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921.
Niels Fold  Katherine V. Gough   《Geoforum》2008,39(5):1687-1697
This paper explores the impact that a new type of pineapple, and subsequent changing consumer preferences in the Global North, has had on the livelihoods of pineapple growers in Ghana. The paper starts by tracing how research and development in Costa Rica by the world’s largest producers of pineapple, Del Monte and Dole, have resulted in a new variety MD2. This new pineapple type has been marketed in the EU through campaigns carried out by plantation companies via supermarkets. Consumer preferences have subsequently switched to MD2 away from the varieties which previously dominated the market, including the Ghanaian grown Smooth Cayenne. Ghanaian smallholders have experienced a dramatic drop in the demand for Smooth Cayenne and are unable to switch to growing MD2. The Ghanaian pineapple sector is consequently being restructured with large-scale pineapple farms, principally run by transnational companies, growing large quantities of MD2 for export. Through a detailed empirical study of the changing livelihoods of pineapple growers in two settlements in Ghana, we show how smallholders have been affected in differing ways as transnational companies have increasingly entered the market. Recent attempts to incorporate smallholders as producers of niche pineapple products are discussed. The paper illustrates the mutual benefits of linking global value chain analysis with livelihood analysis.  相似文献   
922.
殷达伟 《四川测绘》2008,31(6):256-259
本文试图寻找一种常规GPS RTK在使用上的新方法,用以解决常规GPS RTK的缺陷。GPS RTK虚拟基准站就是一种在实践中摸索出来的新方法,文中讲述了该方法的理论基础以及野外采集的要求,内业转换的办法,最后对该方法在使用范围及条件上提出了建议。  相似文献   
923.
与传统的无线电探空、雷达探测等手段相比,GNSS掩星技术为大气探测提供了一个强有力的工具,其具有无校准、全天候、精度高、垂直分辨率高、全球均匀覆盖等特点。介绍了利用GNSS掩星技术获取地球大气温、压、湿等相关参数大小的研究现状。同时,提出了GNSS掩星技术在气候研究领域的发展方向,将拓宽GNSS掩星技术在全球气候变化研究中的应用。  相似文献   
924.
A 2-year (October 2003–October 2005) high-resolution sediment trap study was conducted in Sacrower See, a dimictic hardwater lake in northeastern Germany. Geochemical and diatom data from sediment trap samples were compared with a broad range of limnological and meteorological parameters to quantify the impact of single parameters on biochemical calcite precipitation and organic matter production. Our goals were to disentangle how carbonaceous varves and their sublaminae form during the annual cycle to better understand the palaeorecords and to detect influences of dissolution, resuspension as well as of global radiation and stratification on lake internal particle formation. Total particle fluxes in both investigated years were highest during spring and summer. Sedimentation was dominated by autochthonous organic matter and biochemically precipitated calcite. Main calcite precipitation occurred between April and July and was preceded and followed by smaller flux peaks caused by resuspension during winter and blooms of the calcified green algae Phacotus lenticularis during summer. In some of the trap intervals during summer up to 100% of the precipitated calcite was dissolved in the hypolimnion. High primary production due to stable insolation conditions in epilimnic waters began with stratification of the water column. Start and development of stratification is closely related to air and water surface temperatures. It is assumed that global radiation influences the onset and stability of water column stratification and thereby determining the intensity of primary production and consequently of timing and amount of calcite precipitation which is triggered by phytoplanktonic CO2 consumption. Sediment fluxes of organic matter and calcite are also related to the winter NAO-Index. Therefore these fluxes will be used as a proxy for ongoing reconstruction of Holocene climate conditions.  相似文献   
925.
Marisa Beck 《Climate Policy》2018,18(7):928-941
Narrative research is in vogue in the social sciences. A current debate in philosophy of economics concerns the role of storytelling in economic modelling, and a growing research programme in policy studies investigates the influence of stories on policy outcomes. These two streams of research have yet to be connected in an investigation of how scientific models, in addition to delivering numerical results, also shape policy through the stories that are told with them. This article addresses that gap, arguing that stories produced with integrated assessment models of global climate change are particular types of policy narratives. An analytical framework for studying their composition and content is suggested. The narrative analysis of modelled stories illuminates some of the models' underpinning values and beliefs. These values and beliefs influence the normative, policy-relevant conclusions generated with the models. For illustration, the framework is applied to the analysis of two variations of the Dynamic Integrated Climate Economy model that are used to tell different stories about climate justice and climate policy.

Key policy insights

  • IAMs consist of mathematical structures and the stories told by manipulating these structures.

  • There is an intricate but not fully deterministic relationship between IAM structures and stories.

  • Examining both these elements contributes to our understanding of the models' role in climate governance.

  • Appreciation of modelled stories may facilitate more effective use of IAMs in the policy process.

  相似文献   
926.
At COP21 in Paris, governments reiterated the importance of ‘non-Party’ contributions, placing big bets that the efforts of cities, regions, investors, companies, and other social groups will help keep average global warming limited to well under 2°C. However, there is little systematic knowledge concerning the performance of non-state and subnational efforts. We established a database of 52 climate actions launched at the 2014 UN Climate Summit in New York to assess output performance – that is, the production of relevant outputs – to understand whether they are likely to deliver social and environmental impacts. Moreover, we assess to which extent climate actions are implemented across developed and developing countries. We find that climate actions are starting to deliver, and output performance after one year is higher than one might expect from previous experiences with similar actions. However, differences exist between action areas: resilience actions have yet to produce specific outputs, whereas energy and industry actions perform above average. Furthermore, imbalances between developing and developed countries persist. While many actions target low-income and lower-middle-income economies, the implementation gap in these countries remains greater. More efforts are necessary to mobilize and implement actions that benefit the world’s most vulnerable people.

Policy relevance

Climate actions by non-state and subnational actors are an important complement to the multilateral climate regime and the associated contributions made by national governments. Although such actions hold much potential, we still know very little about how they could deliver in practice. This article addresses this knowledge gap, by showing how 52 climate actions announced at the UN Climate Summit in 2014 have performed thus far. Based on our analysis, we argue that the post-Paris action agenda for non-state and subnational climate action should (1) find more effective ways to incentivize private sector actors to engage in transnational climate governance through actions that seek to reduce greenhouse gas emissions and promote climate resilience in a tangible manner; (2) identify factors underlying effectiveness, to take appropriate measures to support underperforming climate actions; and (3) address the large implementation gap of climate actions in developing countries.  相似文献   

927.
应用CGDPA评估中国大陆地区IMERG的降水估计精度   总被引:1,自引:0,他引:1       下载免费PDF全文
应用国家气象信息中心基于地面雨量计的逐日降水分析产品CGDPA (China Gauge-Based Daily Precipitation Analysis)为基准数据,采用定量和分类评分指标分析了2014年9月—2015年8月中国大陆地区全球降水观测GPM (Global Precipitation M easurement)多星集成降水产品IM ERG (Integrated M ulti-satellite Retrievals for GPM)的精度。结果表明:1) IMERG日平均降水量能够较好地反映我国降水量的空间分布特点(局部地区偏低),季节平均降水强度的空间分布与CGDPA具有较好的一致性(尤其中东部和南部)。2) IMERG与CGDPA日平均降水量的相关系数在大部分地区介于0. 2~0. 5,只有少数地区超过0. 6,局部地区甚至出现负相关。3) IM ERG在中国大陆东部的降水估计精度明显优于西部,但东部绝大部分地区IMERG日降水量比CGDPA偏低10%~30%,甚至更低。4) IMERG与CGDPA降水概率密度相差最大的是微量降雨,其次是中雨,其他降水强度则相差很小。5)各季节IMERG探测降水的准确率POD都比较低,空报率FAR则比较高,临界成功指数CSI也比较低。  相似文献   
928.
周雯婷  刘云刚  吴寅姗 《地理研究》2018,37(11):2288-2304
以深港边境中英街地区为例,运用实地调查和访谈方法,探讨一国两制下的深港边境生活空间形成、居民自下而上的再边界化、以及居民通过日常生活实践对边界的再定义过程。研究指出,中英街地区的生活空间形成是在边界效应下,边境居民对边境两侧管理差异的不断适应、调试、乃至主动运用的空间构建过程。边境管理者、居民、游客和水客等多方力量在此过程中互动角力,而中英街地区发展的不同阶段正是这一互动过程的结果;在此过程中,边境居民从被动的边界适应到主动的边界效应利用,体现了一国两制下居民的生活空间战略和自下而上的社会力量对边界及边境地区生活空间形成的作用。本研究有助于深化对于亚洲的边界和边境地区空间形成的理解,也对当下的边境治理具有积极的政策意义。  相似文献   
929.
彭华  何瑞翔  翁时秀 《地理研究》2018,37(12):2383-2398
在乡村振兴战略背景下,乡村旅游地的城镇化研究亟需总结更多更好的中国经验。福建省泰宁县水际村1991-2016年的旅游城镇化体现了一种学界尚未关注到的多主体共治模式,村民在保持地权关系不变的情况下,通过多主体的良性互动实现了就地城镇化。在城镇化过程中,得益于政府的引导、培育和制度建设,乡村经济在利益冲突中保持韧性并持续发展;外来企业的进入则带动了村民经济收入的增长,村民在商业运营中完成了生活方式现代化和思维观念市民化。本文按照案例研究的逻辑,分析了多主体共治状态的形成过程、核心要素及其作用机制。多类主体实现共治的核心要素是有效的制度供给、合理的科层制分工、灵活的产权设计、实现分配正义的市场规则和多类主体之间的理性互动与权力制衡。基于这些核心要素的共同作用,多类主体之间实现共同利益最大化,保障资源效益可以有效地进行再分配,最大限度地发挥旅游促进乡村经济发展和改善人民生活的城镇化目标。可以认为,多主体共同治理是实现乡村旅游城镇化的有效途径。总结这种模式有利于丰富新型城镇化的乡村个案,同时为新时期乡村转型的有效治理提供参考。  相似文献   
930.
对机构改革背景下空间规划体系构建的思考   总被引:1,自引:1,他引:0  
郝庆 《地理研究》2018,37(10):1938-1946
“建立空间规划体系”是自然资源部的一项重要职能,也是整合空间规划、保障空间治理机制有效运行的必然要求。在借鉴国外空间规划体系的基础上,按照适应中国政治体制和法律基础、适应未来空间开发和空间治理变化的需求,提出构建层层传导的空间规划体系确保国家重大战略部署得以落实;提出在微观尺度空间规划进行空间开发权与土地利用权的分配,作为实施空间用途管制的法律依据,保障地方多样化、灵活化的发展;通过构建“宏观政策性/指导性规划—中观衔接性规划—微观实施性规划”的空间规划体系,为国家建立和完善空间规划体系、提升空间治理能力提供参考。  相似文献   
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