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131.
随着深圳市城市发展步伐的不断加快,福田红树林自然保护区受到水体污染、人为干扰、病虫害及外来物种等各方面影响,导致其生态系统出现不同程度的退化。通过赴香港米埔自然保护区考察与学习,分析了香港米埔自然保护区精细化管理、生态系统日趋稳定及教育宣传等经验,提出了深圳福田乃至全国红树林自然保护区保护与管理对策和建议。  相似文献   
132.
Helen Hazen 《Geoforum》2008,39(1):252-264
This paper explores the operation of the international World Heritage Convention in the national context of the United States. Although an early advocate of the national park idea and among the earliest proponents of the Convention, the US has shown increasing ambivalence towards the World Heritage Program since the mid-1990s. Through in-depth interviews with expert informants and a questionnaire survey of 406 visitors at four US World Heritage Sites, this study considers whether combining national and international conservation designations provides valuable reinforcement of conservation goals, or leads to unnecessary overlap and even challenges to sovereignty. The majority of my expert informants were supportive of the Convention, related to philosophical and practical benefits that they believed to be associated with the World Heritage label, although most identified few tangible influences of the World Heritage Program itself. Several noted hostility to the Program from a nationalist fringe, which fears international involvement in land use decisions. Such concerns were reflected in questionnaire responses, which revealed some distrust of the Convention and misunderstandings of its operation. I conclude that the scalar mismatch of implementing an international convention at the national scale inevitably involves challenges, but that country-specific factors are important in explaining why the Convention has been particularly controversial in the US. Education is integral to addressing these challenges, as well as reengagement with the Program by both the National Park Service and the federal administration. Intangible values associated with World Heritage mean that the Convention still enjoys considerable support in the US, providing a solid foundation for such a reengagement.  相似文献   
133.
Q methodology provides a novel, quantitative approach to reveal stakeholder perspectives and was used to assess social acceptance of Marine Protected Areas (MPAs) with fisheries and conservation management goals using the Devon & Severn region, UK as a case study site. Participants sorted a set of statements (n=42) into a forced-choice frequency distribution and centroid analysis revealed three factors for interpretation: (1) ‘pro-conservation’, characterised by views that conservation should be prioritised over commercial and economic interests; (2) ‘pro-fisheries’ who saw fishing as the priority and expressed concerns over the uncertainty of management measures and the number of planned MPAs; and (3) ‘win–win’ who felt that the current approach to marine management using MPAs would allow both fisheries and conservation goals to be met. Despite some differences in opinion, social acceptability of MPAs was identified across all three discourses, but was limited by the knock-on effects of the exclusion of stakeholders from the implementation of MPAs and the development of management measures. This resulted in disenfranchisement and uncertainty over the future of their activities. The results suggest that social acceptability of MPAs is generated by effective and ongoing stakeholder engagement, transparency and honesty relating to the costs and benefits of designations and a certainty that once sites are in place the resources exist for their effective management. Understanding social acceptability will guide adaptive management and increase the chances of MPA success and the meeting of global targets.  相似文献   
134.
Skates (Rajidae) have been commercially exploited in Europe for hundreds of years with some species’ abundances declining dramatically during the twentieth century. In 2009 it became “prohibited for EU vessels to target, retain, tranship or land” certain species in some ICES areas, including the critically endangered common skate and the endangered white skate. To examine compliance with skate bans the official UK landings data for 2011–2014 were analysed. Surprisingly, it was found that after the ban prohibited species were still reported landed in UK ports, including 9.6 t of common skate during 2011–2014. The majority of reported landings of common and white skate were from northern UK waters and landed into northern UK ports. Although past landings could not be validated as being actual prohibited species, the landings’ patterns found reflect known abundance distributions that suggest actual landings were made, rather than sporadic occurrence across ports that would be evident if landings were solely due to systematic misidentification or data entry errors. Nevertheless, misreporting and data entry errors could not be discounted as factors contributing to the recorded landings of prohibited species. These findings raise questions about the efficacy of current systems to police skate landings to ensure prohibited species remain protected. By identifying UK ports with the highest apparent landings of prohibited species and those still landing species grouped as'skates and rays’, these results may aid authorities in allocating limited resources more effectively to reduce landings, misreporting and data errors of prohibited species, and increase species-specific landing compliance.  相似文献   
135.
The giant tortoises of the Galápagos Islands, a species Charles Darwin called ‘antediluvian,’ are the focus of one of the world’s most successful conservation breeding programs. This paper explores the paradox of the breeding program, examining how ‘prehistoric’ life has been actively produced through nearly a century of work by scientists and conservationists dedicated to saving this endangered species. It traces the story of one giant tortoise, Diego, who was collected from the archipelago in the 1930s, lived in an colony at the San Diego Zoo for forty years, and returned to the Galápagos in 1977, where he became the star stud of the breeding program. I argue that the giant tortoises are not icons of a ‘pristine’ evolutionary history, but are the product of genealogies that enfold management practices in the bodies and bloodlines of wildlife. The paper focuses on the assemblages of reproduction at the center of these genealogies, drawing attention to the multiple agencies and spatialities that emerge in practices of experimentation – first at the zoo, where keepers struggled to keep the giant tortoise colony alive and healthy, and then in the Galápagos, where conservationists were eventually able to gain enough control over tortoise reproduction to standardize and replicate breeding practices. The case extends readings of conservation as a field of nonhuman biopolitics by attending to the production of wildlife itself as a strategy that facilitates the reproduction of conservation and tourism in the archipelago.  相似文献   
136.
 The economic benefits of the adoption of conservation tillage depend on site-specific factors including soil characteristics, local climatic conditions, cropping patterns, and other attributes of the overall farming operation. While it is possible to draw some general inferences about components of economic returns and costs, a comprehensive assessment of the net private benefits from greater use of conservation tillage is not feasible. Received: 4 December 1997 · Accepted: 30 March 1998  相似文献   
137.
ABSTRACT

Forest and agricultural sector response to comprehensive climate policy is well represented in the literature. Less analysis has been devoted to piecemeal solutions. We use the Forest and Agriculture Sector Optimization Model with Greenhouse Gases (FASOMGHG) to project the individual and combined effect of three existing U.S. Department of Agriculture programmes with potential to increase greenhouse gas (GHG) mitigation. We find that a combined policy scenario may achieve greater mitigation than individual constituent programmes, suggesting the possibility of complementary spillover effects in some periods. Mitigation varies over time, however, and some periods experience net emissions as markets and management practices respond to initial policy shocks. The regional distribution of GHG mitigation also varies between policy scenario. Differences in the magnitude and imputed cost of mitigation under each scenario, generating negative values for some programmes and time periods, reinforces the need to evaluate portfolio design to cost-effectively achieve near-term GHG mitigation.

Key policy insights
  • Increased near-term GHG mitigation in the forest and agriculture sectors in the US may be possible by expanding or refocusing the emphasis of existing programmes.

  • Implementing several such forest and agricultural programmes simultaneously may lead to greater GHG mitigation than when implemented separately, indicating the possibility of positive spillover effects.

  • Programmes targeted to agricultural management may hold outsized potential to achieve near-term GHG mitigation; Policies aimed at influencing land use conversion appear to be more vulnerable to reversion and subject to larger inter-annual swings.

  • The staged implementation of programmes could also be useful, helping to encourage increased mitigation (or the retention of already achieved mitigation) over time as markets re-equilibrate to initial shocks.

  • Though the particular scenarios assessed here are unique to the US, our findings may be applicable to other locations outside the US where land management is influenced by individual market actors and there is competition between forest and agricultural land uses.

  相似文献   
138.
Encouraging pro-environmental behavior is an urgent global challenge. An interdisciplinary framework covering governance, economic, social, ecological, and psychological dimensions is required to understand the salient features that encourage pro-environmental outcomes within and across contexts. We apply the Ostrom social-ecological systems framework to model voluntary investments by members of civil society into the aquatic environment. Using a data set of 1,809 angling clubs managing water bodies for fish stocking and habitat management in Germany and France, we show that a small set of factors, most crucially social-ecological and governance context as well as social norms and other bottom-up social pressures, drive environmental investments. These factors appear to override behavioral influences from psychological variables of the decision-maker. By contrast, the contextual setting related to property rights, size of the resource system, and social expectations were found to be strongly related to behavioral decisions, highlighting that the social-ecological context as well as incentives may be more important than knowledge and cognitions in driving certain pro-environmental actions.  相似文献   
139.
The adoption of endangered species laws in various nations has intensified efforts to better understand, and protect, at-risk species or populations, and their habitats. In many countries, delineating a portion of a species' habitat as particularly worthy of protection has become a mantra of these laws. Unfortunately, the laws themselves often provide scientists and managers with few, if any, guidelines for how to define such habitat. Conservationists and scientists may view protecting part of the habitat of an endangered species as an ineffectual compromise, while managers may be under pressure to allow a range of human activities within the species' habitat. In the case of small cetaceans, establishing boundaries for such areas can also be complicated by their mobility, the fluid nature of their environment, and the often ephemeral nature of their habitat features. The convergence of multiple human impacts in coastal waters around the world is impacting many small cetaceans (and other species) that rely on these areas for feeding, reproducing, and resting. The ten guiding principles presented here provide a means to characterize the habitat needs of small, at-risk cetaceans, and serve as a basis for the delineation of ‘priority habitat’ boundaries. This conceptual approach should facilitate a constructive discourse between scientists and managers engaged in efforts to recover endangered species. The degree to which the recovery of an at-risk species can be reconciled with sustainable economic activity will depend in part on how well these principles are incorporated into the delineation of priority habitat.  相似文献   
140.
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