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241.
The study investigated students’ attitudes and willingness to pay (WTP) for the protection of some environmental values. The empirical study refers to a site located in Southern Italy and inserted into the Natura 2000 European Network. Students were segmented according to their appreciation of environmental values and the WTP for them. We considered two scenarios of the study site – of use and non-use – and four values – recreational, educational, bequest and existence. Five clusters, from the ‘unconcerned’ to the ‘committed’ one, reveal a diversity of profiles across the sample. Segmentation results point out the multifunctionality of the environmental heritage and highlight the heterogeneity of students’ environmental profiles. 相似文献
242.
Annie Allen 《国际发展与全球生态学杂志》2018,25(6):483-490
This paper explores challenges in reconciling the cultural, economic and ecological pillars of the sustainable development concept. It does so by examining how conflicts in the management of an island off the Irish coast called Skellig Michael, which has been internationally designated for its significant cultural and ecological attributes, have been intensified by: (a) increasing tourist numbers; (b) a re-framing of the site’s identity and (c) changing visitor motivations. These have resulted from the amplified attention the island has received following the release of Star Wars: The Force Awakens and The Last Jedi in which it features prominently. Following a critical identification and discussion of the fault lines between different stakeholders involved in the conservation and use of the island, the paper advances a roadmap for action to help resolve animosity in the governance of the site and facilitate its sustainable management in the context of changing visitor numbers and profiles. 相似文献
243.
Ryan Perkl David Mitchell Mark Feller Garrett Smith Natalie R. Wilson 《Journal of Land Use Science》2018,13(1-2):102-117
Urban and exurban expansion results in habitat and biodiversity loss globally. We hypothesize that a coupled-model approach could connect urban planning for future cities with landscape ecology to consider wildland habitat connectivity. Our work combines urban growth simulations with models of wildlife corridors to examine how species will be impacted by development to test this hypothesis. We leverage a land use change model (SLEUTH) with structural and functional landscape-connectivity modeling techniques to ascertain the spatial extent and locations of connectivity related threats to a national park in southern Arizona, USA, and describe how protected areas might be impacted by urban expansion. Results of projected growth significantly altered structural connectivity (80%) when compared to current (baseline) corridor conditions. Moreover, projected growth impacted functional connectivity differently amongst species, indicating resilience of some species and near-complete displacement of others. We propose that implementing a geospatial-design-based model will allow for a better understanding of the impacts management decisions have on wildlife populations. The application provides the potential to understand both human and environmental impacts of land-system dynamics, critical for long-term sustainability. 相似文献
244.
Tropical forest destruction and fragmentation of habitat patches may reduce population persistence at the landscape level. Given the complex nature of simultaneously evaluating the effects of these factors on biotic populations, statistical presence/absence modelling has become an important tool in conservation biology. This study uses logistic regression to evaluate the independent effects of tropical forest cover and fragmentation on bird occurrence in eastern Guatemala. Logistic regression models were constructed for 10 species with varying response to habitat alteration. Predictive variables quantified forest cover, fragmentation and their interaction at three different radii (200, 500 and 1000 m scales) of 112 points where presence of target species was determined. Most species elicited a response to the 1000 m scale, which was greater than most species’ reported territory size. Thus, their presence at the landscape scale is probably regulated by extra-territorial phenomena, such as dispersal. Although proportion of forest cover was the most important predictor of species’ presence, there was strong evidence of area-independent and -dependent fragmentation effects on species presence, results that contrast with other studies from northernmost latitudes. Species’ habitat breadth was positively correlated with AIC model values, indicating a better fit for species more restricted to tropical forest. Species with a narrower habitat breadth also elicited stronger negative responses to forest loss. Habitat breadth is thus a simple measure that can be directly related to species’ vulnerability to landscape modification. Model predictive accuracy was acceptable for 4 of 10 species, which were in turn those with narrower habitat breadths. 相似文献
245.
How simple can a model be that still captures essential aspects of wildfire ecosystems at large spatial and temporal scales? The Drossel-Schwabl model (DSM) is a metaphorical forest-fire model developed to reproduce only one pattern of real systems: a frequency distribution of fire sizes resembling a power law. Consequently, and because it appears oversimplified, it remains unclear what bearings the DSM has in reality. Here, we test whether the DSM is capable of reproducing a pattern that was not considered in its design, the hump-shaped relation between the diversity of succession stages and average annual area burnt. We found that the model, once reformulated to represent succession, produces realistic landscape diversity patterns. We investigated four succession scenarios of forest-fire ecosystems in the USA and Canada. In all scenarios, landscape diversity is highest at an intermediate average annual area burnt as predicted by the intermediate disturbance hypothesis. These results show that a model based solely on the dynamics of the fuel mosaic has surprisingly high predictive power with regard to observed statistical properties of wildfire systems at large spatial scales. Parsimonious models, such as the DSM can be used as starting points for systematic development of more structurally realistic but tractable wildfire models. Due to their simplicity they allow analytical approaches that further our understanding under increasing complexity. 相似文献
246.
The emergent behaviors of nature are not only the sum of interactions among ecosystem parts but also depend on the organization of these interactions. Fire, climate and vegetation patterns produce non-linear fire propagation across the landscape. Environmental heterogeneity, like outcrop presence and hare density, increases landscape patchiness and makes possible the occupation of fire refuges by plants, like Fabiana imbricata shrubs. We monitored shrub recruitment and cover during nine postfire years in northwestern Patagonia grasslands and we studied the long-term population dynamics under different environmental conditions through a matrix model, exploring different fire frequencies and spring precipitation regimes. Both, the field monitoring and the model seem to confirm the relationships between shrub invasion and fire. The climate change forecast predicts an increase in the frequency of El Niño Southern Oscillation phenomena that could causes more coupled fires—rainy springs in northwestern Patagonia, and consequently, more recruitment windows for shrubs, like F. imbricata. The matrix model also indicates that this scenario would be the most favourable for shrub invasion. Our results contribute to the knowledge of the ecosystem properties and processes, providing useful information to improve the grasslands sustainable use. 相似文献
247.
248.
Antarctic specially protected areas (ASPAs) are a key regulatory mechanism for protecting Antarctic environmental values. Previous evaluations of the effectiveness of the ASPA system focused on its representativeness and design characteristics, presenting a compelling rationale for its systematic revision. Upgrading the system could increase the representation of values within ASPAs, but representation alone does not guarantee the avoided loss or improvement of those values. Identifying factors that influence the effectiveness of ASPAs would inform the design and management of an ASPA system with the greatest capacity to deliver its intended conservation outcomes. To facilitate evaluations of ASPA effectiveness, we devised a research and policy agenda that includes articulating a theory of change for what outcomes ASPAs generate and how; building evaluation principles into ASPA design and designation processes; employing complementary approaches to evaluate multiple dimensions of effectiveness; and extending evaluation findings to identify and exploit drivers of positive conservation impact. Implementing these approaches will enhance the efficacy of ASPAs as a management tool, potentially leading to improved outcomes for Antarctic natural values in an era of rapid global change. Evaluación del impacto de conservación de las áreas protegidas de la Antártida 相似文献
249.
景观影响评价中"景观"的内涵和应用探讨 总被引:1,自引:0,他引:1
针对目前不同学科对于景观概念存在多种不同的解释,文章对环境影响评价中所基于的景观概念的内涵进行了探讨,指出了景观科学具有边缘性和开放性的特点。并根据目前中国景观影响评价的实际情况,提出了一些建议。 相似文献
250.
In many regions of the world, biodiversity surveys are not routinely conducted prior to activities that lead to land conversion, such as development projects. Here we use top-down methods based on global range maps and bottom-up methods based on macroecological scaling laws to illuminate the otherwise hidden biodiversity impacts of three large hydroelectric dams in the state of Sarawak in northern Borneo. Our retrospective impact assessment finds that the three reservoirs inundate habitat for 331 species of birds (3 million individuals) and 164 species of mammals (110 million individuals). A minimum of 2100 species of trees (900 million individuals) and 17 700 species of arthropods (34 billion individuals) are estimated to be affected by the dams. No extinctions of bird, mammal, or tree species are expected due to habitat loss following reservoir inundation, while 4–7 arthropod species extinctions are predicted. These assessment methods are applicable to any data-limited system undergoing land-use change.