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991.
Abstract: Ecosystem-scale networks of marine protected areas (MPAs) are important conservation tools, but their effectiveness is difficult to quantify in a time frame appropriate to species conservation because of uncertainties in the data available. The dugong ( Dugong dugon ) is a mobile marine species that occurs in shallow inshore waters of an ecosystem-scale network of MPAs (the Great Barrier Reef World Heritage Area [GBRWHA]). We developed a rapid approach to assess risk to dugongs in the region and evaluate options to ameliorate that risk. We used expert opinion and a Delphi technique to identify and rank 5 human factors with the potential to adversely affect dugongs and their sea grass habitats: netting, indigenous hunting, trawling, vessel traffic, and poor-quality terrestrial runoff. We then quantified and compared the distribution of these factors with a spatially explicit model of dugong distribution. We estimated that approximately 96% of habitat of high conservation value for dugongs in the GBRWHA is at low risk from human activities. Using a sensitivity analysis, we found that to decrease risk, commercial netting or indigenous hunting had to be reduced in remote areas and the effects of vessel traffic, terrestrial runoff, and commercial netting had to be reduced in urban areas. This approach enabled us to compare and rank risks so as to identify the most severe risks and locate specific sites that require further management attention. 相似文献
992.
LYNSEY R. PESTES RANDALL M. PETERMAN§ MICHAEL J. BRADFORD† CHRIS C. WOOD‡ 《Conservation biology》2008,22(2):351-361
Abstract: The endangered population of sockeye salmon (Oncorhynchus nerka) in Cultus Lake, British Columbia, Canada, migrates through commercial fishing areas along with other, much more abundant sockeye salmon populations, but it is not feasible to selectively harvest only the latter, abundant populations. This situation creates controversial trade-offs between recovery actions and economic revenue. We conducted a Bayesian decision analysis to evaluate options for recovery of Cultus Lake sockeye salmon. We used a stochastic population model that included 2 sources of uncertainty that are often omitted from such analyses: structural uncertainty in the magnitude of a potential Allee effect and implementation uncertainty (the deviation between targets and actual outcomes of management actions). Numerous state-dependent, time-independent management actions meet recovery objectives. These actions prescribe limitations on commercial harvest rates as a function of abundance of Cultus Lake sockeye salmon. We also quantified how much reduction in economic value of commercial harvests of the more abundant sockeye salmon populations would be expected for a given increase in the probability of recovery of the Cultus population. Such results illustrate how Bayesian decision analysis can rank options for dealing with conservation risks and can help inform trade-off discussions among decision makers and among groups that have competing objectives. 相似文献
993.
Abstract: Many ecosystems exist primarily, or solely, on privately owned (freehold) or managed (leasehold) land. In rural and semirural areas, local and regional government agencies are commonly responsible for encouraging landholders to conserve native vegetation and species on these private properties. Yet these agencies often lack the capacity to design and implement conservation programs tailored to rural and semirural landholdings and instead offer one program to all landholders. Landholders may elect not to participate because the program is irrelevant to their property or personal needs; consequently, vegetation–retention objectives may not be achieved. We differentiated landholders in Queensland, Australia, according to whether they derived income from the land (production landholders) or not (nonproduction landholders). We compared these two groups to identify similarities and differences that may inform the use of policy instruments (e.g., voluntary, economic, and regulatory) in conservation program design. We interviewed 45 landholders participating in three different conservation agreement programs (price‐based rate [property tax] rebate; market‐based tender; and voluntary, permanent covenant). Production landholders were more likely to participate in short‐term programs that offered large financial incentives that applied to <25% of their property. Nonproduction landholders were more likely to participate in long‐term programs that were voluntary or offered small financial incentives that applied to >75% of their property. These results may be explained by significant differences in the personal circumstances of production and nonproduction landholders (income, education, health) and differences in their norms (beliefs about how an individual is expected to act) and attitudes. Knowledge of these differences may allow for development of conservation programs that better meet the needs of landholders and thus increase participation in conservation programs and retention of native vegetation. 相似文献
994.
Abstract: Quantitative conservation objectives require detailed consideration of the habitat requirements of target species. Tree-living bryophytes, lichens, and fungi are a critical and declining biodiversity component of boreal forests. To understand their requirements, Bayesian methods were used to analyze the relationships between the occurrence of individual species and habitat factors at the tree and the stand scale in a naturally fragmented boreal forest landscape. The importance of unexplained between-stand variation in occurrence of species was estimated, and the ability of derived models to predict species' occurrence was tested. The occurrence of species was affected by quality of individual trees. Furthermore, the relationships between occurrence of species at the tree level and size and shape of stands indicated edge effects, implying that some species were restricted to interior habitats of large, regular stands. Yet for the habitat factors studied, requirements of many species appeared similar. Species occurrence also varied between stands; most of the seemingly suitable trees in some stands were unoccupied. The models captured most variation in species occurrence at tree level. They also successfully accounted for between-stand variation in species occurrence, thus providing realistic simulations of stand-level occupancy of species. Important unexplained between-stand variation in species occurrence warns against a simplified view that only local habitat factors influence species' occurrence. Apparently, similar stands will host populations of different sizes due to historical, spatial, and stochastic factors. Thus, habitat suitability cannot be assessed simply by population sizes, and stands lacking a species may still provide suitable habitat and merit protection. 相似文献
995.
Abstract: Conservation of wildlife is especially challenging when the targeted species damage crops or livestock, attack humans, or take fish or game. Affected communities may retaliate and destroy wildlife or their habitats. We summarize recommendations from the literature for 13 distinct types of interventions to mitigate these human–wildlife conflicts. We classified eight types as direct (reducing the severity or frequency of encounters with wildlife) and five as indirect (raising human tolerance for encounters with wildlife) interventions. We analyzed general cause‐and‐effect relationships underlying human–wildlife conflicts to clarify the focal point of intervention for each type. To organize the recommendations on interventions we used three standard criteria for feasibility: cost‐effective design, wildlife specificity and selectivity, and sociopolitical acceptability. The literature review and the feasibility criteria were integrated as decision support tools in three multistakeholder workshops. The workshops validated and refined our criteria and helped the participants select interventions. Our approach to planning interventions is systematic, uses standard criteria, and optimizes the participation of experts, policy makers, and affected communities. We argue that conservation action generally will be more effective if the relative merits of alternative interventions are evaluated in an explicit, systematic, and participatory manner. 相似文献
996.
Knowing how much biodiversity is captured by protected areas (PAs) is important to meeting country commitments to international conservation agreements, such as the Convention on Biological Diversity, and analyzing gaps in species coverage by PAs contributes greatly to improved locating of new PAs and conservation of species. Regardless of their importance, global gap analyses have been conducted only for a few taxonomic groups (e.g., mangroves, corals, amphibians, birds, mammals). We conducted the first global gap analysis for a complete specious plant group, the highly threatened Cactaceae. Using geographic distribution data of 1438 cactus species, we assessed how well the current PA network represents them. We also systematically identified priority areas for conservation of cactus species that met and failed to meet conservation targets accounting for their conservation status. There were 261 species with no coverage by PAs (gap species). A greater percentage of cacti species (18%) lacked protection than mammals (9.7%) and birds (5.6%), and also a greater percentage of threatened cacti species (32%) were outside protected areas than amphibians (26.5%), birds (19.9%), or mammals (16%). The top 17% of the landscape that best captured covered species represented on average 52.9% of species ranges. The priority areas for gap species and the unprotected portion of the ranges of species that only partially met their conservation target (i.e., partial gap) captured on average 75.2% of their ranges, of which 100 were threatened gap species. These findings and knowledge of the threats affecting species provide information that can be used to improve planning for cacti conservation and highlight the importance of assessing the representation of major groups, such as plants, in PAs to determining the performance of the current PA network. 相似文献
997.
Global demand for elephant ivory is contributing to illegal poaching and significant decline of African elephant (Loxondonta africana) populations. To help mitigate decline, countries with legal domestic ivory markets were recommended by the Convention on International Trade in Endangered Species of Wild Fauna and Flora to close domestic markets for commercial trade. However, implementing stricter regulations on wildlife trade does not necessarily mean compliance with rules will follow. Using an online questionnaire, we examined the relationship between self-reported compliance with ivory trade regulations among 115 ivory traders in the United Kingdom and 4 dimensions (control, deterrence, legitimacy, and social norms) hypothesized to influence compliance with conservation regulations. Although most traders supported regulations, a large number did not always check that they comply with them when trading objects containing ivory. The main factors influencing compliance with ivory trade regulations were traders’ ability to comply and their perceptions of the regulations and punishments to deter illegal trade. These findings demonstrate the utility of conservation criminology to improve wildlife trade regulations and identify opportunities to reduce illegal ivory entering the market in the United Kingdom. Compliance could be improved by clearer regulations that facilitate easier detection of illegal ivory products and stronger prosecution of violations. 相似文献
998.
Social marketing campaigns use marketing techniques to influence human behavior for the greater social good. In the conservation sector, social marketing campaigns have been used to influence behavior for the benefit of biodiversity as well as society. However, there are few evaluations of their effectiveness. We devised an approach for evaluating the influences of social marketing campaigns on human behavior and conservation outcomes. We used general elimination methodology, a theory-driven qualitative evaluation method, to assess the long-term impacts of a 1998 Rare Pride campaign on the island of Bonaire that was designed to increase the population of the Lora (Amazona barbadensis), a threatened parrot. We interviewed stakeholder groups to determine their perceptions of the drivers of the changes in the Lora population over time. We used these data to develop an overall theory of change to explain changes in the Lora population by looking at the overlap in hypotheses within and between stakeholder groups. We then triangulated that theory of change with evidence from government reports, peer-reviewed literature, and newspapers. The increase in the Lora population was largely attributed to a decrease in illegal poaching of Loras and an associated decrease in local demand for pet Loras. Decreases in poaching and demand were likely driven by a combination of law enforcement, social marketing (including the Rare campaign), and environmental education in schools. General elimination methodology helped show how multiple interventions influenced a conservation outcome over time. There is a need for evidence-based evaluations of social marketing interventions to ensure that limited resources are spent wisely. 相似文献
999.
Sara H. Williams Sarah A. Scriven David F. R. P. Burslem Jane K. Hill Glen Reynolds Agnes L. Agama Frederick Kugan Colin R. Maycock Eyen Khoo Alexander Y. L. Hastie John B. Sugau Reuben Nilus Joan T. Pereira Sandy L. T. Tsen Leung Y. Lee Suzika Juiling Jenny A. Hodgson Lydia E. S. Cole Gregory P. Asner Luke J. Evans Jedediah F. Brodie 《Conservation biology》2020,34(4):934-942
Conservation planning tends to focus on protecting species’ ranges or landscape connectivity but seldom both—particularly in the case of diverse taxonomic assemblages and multiple planning goals. Therefore, information on potential trade-offs between maintaining landscape connectivity and achieving other conservation objectives is lacking. We developed an optimization approach to prioritize the maximal protection of species’ ranges, ecosystem types, and forest carbon stocks, while also including habitat connectivity for range-shifting species and dispersal corridors to link protected area. We applied our approach to Sabah, Malaysia, where the state government mandated an increase in protected-area coverage of approximately 305,000 ha but did not specify where new protected areas should be. Compared with a conservation planning approach that did not incorporate the 2 connectivity features, our approach increased the protection of dispersal corridors and elevational connectivity by 13% and 21%, respectively. Coverage of vertebrate and plant species’ ranges and forest types were the same whether connectivity was included or excluded. Our approach protected 2% less forest carbon and 3% less butterfly range than when connectivity features were not included. Hence, the inclusion of connectivity into conservation planning can generate large increases in the protection of landscape connectivity with minimal loss of representation of other conservation targets. 相似文献
1000.
Danielle Tessaro 《国际发展与全球生态学杂志》2013,20(5):471-479
In South Africa, extreme rural poverty often geographically overlaps with areas of high and important biodiversity. Attempts to bring about land-based poverty reduction projects in such areas tends to trigger tensions among stakeholders purporting to be concerned about local people’s welfare, as well as the environment. Using discursive document analysis and semi-structured interviews, the paper discusses a case study of the Wild Coast, an area celebrated for its high biodiversity and ‘beauty’, which reveals that a tension among environmental non-government organisations, government agencies and the private sector, on the best development option, exacerbates the threats to local livelihood options and biodiversity conservation. 相似文献