全文获取类型
收费全文 | 1304篇 |
免费 | 48篇 |
国内免费 | 33篇 |
专业分类
测绘学 | 33篇 |
大气科学 | 348篇 |
地球物理 | 52篇 |
地质学 | 219篇 |
海洋学 | 134篇 |
天文学 | 3篇 |
综合类 | 75篇 |
自然地理 | 521篇 |
出版年
2024年 | 3篇 |
2023年 | 6篇 |
2022年 | 32篇 |
2021年 | 31篇 |
2020年 | 35篇 |
2019年 | 58篇 |
2018年 | 61篇 |
2017年 | 63篇 |
2016年 | 66篇 |
2015年 | 55篇 |
2014年 | 47篇 |
2013年 | 239篇 |
2012年 | 40篇 |
2011年 | 52篇 |
2010年 | 49篇 |
2009年 | 49篇 |
2008年 | 55篇 |
2007年 | 64篇 |
2006年 | 46篇 |
2005年 | 45篇 |
2004年 | 34篇 |
2003年 | 37篇 |
2002年 | 27篇 |
2001年 | 27篇 |
2000年 | 33篇 |
1999年 | 31篇 |
1998年 | 23篇 |
1997年 | 14篇 |
1996年 | 5篇 |
1995年 | 8篇 |
1994年 | 4篇 |
1993年 | 6篇 |
1992年 | 2篇 |
1991年 | 7篇 |
1989年 | 1篇 |
1988年 | 7篇 |
1987年 | 4篇 |
1986年 | 3篇 |
1985年 | 5篇 |
1984年 | 4篇 |
1983年 | 4篇 |
1982年 | 1篇 |
1980年 | 1篇 |
1978年 | 1篇 |
排序方式: 共有1385条查询结果,搜索用时 15 毫秒
101.
Introduction Earthquake often brings large catastrophe to the mankind, especially in recent years when a large number of destructive earthquakes occur in the whole globe, which have caused tremendous casualties and losses to the people. Obviously, it is not very reasonable to make up financial losses and carry out post-seismic reconstruction by the government only for such kind of huge earth- quake losses. Therefore, as an effective measure to raise fund and make up financial losses, earth- qu… 相似文献
102.
Geoff Kelly 《Geoforum》2007,38(2):326-338
The development of renewable energy sources is of prime interest to many countries seeking to pursue greenhouse gas emission reduction obligations. The increased use of renewables offers the possibility of not only contributing to emission reduction, but at the same time improving energy supply diversity and security, and developing employment and business in related supply industries. Two main mechanisms are in common use, one a quota (quantity) instrument often associated with tradable certificates, and the other a prescribed pricing mechanism. This paper considers the renewable energy development strategies of three countries (the UK, Australia, and New Zealand) all using a variant of the quota/certificate approach as the central instrument in their programs. The regulatory frameworks defining the application of the certificate systems differ notably, and the likely differing outcomes suggest that these regulatory settings may be at least as important as the selection of the basic policy instrument, in determining the overall success of programs of this nature. 相似文献
103.
Terry van Dijk 《Geoforum》2007,38(3):505-511
An integral part of post-socialist transformation under the Washington Consensus has been the privatisation of previously state owned and/or co-operative farms. In many instances, there have been attempts at ‘turning back the clock’ to pre-War conditions, including land ownership structures. Frequently, the result has been the division of large, economically efficient units into numerous, small and economically barely viable private plots. Following accession to the European Union, these re-constituted peasant-scale structures pose a major challenge to the Union’s agricultural policy. As this paper demonstrates, a simple transfer of western European practices, such as land consolidation, is not possible. The particular legacies of the communist system have given land ownership particular values, legitimacy and personal identity, and emotional bonds. Simple technocratic solutions, as applied in the West earlier, are thus not feasible. Consequently, the paper points out, new forms and instruments of tackling disadvantageous agricultural structures need to be found. 相似文献
104.
Through their consumption behavior, households are responsible for 72% of global greenhouse gas emissions. Thus, they are key actors in reaching the 1.5 °C goal under the Paris Agreement. However, the possible contribution and position of households in climate policies is neither well understood, nor do households receive sufficiently high priority in current climate policy strategies. This paper investigates how behavioral change can achieve a substantial reduction in greenhouse gas emissions in European high-income countries. It uses theoretical thinking and some core results from the HOPE research project, which investigated household preferences for reducing emissions in four European cities in France, Germany, Norway and Sweden. The paper makes five major points: First, car and plane mobility, meat and dairy consumption, as well as heating are the most dominant components of household footprints. Second, household living situations (demographics, size of home) greatly influence the household potential to reduce their footprint, even more than country or city location. Third, household decisions can be sequential and temporally dynamic, shifting through different phases such as childhood, adulthood, and illness. Fourth, short term voluntary efforts will not be sufficient by themselves to reach the drastic reductions needed to achieve the 1.5 °C goal; instead, households need a regulatory framework supporting their behavioral changes. Fifth, there is a mismatch between the roles and responsibilities conveyed by current climate policies and household perceptions of responsibility. We then conclude with further recommendations for research and policy. 相似文献
105.
南宁大地建筑装饰工程公司,由一个小的、效益欠佳的企业发展成为一个初具规模的中型企业,是由于强化了管理这个中心环节。实践证明,队伍的管理、质量的管理是企业发展的两个关健因素,,再加上领导者的正确决策,对各种因素的综合利用和协调艺术,就能为企业的发展提供保证。 相似文献
106.
JOHN OPIE 《Geographical review》1998,88(2):241-258
ABSTRACT. When American society, through deliberate government action, intervenes to preserve the family farm as the locus of “good” human values and “authentic” environmental conditions, the result can be described as a moral geography. Nowhere is this clearer than in the protection of traditional farming on the High, or Great, Plains through federal funding and programs. Protection began during the Dust Bowl of the 1930s; federal support came to a close with the passage of the 1996 farm bill. These shifts deserve assessment of historic American interests in the protection of an agricultural institution and of a region at risk. 相似文献
107.
现代以色列经济是外向型经济。90年代以来,中东和平进程在前进,以色列经济在发展,工党政府和利库德集团政府都把进一步改革开放、奠定以色列的中东经济强国地位作为主要目标,为此,制定了推进私有化、吸引外资、扩大对外贸易的政策以及一系列相关政策,对以色列经济的现状和将来有着重大影响,也对中东区域经济的发展有着促进作用,同时也存在着某些问题。 相似文献
108.
Jacques Lévy 《GeoJournal》1998,46(4):279-283
The paper initially describes some of the most important historical processes that have conditioned France's geopolitical position in the contemporary world. It discusses the current changes in France's geopolitics as a changing reality of international relations and as a changing discourse of scholars and experts, that reflects those real world changes. The paper focuses on French politics in Africa and on France's policy in Europe after the end of the Cold War. In Africa the French post-colonial empire with its close ties between domestic regimes, French business interests and the French state becomes unsustainable after the bipolar rivalry has been suspended. In Europe French policy can no longer be presented as either an independent view among a series of others (Europe des patries) nor as a successful effort to press French views by way of a larger European entity. The paper presents an overview of geopolitical literature written in France as a reflection of these conditions. 相似文献
109.
黄河下游引黄灌区水价与水资源调控* 总被引:3,自引:1,他引:2
40多年来,我国水利建设取得了巨大成就,但是,在以往的计划经济条件下,水利事业普遍存在着“重建轻管”的问题,延续至今,尚未妥善解决,从而导致一些地区水资源的极度浪费及出现不良的环境后效。水资源管理是水资源合理开发利用的基本保证,它涉及到政策、法律、体制、经济及现代科学技术,是一个跨部门、跨学科的系统工程。目前,我国在水资源管理中最突出的问题是尚未完全纳入市场经济的轨道,水价远低于供水成本,不能发挥水费征收的经济杠杆作用,遏制水资源的浪费及合理地调控地表水与地下水资源,同时,偏低的水价也使供水部门缺乏足够的资金进行工程运营与维修,造成工程老化,降低供水效率[1].黄河下游灌区,位于豫鲁两省境内,灌溉面积约2800万亩(186.6×104hm2),多年平均引水量在100×108m3左右,该灌区自50年代末引黄灌溉以来,上述问题表现尤为突出。随着黄河上、中游地区的发展,用水量增加,使黄河下游灌区的用水矛盾越来越突出。此文试图以此为典型,分析供水成本的构成、现行水价确定中存在的问题及其对水资源调控的影响,供水价问题的深入研究及水价政策的制定参考。 相似文献
110.
发展城市地质科技 构筑地质人才高地 总被引:2,自引:0,他引:2
上要建设成现代化国际大都市,城市地质工作必须确保上海城市建设各项规划任务的顺利实现。通过总结经验,转变观念,及时把握机遇,发展城市地质科技,构筑地质人才高地,为新世纪上海城市建设大发展作出新的贡献。 相似文献