terry Katzer Michael Johnson 《Journal of the American Water Resources Association》2002,38(6):1735-1751
ABSTRACT: An essential component to the ground water budget for the Las Vegas Valley (LVV) in southern Nevada is discharge from the ground water system. Discharge for the LW has been based on estimates made more than 50 years ago of 35,524,224 m3 per year as evapotranspiration (ET) and 0 m3 per year as subsurface outflow. Newly published values for recharge based on a more robust data set (70,308,360 m3) indicate a large imbalance associated with the earlier discharge estimates, providing the basis for the reevaluation conducted in this study. ET estimates in this study, as opposed to previous studies, were assigned a range in values that included an approach that assigned higher weight to the unique soil, plant, water, and climatic conditions that existed in predevelopment (1905) LW. The earlier discharge estimates also assumed that the basin was hydrologically closed; however, based on our evaluation, a range in yearly discharge by subsurface outflow from 1,480,176 m3 to 19,735,680 m3 could be assigned. Likewise, a range in yearly ET from 20,475,768 m3 to 78,819,372 m3 could be assigned. Based on newly published recharge values, closure can only occur if higher values are assigned to both the subsurface outflow and/or ET components of ground water discharge. We cannot provide a complete water balance closure with our ground water discharge estimate of 64,140,960 m3. However our reevaluation gives support to the higher recharge estimates and provides the rationale for future studies to be conducted based on a more rigorous scientific assessment. 相似文献
150.
This paper presents the quantitative results of recent research on Canada's minerals and metals industry, and its international competitiveness for mineral investment. The information and analysis presented are derived from the work of a Canadian government-industry task force that was created in 1991, under the auspices of the Intergovernmental Working Group on the Mineral Industry (IGWG). Much of this work deals with mining taxation in several Canadian provinces. More importantly, an attempt is made to evaluate the total tax burden that the mining industry must bear, on a project basis, at all levels from exploration through refining operations in many important competitor countries. While the focus of the paper is on an international comparison of mining taxation, some non-tax issues relating to Canada's competitiveness for mineral investment are addressed . 相似文献