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131.
崇义客家梯田生态系统服务功能 总被引:3,自引:0,他引:3
开展崇义客家梯田系统生态服务功能价值评估,有助于人们更好地了解梯田系统对崇义客家社会的重要贡献,为当地政府保护客家梯田系统提供重要依据.本研究基于崇义客家梯田系统及其所处区域的社会经济特征,构建了相应的生态服务功能价值评估指标体系;运用定性分析法对客家梯田系统的生态服务功能机理及其重要性作了识别;以2014年统计数据为基础,采用物质量和价值量相结合的定量评价方法,对客家梯田系统的9项生态服务指标进行评估.结果表明: 在评估的9项指标中,土壤保持的物质量和价值量同居各指标之首,分别为76457 kg·hm-2和105033 元·hm-2,相应地占梯田系统总物质量和总价质量的72.2%和30.0%.文化传承和景观体现了客家梯田系统独特的生态服务功能,价值量分别为100000和46333元·hm-2,位居9项指标的2、3位.产品供给是客家梯田系统提供给崇义客家人的重要福祉,但其物质量和价值量只占梯田系统生态服务总物质量和总价值量的6.1%与10.4%,因此仅考虑产品供给将严重低估梯田系统的生态服务功能.直观的经济数字反映了客家梯田系统对社会的巨大贡献,不仅有利于提高管理者和公众保护农业文化遗产的意识,也为政府制定客家梯田系统生态补偿标准提供了数据支撑. 相似文献
132.
PAUL S. GILLER 《Journal of Applied Ecology》2005,42(2):201-207
133.
Romano P 《Briefings in bioinformatics》2008,9(1):57-68
Data integration is needed in order to cope with the huge amounts of biological information now available and to perform data mining effectively. Current data integration systems have strict limitations, mainly due to the number of resources, their size and frequency of updates, their heterogeneity and distribution on the Internet. Integration must therefore be achieved by accessing network services through flexible and extensible data integration and analysis network tools. EXtensible Markup Language (XML), Web Services and Workflow Management Systems (WMS) can support the creation and deployment of such systems. Many XML languages and Web Services for bioinformatics have already been designed and implemented and some WMS have been proposed. In this article, we review a methodology for data integration in biomedical research that is based on these technologies. We also briefly describe some of the available WMS and discuss the current limitations of this methodology and the ways in which they can be overcome. 相似文献
134.
Agricultural sustainability: concepts, principles and evidence 总被引:1,自引:0,他引:1
Pretty J 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2008,363(1491):447-465
Concerns about sustainability in agricultural systems centre on the need to develop technologies and practices that do not have adverse effects on environmental goods and services, are accessible to and effective for farmers, and lead to improvements in food productivity. Despite great progress in agricultural productivity in the past half-century, with crop and livestock productivity strongly driven by increased use of fertilizers, irrigation water, agricultural machinery, pesticides and land, it would be over-optimistic to assume that these relationships will remain linear in the future. New approaches are needed that will integrate biological and ecological processes into food production, minimize the use of those non-renewable inputs that cause harm to the environment or to the health of farmers and consumers, make productive use of the knowledge and skills of farmers, so substituting human capital for costly external inputs, and make productive use of people's collective capacities to work together to solve common agricultural and natural resource problems, such as for pest, watershed, irrigation, forest and credit management. These principles help to build important capital assets for agricultural systems: natural; social; human; physical; and financial capital. Improving natural capital is a central aim, and dividends can come from making the best use of the genotypes of crops and animals and the ecological conditions under which they are grown or raised. Agricultural sustainability suggests a focus on both genotype improvements through the full range of modern biological approaches and improved understanding of the benefits of ecological and agronomic management, manipulation and redesign. The ecological management of agroecosystems that addresses energy flows, nutrient cycling, population-regulating mechanisms and system resilience can lead to the redesign of agriculture at a landscape scale. Sustainable agriculture outcomes can be positive for food productivity, reduced pesticide use and carbon balances. Significant challenges, however, remain to develop national and international policies to support the wider emergence of more sustainable forms of agricultural production across both industrialized and developing countries. 相似文献
135.
Chacoff NP Aizen MA Aschero V 《Proceedings. Biological sciences / The Royal Society》2008,275(1637):907-913
A decline in pollination function has been linked to agriculture expansion and intensification. In northwest Argentina, pollinator visits to grapefruit, a self-compatible but pollinator-dependent crop, decline by approximately 50% at 1km from forest edges. We evaluated whether this decrease in visitation also reduces the pollination service in this crop. We analysed the quantity and quality of pollen deposited on stigmas, and associated limitation of fruit production at increasing distances (edge: 10, 100, 500 and 1000m) from the remnants of Yungas forest. We also examined the quantitative and qualitative efficiency of honeybees as pollen vectors. Pollen receipt and pollen tubes in styles decreased with increasing distance from forest edge; however, this decline did not affect fruit production. Supplementation of natural pollen with self- and cross-pollen revealed that both pollen quantity and quality limited fruit production. Despite pollen limitation, honeybees cannot raise fruit production because they often do not deposit sufficient high-quality pollen per visit to elicit fruit development. However, declines in visitation frequency well below seven visits during a flower's lifespan could decrease production beyond current yields. In this context, the preservation of forest remnants, which act as pollinator sources, could contribute to resilience in crop production. Like wild plants, pollen limitation of the yield among animal-pollinated crops may be common and indicative not only of pollinator scarcity, but also of poor pollination quality, whereby pollinator efficiency, rather than just abundance, can play a broader role than previously appreciated. 相似文献
136.
There is growing awareness in Europe of the importance of ponds, and increasing understanding of the contribution they make
to aquatic biodiversity and catchment functions. Collectively, they support considerably more species, and specifically more
scarce species, than other freshwater waterbody types. Ponds create links (or stepping stones) between existing aquatic habitats,
but also provide ecosystem services such as nutrient interception, hydrological regulation, etc. In addition, ponds are powerful
model systems for studies in ecology, evolutionary biology and conservation biology, and can be used as sentinel systems in
the monitoring of global change. Ponds have begun to receive greater protection, particularly in the Mediterranean regions
of Europe, as a result of the identification of Mediterranean temporary ponds as a priority in the EU Habitats Directive.
Despite this, they remain excluded from the provisions of the Water Framework Directive, even though this is intended to ensure
the good status of all waters. There is now a need to strengthen, develop and coordinate existing initiatives, and to build a common framework in
order to establish a sound scientific and practical basis for pond conservation in Europe. The articles presented in this
issue are intended to explore scientific problems to be solved in order to increase the understanding and the protection of
ponds, to highlight those aspects of pond ecology that are relevant to freshwater science, and to bring out research areas
which are likely to prove fruitful for further investigation.
Guest editors: R. Céréghino, J. Biggs, B. Oertli and S. Declerck
The ecology of European ponds: defining the characteristics of a neglected freshwater habitat 相似文献
137.
生态系统服务价值的市场转化问题初探 总被引:10,自引:6,他引:4
为生态系统服务寻找建立特定的、真实的市场环境,将生态系统服务的间接价值转化为直接的经济价值,既有利于区域经济的发展,又可促进人们对生态系统服务功能的维持和保护。提出了生态系统服务价值的市场转化(率)概念,即生态系统服务价值市场转化是指为生态系统服务价值寻找建立特定的、真实的市场环境,使一些生态系统服务能够像普通商品一样进入市场流通,转化为直接的经济价值;而生态系统服务价值市场转化率(Cr)就是能够进入市场流通的服务价值(Va)占生态系统总服务价值(Vg)的比例。阐述了市场转化(率)的应用意义。在此基础上分析了全球及我国各类生态系统服务价值的市场转化情况,并提出了将来的发展思路。 相似文献
138.
The contribution of PAS 2050 to the evolution of international greenhouse gas emission standards 总被引:3,自引:0,他引:3
Graham Sinden 《The International Journal of Life Cycle Assessment》2009,14(3):195-203
Background, aim, and scope The assessment of greenhouse gas (GHG) emissions arising from products (goods and services) is emerging as a high profile
application of life cycle assessment (LCA), with an increasing desire from retailers and other supply chain organizations
to better understand, and in some cases communicate, the carbon footprint of products. Publicly Available Specification 2050:2008,
Specification for the assessment of the life cycle greenhouse gas emissions of goods and services, addresses the single-impact category of global warming to provide a standardized and simplified implementation of process
LCA methods for assessing GHG emissions from products. This paper briefly reviews the development process followed for PAS
2050, before examining the treatment of GHG-specific contribution of PAS 2050 to product carbon footprinting.
Materials and methods PAS 2050 was jointly sponsored by the Carbon Trust and the UK Department for Environment, Food and Rural Affairs and was published
by the British Standards Institution on 29 October 2008. An independent steering group oversaw the development of the specification,
including the establishment of an expert workgroup program, comprehensive international consultation, and expert input on
the requirements of the specification.
Results The development process for PAS 2050 resulted in a specification that includes specific requirements that limit the interpretation
of the underlying LCA approach to product carbon footprinting. These requirements, including goal setting and life cycle inventory
assessment, aspects of system boundary identification and temporal aspects of GHG emissions, clarify the approach to be taken
by organizations implementing product carbon footprinting, and simplify the application of LCA procedures in relation to product
carbon footprinting.
Discussion Assessment of the emissions arising from the life cycle of products has a clear international component, and delivering consistent
results across the supply chain requires the application of consistent methods. There is an emerging recognition that further
standardization of methods for product carbon footprinting is needed, and the specific requirements resulting from the PAS
2050 development process make a valuable contribution across a range of GHG assessment issues.
Conclusions The widespread interest in PAS 2050 from individuals and organizations, together with the development of similar guidance
by other organizations, confirmed that there is a need for clarification, certainty, and requirements in the field of product
carbon footprint analysis. The use of PAS 2050 to refine, clarify, and simplify existing LCA methods and standards has resulted
in specific approaches to key GHG assessment issues being developed; it is important that future standards development work
considers the impact of these approaches and their further refinement.
Recommendations and perspectives It is the consumption of goods and services by individuals around the world that drives global GHG emission, and PAS 2050
is a first attempt to provide integrated, consistent approaches that directly address the role of consumption at the product
level in contributing to GHG emissions. Climate science and GHG assessment techniques are both evolving areas and it will
be necessary to review the approach taken by PAS 2050 in the future: a formal review process for PAS 2050 will commence towards
the end of 2009 and practitioners are encouraged to participate in this review process.
相似文献
Graham SindenEmail: URL: www.carbontrust.co.uk www.ouce.ox.ac.uk |
139.
Ndola Prata 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2009,364(1532):3093-3099
It is imperative to make family planning more accessible in low resource settings. The poorest couples have the highest fertility, the lowest contraceptive use and the highest unmet need for contraception. It is also in the low resource settings where maternal and child mortality is the highest. Family planning can contribute to improvements in maternal and child health, especially in low resource settings where overall access to health services is limited. Four critical steps should be taken to increase access to family planning in resource-poor settings: (i) increase knowledge about the safety of family planning methods; (ii) ensure contraception is genuinely affordable to the poorest families; (iii) ensure supply of contraceptives by making family planning a permanent line item in healthcare system''s budgets and (iv) take immediate action to remove barriers hindering access to family planning methods. In Africa, there are more women with an unmet need for family planning than women currently using modern methods. Making family planning accessible in low resource settings will help decrease the existing inequities in achieving desired fertility at individual and country level. In addition, it could help slow population growth within a human rights framework. The United Nations Population Division projections for the year 2050 vary between a high of 10.6 and a low of 7.4 billion. Given that most of the growth is expected to come from today''s resource-poor settings, easy access to family planning could make a difference of billions in the world in 2050. 相似文献
140.
Landscape context and management effects on an important insect pest and its natural enemies in almond 总被引:1,自引:0,他引:1
Pest control mediated by organisms such as parasitoids is a valuable ecosystem service, particularly with regard to high costs, low effectiveness, and detrimental effects of some agrochemicals. This study examined infestation rates and abundance of pests and their natural enemies in organic and conventional almond orchards in California, differing in landscape context, understory plant cover, and plant species richness. Parasitoids of the commercially most important insect pest of almond, the Navel Orangeworm (NOW) were studied by rearing NOW in collected overwintering nuts. The indirect impact of vertebrate natural enemies of NOW were estimated by counting empty nut shells with feeding marks by wild birds and various mammals, found at the orchard floor. Mean nut infestation by NOW ranged from 0.8% to 37% per orchard and was reduced by parasitism rates, ranging from 0% to 22%, and vertebrate nut damage, ranging from 2% to 96% per orchard. The parasitoids were facilitated by a high proportion of natural habitat surrounding the orchards and high proportion of understory ground cover with vegetation. The vertebrate natural enemies were facilitated by a high proportion of natural habitat surrounding the orchards and plant species richness in the orchard understory. In conclusion, this study shows that pest control mediated by vertebrates and invertebrates promoted by near natural habitats can lower pest pressure by NOW larvae in overwintering almond. In case of the vertebrate nut damage this service might only be temporal and turn into a dis-service during and after harvest because the vertebrates continue to feed on the nuts and may also cause injuries to the trees. 相似文献