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111.
秦巴山区村域稳定脱贫测度及返贫防控风险识别——以重庆市城口县为例 总被引:2,自引:1,他引:1
深度贫困地区农村实现稳定脱贫、建立返贫防控机制是后2020时代的现实要求,更是精准扶贫与乡村振兴承上启下的紧密衔接。以强度生态脆弱与集中连片特困复合地区重庆市城口县为研究区域,基于脱贫稳定性测度模型、障碍度模型和最小方差模型等方法对城口县60个行政村、1950个农户进行多维脱贫稳定性空间分异特征和返贫风险模式探究。研究发现:① 样本村脱贫稳定性等级分布总体呈现前端窄小、中部突出的“葫芦状”结构,各地区多维脱贫稳定性总体不高且存在空间异质性;② 城口县返贫风险可识别为双风险模式、三风险模式、四风险模式和五风险模式4种模式及各阻力因素多元整合主导的11种返贫风险类型,人力资本、发展机会等涉及农户可持续增收、动态抗风险能力及内生动力的要素逐渐成为现阶段返贫防控及减贫路径依赖的重点;③ 立足区域特征,把继续攻坚和稳定脱贫、防止返贫摆在同等重要位置上,因村施策提高群众抗风险能力,精准织密防止脱贫群体的返贫网。 相似文献
112.
论中国人地关系演进的新时代特征——“中国人地关系研究”专辑序言 总被引:1,自引:0,他引:1
人地关系是地理学科古老又年轻的话题,其内涵伴随人类社会发展不断丰富,具体表现形式也具有鲜明的时代特性。自吴传钧先生提出人地关系地域系统理论以来,人地关系在学科建设及国家重大发展战略制定研究中发挥着基础科学支撑作用,其作为地理学研究核心的地位逐步被强化。在人地冲突不断加剧的时代背景下,深化对人地关系的系统认知,基于人地关系地域系统理论探讨人地关系动态演进的理论基础,并从综合视角审视新时期中国人地关系的演进过程、核心特征及机制,继而探讨现代人地关系的协调路径。总的来说,人地关系演进的实质是人地要素之间围绕发展空间的博弈过程,新时期中国人地关系演变速度加快,人地要素的相互作用程度不断加深。通过技术进步、增加要素投入和调配资源等方式,中国基本已化解了“以量为主”的第一代人地矛盾,而进入“以质为主”的第二代人地矛盾期。典型表现是,粮食总量不再短缺,但在生产粮食过程中引发的土壤退化和水资源污染等问题加剧;区域性资源不再短缺,但在跨区域开发调配资源过程中引发的生态退化和环境污染等问题凸显。提升人的思想认知和加深对人地关系的综合认知是纠偏人地演进路径的关键。 相似文献
113.
对条带状铁建造(BIF)进行精确的年代学约束,具有非常重要的科学意义,可以获得BIF的时间分布趋势,反映对应时代的大气和海洋环境,准确建立与重大地质事件的对应关系,为铁建造的成因提供依据。本文在综合前人资料的基础上,重新绘制了全球BIF形成时代的分布图,结果表明BIF在3.6~1.6 Ga连续分布,在2.8~2.7 Ga、 2.5~2.4 Ga、 1.9~1.8 Ga的3个区间范围内形成高峰;Algoma型BIF主要集中于中-晚太古代,而Superior型BIF主要出现在古元古代。本文重点对前人关于BIF年代学的测试方法及其应用进行了介绍和评述,结果表明目前锆石U-Pb测年法依然为主要手段,而Sm-Nd等时线法和Re-Os等时线法尽管有效,但直接测定BIF条带的Sm-Nd等时线和磁铁矿的Re-Os等时线年龄仍存在较大问题,但可用来反映物质的来源以及后期构造热事件的改造等问题,而采取BIF相关单元的年龄来间接代表BIF的形成年龄是目前较为成熟的方法,其中测定铁建造火山岩夹层锆石U-Pb年龄是国际上测定BIF时代常用的手段。 相似文献
114.
日干配错断裂位于青藏高原中部, 是"V"型共轭走滑构造中班公湖—怒江缝合带以北的一条NEE-SWW走向左行走滑断裂, 在调节青藏高原南北向挤压和东西向伸展过程中起着重要的作用.在2008年1月9日及2020年7月23日, 先后在该断裂南西端和北东支分别发生6级以上强震.因此, 查明该断裂的晚第四纪活动性及其与区域强震活... 相似文献
115.
Andrew Jordan Tim Rayner Heike Schroeder Neil Adger Kevin Anderson Alice Bows 《Climate Policy》2013,13(6):751-769
Since the mid-1990s, the aim of keeping climate change within 2?°C has become firmly entrenched in policy discourses. In the past few years, the likelihood of achieving it has been increasingly called into question. The debate around what to do with a target that seems less and less achievable is, however, only just beginning. As the UN commences a two-year review of the 2?°C target, this article moves beyond the somewhat binary debates about whether or not it should or will be met, in order to analyse more fully some of the alternative options that have been identified but not fully explored in the existing literature. For the first time, uncertainties, risks, and opportunities associated with four such options are identified and synthesized from the literature. The analysis finds that the significant risks and uncertainties associated with some options may encourage decision makers to recommit to the 2?°C target as the least unattractive course of action. 相似文献
116.
《Climate Policy》2013,13(5):516-526
This article proposes a shift to a paradigm that is more extensive than the current narrow focus on North—South climate change technology transfers, towards a more inclusive ‘global’ paradigm. An implication of the paradigm shift is that there should be a concomitant expansion of the policy agendas of the international climate and trade regimes. The traditional North—South paradigm of technology transfer ignores the increasing importance of developing countries as sources of advanced climate-friendly technologies, and therefore ignores South—North and South—South transfers. Further, whereas the North—South paradigm has emphasized developing countries' intellectual property rights policies as barriers to technology transfers, the ‘global’ paradigm focuses attention on trade and investment policy barriers, including developed countries' policies that inhibit technology transfer from developing countries. The analysis is relevant to international negotiations in the post-2012 climate regime, and is also relevant to the future development of the trade regime—not only at the multilateral level in the WTO, but also at the regional and bilateral levels. 相似文献
117.
《Climate Policy》2013,13(3):317-336
This article assesses a wide range of alternative proposals for post-2012 international climate policy regimes. We believe that these proposals will serve as a basis for debates about how to configure post-2012 climate policy. The article characterizes and assesses the policy proposals along the lines of five key policy dilemmas. We argue that (1) many proposals have ideas on how to reduce emissions, but fewer have a solution on how to stimulate technical innovation; (2) many proposals formulate climate policy in isolation, while there are fewer proposals that try to mainstream climate policies in other policy areas; (3) many proposals advocate market-based solutions, while fewer realize that there are certain drawbacks to this solution especially at the international level; (4) most proposals have a preference for a UN-based regime, while a more fragmented regime, based on regional and sectoral arrangements may be emerging; and (5) most proposals have ideas about mitigation, but not many have creative ideas on how to integrate mitigation with adaptation. 相似文献
118.
《Climate Policy》2013,13(2):207-220
Since 2005, Parties to the UNFCCC have been negotiating policy options for incentivizing reductions of (greenhouse gas) emissions from deforestation and degradation (REDD) in a future climate regime. Proposals on how to operationalize REDD range from market-based to pure fund-based approaches. Most of the current proposals suggest accounting for REDD at the national level. Accounting for emission reductions and implementing policy reform for curbing deforestation will take time and imply high levels of technical and institutional capacity. Therefore it is essential that developing countries receive sufficient support to implement national REDD programmes. To save time and ensure prompt action in reducing deforestation, a REDD approach is proposed that integrates project-level and subnational REDD schemes into national-level accounting. This ‘nested approach’ can achieve meaningful reductions in GHG emissions from improved forest governance and management, while allowing for an immediate and broad participation by developing countries, civil society and the private sector. 相似文献
119.
《Climate Policy》2013,13(6):634-651
A fair, effective, flexible and inclusive climate regime beyond 2012 will need several political balances. Mitigation and funding will be at the heart of the agreement. The IPCC's Fourth Assessment Report indicates that absolute reductions will be needed in Annex I (AI) countries and substantial deviation from baseline in some non-Annex I (NAI) regions by 2020. Although the latter was not explicitly quantified by the IPCC, the EU subsequently proposed a range for developing countries. Sharing the burden for mitigation is essentially zero-sum: if one does less, the other has to do more. We critically examine the implicit assumption that NAI countries would pick up the remainder of the required global effort minus the AI contribution. We suggest that greater levels of ambition can be achieved by turning the formula around politically, starting from the achievable ‘deviation below baseline’ given NAI's national programmes and appropriate international support. AI countries may have to exceed the IPCC ranges or pay for the remainder. For notional levels of NAI mitigation action, Annex I has to reduce by between ?52% and ?69% below 1990 by 2020, only dropping to a domestic ?35% with commitments to offset payments through the carbon market. Given the large mitigation gap, a political agreement on the question of ‘who pays’ is fundamental. The carbon market will provide some investment, but it mainly serves to reduce costs, particularly in developed countries, rather than adding to the overall effort. Market-linked levies and Annex I public funding will therefore be crucial to bridge the gap. 相似文献
120.