全文获取类型
收费全文 | 285篇 |
免费 | 0篇 |
国内免费 | 1篇 |
专业分类
安全科学 | 10篇 |
环保管理 | 27篇 |
综合类 | 1篇 |
基础理论 | 234篇 |
污染及防治 | 5篇 |
评价与监测 | 1篇 |
灾害及防治 | 8篇 |
出版年
2014年 | 20篇 |
2013年 | 27篇 |
2012年 | 4篇 |
2011年 | 12篇 |
2010年 | 23篇 |
2009年 | 20篇 |
2008年 | 16篇 |
2007年 | 19篇 |
2006年 | 18篇 |
2005年 | 25篇 |
2004年 | 27篇 |
2003年 | 11篇 |
2002年 | 3篇 |
2001年 | 5篇 |
2000年 | 1篇 |
1999年 | 2篇 |
1997年 | 5篇 |
1996年 | 6篇 |
1995年 | 5篇 |
1994年 | 1篇 |
1993年 | 4篇 |
1992年 | 2篇 |
1991年 | 7篇 |
1990年 | 5篇 |
1989年 | 4篇 |
1988年 | 5篇 |
1987年 | 6篇 |
1982年 | 2篇 |
1980年 | 1篇 |
排序方式: 共有286条查询结果,搜索用时 375 毫秒
211.
BENIS N. EGOH BELINDA REYERS JOSIE CARWARDINE MICHAEL BODE PATRICK J. O'FARRELL KERRIE A. WILSON HUGH P. POSSINGHAM MATHIEU ROUGET WILLEM
De LANGE DAVID M. RICHARDSON RICHARD M. COWLING 《Conservation biology》2010,24(4):1021-1030
Abstract: Global declines in biodiversity and the widespread degradation of ecosystem services have led to urgent calls to safeguard both. Responses to this urgency include calls to integrate the needs of ecosystem services and biodiversity into the design of conservation interventions. The benefits of such integration are purported to include improvements in the justification and resources available for these interventions. Nevertheless, additional costs and potential trade‐offs remain poorly understood in the design of interventions that seek to conserve biodiversity and ecosystem services. We sought to investigate the synergies and trade‐offs in safeguarding ecosystem services and biodiversity in South Africa's Little Karoo. We used data on three ecosystem services—carbon storage, water recharge, and fodder provision—and data on biodiversity to examine several conservation planning scenarios. First, we investigated the amount of each ecosystem service captured incidentally by a conservation plan to meet targets for biodiversity only while minimizing opportunity costs. We then examined the costs of adding targets for ecosystem services into this conservation plan. Finally, we explored trade‐offs between biodiversity and ecosystem service targets at a fixed cost. At least 30% of each ecosystem service was captured incidentally when all of biodiversity targets were met. By including data on ecosystem services, we increased the amount of services captured by at least 20% for all three services without additional costs. When biodiversity targets were reduced by 8%, an extra 40% of fodder provision and water recharge were obtained and 58% of carbon could be captured for the same cost. The opportunity cost (in terms of forgone production) of safeguarding 100% of the biodiversity targets was about US$500 million. Our results showed that with a small decrease in biodiversity target achievement, substantial gains for the conservation of ecosystem services can be achieved within our biodiversity priority areas for no extra cost. 相似文献
212.
A Conceptual Model for Defining and Assessing Land Management Units Using a Fuzzy Modeling Approach in GIS Environment 总被引:5,自引:0,他引:5
Appropriate land management decisions are important for current and future use of the land to ensure its sustainability. This
requires that land management units (LMUs) be specified to enable the identification of specific parameters employed in decision
making processes. This paper presents the development of a conceptual model, within geographic information systems (GIS),
for defining and assessing LMUs from available biophysical information. The model consists of two main components (sub-models):
land quality-based suitability analysis and soil erosion estimation. Using a fuzzy set methodology, the first sub-model was
constructed to derive a land suitability index (LSI) for a cropping land utilization type. The LSI thus highlights the suitability
grades of every pixel in the study area on a continuous basis. A sub-model of soil erosion was established based on the Revised
Universal Soil Loss Equation (RUSLE) utilising the same spatial data bases employed for structuring the LSI. Using a soil
loss tolerance principle, a fuzzy membership function of average annual soil loss (called soil loss index, SLI) was established,
leading to compatibility between LSI and SLI for data integration. LMUs were then derived from various combinations of LSI
and SLI. The methodology developed shows the significance of the model for refining available land suitability evaluation
systems, which take no account of expected land degradation (from erosion) due to a nominated land use. It also provides a
valuable guideline for cost-effective GIS applications in the identification and assessment of homogeneous land units, using
available spatial information sets, at a finer scale. 相似文献
213.
Scale and the Spatial Concept of Fragmentation 总被引:15,自引:0,他引:15
214.
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
215.
MICHAEL COEURDASSIER ROMAIN RIOLS ANOUK DECORS AYMERIC MIONNET FABIENNE DAVID THOMAS QUINTAINE DENIS TRUCHETET RENAUD SCHEIFLER PATRICK GIRAUDOUX 《Conservation biology》2014,28(2):315-321
In Europe, bromadiolone, an anticoagulant rodenticide authorized for plant protection, may be applied intensively in fields to control rodents. The high level of poisoning of wildlife that follows such treatments over large areas has been frequently reported. In France, bromadiolone has been used to control water voles (Arvicola terrestris) since the 1980s. Both regulation and practices of rodent control have evolved during the last 15 years to restrict the quantity of poisoned bait used by farmers. This has led to a drastic reduction of the number of cases of poisoned wildlife reported by the French surveillance network SAGIR. During the autumn and winter 2011, favorable weather conditions and high vole densities led to the staging of several hundreds of Red Kites (Milvus milvus) in the Puy‐de‐Dôme department (central France). At the same time, intensive treatments with bromadiolone were performed in this area. Although no misuse has been mentioned by the authorities following controls, 28 Red Kites and 16 Common Buzzards (Buteo buteo) were found dead during surveys in November and December 2011. For all these birds, poisoning by bromadiolone as the main cause of death was either confirmed or highly suspected. Other observations suggest a possible impact of bromadiolone on the breeding population of Red Kites in this area during the spring 2011. French regulation of vole control for plant protection is currently under revision, and we believe this event calls for more sustainable management of rodent outbreaks. Based on large‐scale experiments undertaken in eastern France, we propose that direct control of voles at low density (with trapping or limited chemical treatments) and mechanical destruction of vole tunnels, mole control, landscape management, and predator fostering be included in future regulation because such practices could help resolve conservation and agricultural issues. Envenenamiento No Intencional de Fauna Silvestre y Propuestas para un Manejo Sustentable de Roedores. 相似文献
216.
KAYCE L. CASNER MATTHEW L. FORISTER JOSHUA M. O'BRIEN JAMES THORNE DAVID WAETJEN ARTHUR M. SHAPIRO 《Conservation biology》2014,28(3):773-782
Butterfly populations are naturally patchy and undergo extinctions and recolonizations. Analyses based on more than 2 decades of data on California's Central Valley butterfly fauna show a net loss in species richness through time. We analyzed 22 years of phenological and faunistic data for butterflies to investigate patterns of species richness over time. We then used 18–22 years of data on changes in regional land use and 37 years of seasonal climate data to develop an explanatory model. The model related the effects of changes in land‐use patterns, from working landscapes (farm and ranchland) to urban and suburban landscapes, and of a changing climate on butterfly species richness. Additionally, we investigated local trends in land use and climate. A decline in the area of farmland and ranchland, an increase in minimum temperatures during the summer and maximum temperatures in the fall negatively affected net species richness, whereas increased minimum temperatures in the spring and greater precipitation in the previous summer positively affected species richness. According to the model, there was a threshold between 30% and 40% working‐landscape area below which further loss of working‐landscape area had a proportionally greater effect on butterfly richness. Some of the isolated effects of a warming climate acted in opposition to affect butterfly richness. Three of the 4 climate variables that most affected richness showed systematic trends (spring and summer mean minimum and fall mean maximum temperatures). Higher spring minimum temperatures were associated with greater species richness, whereas higher summer temperatures in the previous year and lower rainfall were linked to lower richness. Patterns of land use contributed to declines in species richness (although the pattern was not linear), but the net effect of a changing climate on butterfly richness was more difficult to discern. Contribución de la Expansión Urbana y un Clima Cambiante a la Declinación de la Fauna de Mariposas 相似文献
217.
CHAD B. WILSEY JOSHUA J. LAWLER DAVID CIMPRICH NATHAN H. SCHUMAKER 《Conservation biology》2014,28(2):561-571
Conservation‐reliant species depend on active management, even after surpassing recovery goals, for protection from persistent threats. Required management may include control of another species, habitat maintenance, or artificial recruitment. Sometimes, it can be difficult to determine whether sustained management is required. We used nonspatial stochastic population projection matrix simulation and a spatially explicit population model to estimate the effects of parasitism by a brood parasite, the Brown‐headed Cowbird (Moluthrus ater), on a population of endangered Black‐capped Vireos (Vireo atricapilla). We simulated parasitism as a percentage of breeding vireo pairs experiencing decreased fecundity due to cowbirds. We estimated maximum sustainable parasitism (i.e., highest percentage of parasitized vireo breeding pairs for which population growth is ≥1) with the nonspatial model under multiple scenarios designed to assess sensitivity to assumptions about population growth rate, demographic effects of parasitism, and spatial distribution of parasitism. We then used the spatially explicit model to estimate cumulative probabilities of the population falling below the population recovery target of 1000 breeding pairs for a range of parasitism rates under multiple scenarios. We constructed our models from data on vireos collected on the Fort Hood Military Reservation, Texas (U.S.A.). Estimates of maximum sustainable parasitism rates ranged from 9–12% in scenarios with a low (6%) vireo population growth rate to 49–60% in scenarios with a high (24%) growth rate. Sustained parasitism above 45–85%, depending on the scenario, would likely result in the Fort Hood Vireo population dropping below its recovery goal within the next 25 years. These estimates suggest that vireos, although tolerant of low parasitism rates, are a conservation‐reliant species dependent on cowbird management. Dependencia de Vireo atricapilla, Especie en Peligro, hacia el Manejo Sostenido de Moluthurs ater 相似文献
218.
Integrating Landscape and Metapopulation Modeling Approaches: Viability of the Sharp-Tailed Grouse in a Dynamic Landscape 总被引:9,自引:0,他引:9
H. REIT AKÇAKAYA VOLKER C. RADELOFF† DAVID J. MLADENOFF† HONG S. HE‡ 《Conservation biology》2004,18(2):526-537
Abstract: The lack of management experience at the landscape scale and the limited feasibility of experiments at this scale have increased the use of scenario modeling to analyze the effects of different management actions on focal species. However, current modeling approaches are poorly suited for the analysis of viability in dynamic landscapes. Demographic (e.g., metapopulation) models of species living in these landscapes do not incorporate the variability in spatial patterns of early successional habitats, and landscape models have not been linked to population viability models. We link a landscape model to a metapopulation model and demonstrate the use of this model by analyzing the effect of forest management options on the viability of the Sharp-tailed Grouse ( Tympanuchus phasianellus ) in the Pine Barrens region of northwestern Wisconsin (U.S.A.). This approach allows viability analysis based on landscape dynamics brought about by processes such as succession, disturbances, and silviculture. The landscape component of the model (LANDIS) predicts forest landscape dynamics in the form of a time series of raster maps. We combined these maps into a time series of patch structures, which formed the dynamic spatial structure of the metapopulation component (RAMAS). Our results showed that the viability of Sharp-tailed Grouse was sensitive to landscape dynamics and demographic variables such as fecundity and mortality. Ignoring the landscape dynamics gave overly optimistic results, and results based only on landscape dynamics (ignoring demography) lead to a different ranking of the management options than the ranking based on the more realistic model incorporating both landscape and demographic dynamics. Thus, models of species in dynamic landscapes must consider habitat and population dynamics simultaneously. 相似文献
219.
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
220.
Pendulum impacts on the back were conducted to determine human head, neck and torso biomechanics. Eight unembalmed cadavers were subjected to 23.4 kg pendulum impacts at 4.4 m/s and 6.6 m/s at T1 and T6. Twenty-four tests were conducted with accelerometers on the pendulum, spine, torso, and head in the WSU 3-2-2-2 array. High-speed photography was taken. Impact displaces the torso forward, deflects the chest, displaces and rotates the head, and extends the neck. Average responses and corridors were determined for head kinematics and chest force-deflection. The head-neck response occurs in two phases. First, the head displaces upwards and rearwards 30—40 mm with respect to the torso along a 45° trajectory. Head rotation is 1O°-15° with essentially no neck moment, but high neck compression forces. Second, the head rotates from 10°-15° to 40°-55° starting with a rapid rise in neck moment and displaces 80–100 mm rearward. Anterior cervical fractures correlate with neck tension. Rib fractures correlate with impact force and chest deflection. This study provides chest bio-mechanical responses for rear impacts resulting in head displacement and rotation, neck extension and cervical-thoracic injury. 相似文献