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231.
S. Mackinson G. Daskalov J.J. Heymans S. Neira H. Arancibia M. Zetina-Rejón H. Jiang H.Q. Cheng M. Coll F. Arreguin-Sanchez K. Keeble L. Shannon 《Ecological modelling》2009
Fishing mortality and primary production (or proxy for) were used to drive the dynamics of fish assemblages in 9 trophodynamic models of contrasting marine ecosystems. Historical trends in abundance were reconstructed by fitting model predictions to observations from stock assessments and fisheries independent survey data. The model fitting exercise derives values for otherwise unknown parameters that specify the relative strength of trophic interactions and, in some instances, a time series anomaly for changes in primary production. We measured how much better or worse were model predictions when bottom-up forcing by primary production were added to top-down forcing by fishing. Searching for cross system patterns, the relative contribution of fishing and changes in primary production, mediated through trophic interactions, are evaluated for the ecosystems as a whole and for selected similar species in different ecosystems. The analysis provides a simple qualitative way to explain which forcing factors have most influence on modeled dynamics. Both fishing and primary production forcing were required to obtain the best model fits to data. Fishing effects more strongly influenced 6 of 9 of the ecosystems, but primary production was more often found to be the main factor influencing the selected pelagic and demersal fish stock trends. Examination of sensitivity to ecological and model parameters suggests that the results are the product of complex food-web interactions rather than simple deterministic responses of the models. 相似文献
232.
《Environmental Communication: A Journal of Nature and Culture》2013,7(1):122-133
Recent calls for communication scholars and practitioners to identify effective communication means for mobilizing constituencies to address climate change often fall to distinguish between communicative acts that “mobilize” and mobilization that enables a particular end. The latter presupposes an account of the intentional or strategic alignment of mobilization, that is, the predicted or assumed relationships among a mobilized public, the mode(s) of influence or leverage this creates, and the expected consequences of such influence, i.e., how specific communicative efforts are related to outcomes or “effects” within a system. This essay argues that the neglect of strategic alignments in some recent climate communication campaigns have caused these campaigns to be non-adaptive at the scale and/or urgency required. Drawing on case studies of the 2007 Step It Up initiative and the Sierra Club's “Beyond Coal” campaign, the essay proposes viewing the strategic as an heuristic for identifying openings within networks of contingent relationships and the potential of certain communicative efforts to interrupt or leverage change within systems of power. 相似文献
233.
Issues in developing a capacity for integrated analysis of mitigation and adaptation 总被引:2,自引:0,他引:2
As policymakers and stakeholders increasingly consider relative merits and complementarities of climate change mitigation and adaptation strategies, it is important to improve analytical capacities to support this process. Because a single analytical approach is unlikely to fit all needs, this paper explores potentials for an integrated analytical framework that incorporates both top–down and bottom–up approaches. 相似文献
234.
Assessing the shelf life of cost‐efficient conservation plans for species at risk across gradients of agricultural land use 下载免费PDF全文
High costs of land in agricultural regions warrant spatial prioritization approaches to conservation that explicitly consider land prices to produce protected‐area networks that accomplish targets efficiently. However, land‐use changes in such regions and delays between plan design and implementation may render optimized plans obsolete before implementation occurs. To measure the shelf life of cost‐efficient conservation plans, we simulated a land‐acquisition and restoration initiative aimed at conserving species at risk in Canada's farmlands. We accounted for observed changes in land‐acquisition costs and in agricultural intensity based on censuses of agriculture taken from 1986 to 2011. For each year of data, we mapped costs and areas of conservation priority designated using Marxan. We compared plans to test for changes through time in the arrangement of high‐priority sites and in the total cost of each plan. For acquisition costs, we measured the savings from accounting for prices during site selection. Land‐acquisition costs and land‐use intensity generally rose over time independent of inflation (24–78%), although rates of change were heterogeneous through space and decreased in some areas. Accounting for spatial variation in land price lowered the cost of conservation plans by 1.73–13.9%, decreased the range of costs by 19–82%, and created unique solutions from which to choose. Despite the rise in plan costs over time, the high conservation priority of particular areas remained consistent. Delaying conservation in these critical areas may compromise what optimized conservation plans can achieve. In the case of Canadian farmland, rapid conservation action is cost‐effective, even with moderate levels of uncertainty in how to implement restoration goals. 相似文献
235.
This paper draws on the example of Tyumen Province, a federal subject of the Russian Federation, to explore the role that policies play in hindering agricultural producers’ adaptation to climate change. Its objective is to contribute to a better understanding of maladaptation at the policy level. The discourse analysis method is used to explain perceptions of climate variability in Tyumen Province and its impact on agriculture. The document analysis method is used to assess agricultural policy in Tyumen Province and its implications for producers’ adaptation to climate change. The results suggest that although agricultural producers and policymakers are acutely aware both of climate variability and the resulting loss of agricultural output, provincial agricultural policy generally fails to encourage better adaptation by agricultural producers or to support their greater economic security. Instead, it primarily focuses on meeting food production targets and thus limits the producers’ own independent moves towards adaptation. The phenomenon of maladaptation at the policy level is discussed in consideration of the general public’s and the authorities’ awareness of climate change and climate variability, and the role of science in shaping this awareness. 相似文献
236.
Anna Lyth Claudia Baldwin Aidan Davison Pedro Fidelman Kate Booth Caroline Osborne 《Local Environment》2017,22(1):1-21
The number and diversity of civil society or third sector sustainability organisations (TSSOs) have increased in recent decades. TSSOs play a prominent role in local approaches to sustainability. However, the contributions made by TSSOs are not fully understood, beyond a limited suite of quantifiable outputs and impacts. In this qualitative study, we examine how four TSSOs from two Australian regions, Tasmania and Queensland's Sunshine Coast, contribute to social transformation beyond discrete outputs. We examine the operation, ethos, scope and influence of these organisations over time. In so doing, we identify three common ways in which these organisations facilitate social change: by (i) enhancing social connectivity through boundary work; (ii) mobilising participatory citizenship and (iii) contributing to social learning. We conclude that TSSOs contribute significantly to the systemic social conditions that enable change for sustainability and the development of community resilience and well-being, but do so in ways undervalued by existing metrics, formal evaluation processes and funding models. Clearer recognition of, and strategic emphasis on, these qualitative contributions to social transformation is vital in ensuring that TSSOs remain viable and effective over the long term. 相似文献
237.
Maureen D. Correll Whitney A. Wiest Thomas P. Hodgman W. Gregory Shriver Chris S. Elphick Brian J. McGill Kathleen M. O'Brien Brian J. Olsen 《Conservation biology》2017,31(1):172-182
Coastal marshes are one of the world's most productive ecosystems. Consequently, they have been heavily used by humans for centuries, resulting in ecosystem loss. Direct human modifications such as road crossings and ditches and climatic stressors such as sea‐level rise and extreme storm events have the potential to further degrade the quantity and quality of marsh along coastlines. We used an 18‐year marsh‐bird database to generate population trends for 5 avian species (Rallus crepitans, Tringa semipalmata semipalmata, Ammodramus nelsonii subvirgatus, Ammodramus caudacutus, and Ammodramus maritimus) that breed almost exclusively in tidal marshes, and are potentially vulnerable to marsh degradation and loss as a result of anthropogenic change. We generated community and species trends across 3 spatial scales and explored possible drivers of the changes we observed, including marsh ditching, tidal restriction through road crossings, local rates of sea‐level rise, and potential for extreme flooding events. The specialist community showed negative trends in tidally restricted marshes (?2.4% annually from 1998 to 2012) but was stable in unrestricted marshes across the same period. At the species level, we found negative population trends in 3 of the 5 specialist species, ranging from ?4.2% to 9.0% annually. We suggest that tidal restriction may accelerate degradation of tidal marsh resilience to sea‐level rise by limiting sediment supply necessary for marsh accretion, resulting in specialist habitat loss in tidally restricted marshes. Based on our findings, we predict a collapse of the global population of Saltmarsh Sparrows (A. caudacutus) within the next 50 years and suggest that immediate conservation action is needed to prevent extinction of this species. We also suggest mitigation actions to restore sediment supply to coastal marshes to help sustain this ecosystem into the future. 相似文献
238.
T.R. McCLANAHAN J.E. CINNER† N.A.J. GRAHAM‡§§ T.M. DAW‡‡ J. MAINA§ S.M. STEAD‡ A. WAMUKOTA K. BROWN††‡‡ V. VENUS§ N.V.C. POLUNIN‡ 《Conservation biology》2009,23(3):662-671
Abstract: Priorities for conservation, management, and associated activities will differ based on the interplay between nearness of ecosystems to full recovery from a disturbance (pristineness), susceptibility to climate change (environmental susceptibility [ES]), and capacity of human communities to cope with and adapt to change (social adaptive capacity [AC]). We studied 24 human communities and adjacent coral reef ecosystems in 5 countries of the southwestern Indian Ocean. We used ecological measures of abundance and diversity of fishes and corals, estimated reef pristineness, and conducted socioeconomic household surveys to determine the AC of communities adjacent to selected coral reefs. We also used Web-based oceanographic and coral mortality data to predict each site's ES to climate warming. Coral reefs of Mauritius and eastern Madagascar had low ES and consequently were not predicted to be affected strongly by warm water, although these sites were differentiated by the AC of the human community. The higher AC in Mauritius may increase the chances for successful self-initiated recovery and protective management of reefs of this island. In contrast, Madagascar may require donor support to build AC as a prerequisite to preservation efforts. The Seychelles and Kenya had high ES, but their levels of AC and disturbance differed. The high AC in the Seychelles could be used to develop alternatives to dependence on coral reef resources and reduce the effects of climate change. Pristineness weighted toward measures of fish recovery was greatest for Kenya's marine protected areas; however, most protected areas in the region were far from pristine. Conservation priorities and actions with realistic chances for success require knowledge of where socioecological systems lie among the 3 axes of environment, ecology, and society. 相似文献
239.
Adaptation pathways are developed to design adaptive policies to handle climate change uncertainty. Use of this tool varies across planning practices and adaptation challenges and adjusting the tool to particular practices can foster its adequate use. To gain insight into the use of adaptation pathways, we compared four initiatives (one each in Portugal and the Czech Republic and two in the Netherlands) with regard to design choices made. We found six design choices which need to be considered when adjusting adaptation pathways. Design choices about the geographic scale, inclusion of sectors, the generation and delineation of adaptation options, specification of possible pathways, the related performance metrics and the type of assessment are interdependent, but they are also influenced by contextual aspects. Analysis of the institutional diversity, planning culture and framing shows that the use of adaptation pathways is flexible enough to be adjusted for diverging planning practices. However, the tool is best suited to deliver local adaptation solutions, and adequate use depends on consensus about the adaptation problem, setting objective thresholds and determining uncertainty about future change. We conclude that understanding the customised use of tools for local planning practices is essential for adaptive policy design. 相似文献
240.
Factors influencing support for climate mitigation policy in the United States are well researched, however, research regarding individuals’ support for climate adaptation policy is relatively sparse. This study explores how an individual’s perception of climate change impacts may influence their support for adaptation actions. Results of a survey of the U.S. public (n = 653) indicates that individuals who believe climate change impacts are unlikely to happen or will primarily affect other people in other places are less likely to be concerned about climate change impacts and less likely to support climate adaptation. However, an individual’s support for climate change adaptation measures is not influenced by their perception of when climate change impacts will occur even when taking into account concern for climate impacts. Critical for policy-makers, a belief that climate adaptation measures will not be effective attenuates the relationship between psychological distance, concern for climate change impacts, and adaptation policy measures. Our results indicate that to effectively communicate about climate change, policy-makers should emphasize that: (i) climate change impacts are occurring, (ii) that their constituents are being affected now, or will be in the future, and (iii) communicate that adaptation measures can be effective in addressing risks associated with climate change impacts. 相似文献