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Abstract: Although economic analysis can be used to argue for preservation of species and habitats, many natural assets represent inferior investments in society's asset portfolio. We demonstrate this for the case of ancient temperate rainforests and minke whales ( Balaenoptera acutorostrata ). For both rainforests and whales, we determined their value for harvest and balanced this against society's valuation of the preserved stock. For the market and nonmarket data available, we then determined how much rainforest and how many minke whales global society should keep in its asset portfolio. Although ecologists increasingly attempt to justify preservation of biological assets on economic grounds, we argue that this might be a dangerous approach to take. Ultimately, it may be necessary to reexamine the ethical foundations for conservation of nature and biodiversity, including the economist's use of utilitarianism. We suggest that the safe minimum standard approach may prove useful in practice. 相似文献
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Abstract: Illegal exploitation threatens the survival of many species, and anti-poaching legislation ("protection on paper") does not protect species. State enforcement is needed to support and supplement the formal status of endangered species, but state enforcement can be a source of instability leading to the demise of species if ad hoc rules are followed blindly. We demonstrate this with a model of poaching, wildlife, and government wildlife enforcement, but our findings apply more generally. Crucial assumptions of the dynamic model are that both poaching and enforcement effort increase or decrease whenever poaching effort and enforcement are relatively profitable or unprofitable activities, respectively. We found that multiple steady states may characterize the system's equilibrium. Depending on initial populations, the initial extent of state involvement, and random events, animal populations may be severely depleted or unexpectedly built up during transition phases. Our findings highlight the importance of history and luck in protecting endangered species. 相似文献
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Liz Root Erwin van der Krabben Tejo Spit 《Journal of Environmental Planning and Management》2015,58(4):701-718
Based on a case study of the Stadshaven port redevelopment in Rotterdam, this paper explores whether existing spatial planning mechanisms and processes can be used to facilitate local-level investment in climate-resilient public infrastructure and/or whether new processes and mechanisms are required to encourage investment in climate adaptation. The study reveals several key findings. First, a lack of conventional funding sources or formalised regulatory framework allowed room for experimentation with existing mechanisms and flexible strategies. Second, project planners are currently ambivalent towards introducing new mechanisms as a means to overcome implementation challenges. The case provides evidence about the role of the governance process, not simply as a means of system coordination that exists in isolation from institutional norms and values, but rather as a space for innovation, which can contribute towards reducing the financial gap associated with climate adaptation. 相似文献
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On the gains of committing to inefficiency: Corruption, deforestation and low land productivity in Latin America 总被引:1,自引:0,他引:1
Erwin H. Bulte Richard Damania Ramn Lpez 《Journal of Environmental Economics and Management》2007,54(3):277-295
We present a new explanation and empirical evidence showing that rural subsidies to large farmers tend to be associated with low land productivity and excessive deforestation. We develop a lobbying model where wealthy farmers trade bribes or political contributions to government politicians in exchange for subsidies; farmers are able to tilt the terms of the bargaining game with policy makers in their favor by pre-committing to an inefficient choice of semi-fixed inputs. Government proneness to accept political contributions or bribes and its willingness to provide subsidies cause farmers to adopt inefficient modes of production as a mechanism to capture such subsidies. Our predictions are consistent with stylized facts on land use in Latin America, and suggest that subsidy schemes have been counterproductive—distorting and constraining development, and triggering excessive depletion of natural resources. We validate some of the predictions of the model through econometric analyses using a new data set for nine countries in Latin America. 相似文献
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László Z. Garamszegi Thorsten J. S. Balsby Ben D. Bell Marta Borowiec Bruce E. Byers Tudor Draganoiu Marcel Eens Wolfgang Forstmeier Paolo Galeotti Diego Gil Leen Gorissen Poul Hansen Helene M. Lampe Stefan Leitner Jan Lontkowski Laurent Nagle Erwin Nemeth Rianne Pinxten Jean-Marc Rossi Nicola Saino Aurélie Tanvez Russell Titus János Török Els Van Duyse Anders P. Møller 《Behavioral ecology and sociobiology》2005,57(4):305-317
Repertoire size, the number of unique song or syllable types in the repertoire, is a widely used measure of song complexity in birds, but it is difficult to calculate this exactly in species with large repertoires. A new method of repertoire size estimation applies species richness estimation procedures from community ecology, but such capture-recapture approaches have not been much tested. Here, we establish standardized sampling schemes and estimation procedures using capture-recapture models for syllable repertoires from 18 bird species, and suggest how these may be used to tackle problems of repertoire estimation. Different models, with different assumptions regarding the heterogeneity of the use of syllable types, performed best for different species with different song organizations. For most species, models assuming heterogeneous probability of occurrence of syllables (so-called detection probability) were selected due to the presence of both rare and frequent syllables. Capture-recapture estimates of syllable repertoire size from our small sample did not differ significantly from previous estimates using larger samples of count data. However, the enumeration of syllables in 15 songs yielded significantly lower estimates than previous reports. Hence, heterogeneity in detection probability of syllables should be addressed when estimating repertoire size. This is neglected using simple enumeration procedures, but is taken into account when repertoire size is estimated by appropriate capture-recapture models adjusted for species-specific song organization characteristics. We suggest that such approaches, in combination with standardized sampling, should be applied in species with potentially large repertoire size. On the other hand, in species with small repertoire size and homogenous syllable usage, enumerations may be satisfactory. Although researchers often use repertoire size as a measure of song complexity, listeners to songs are unlikely to count entire repertoires and they may rely on other cues, such as syllable detection probability.Communicated by A. Cockburn 相似文献