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101.
中国东部四个水库震例的诱震环境因素研究 总被引:1,自引:0,他引:1
本文通过对我国东部四个诱震水库的地质调查及其资料分析,探讨了水库地震诱发过程中所涉及的诸环境因素。研究表明:水库地震的诱发因素很多,但大体上可归纳成库水渗透条件和发震构造条件两类;这些环境因素只有在它们按一定方式恰当地组合成一个统一体存在于同一库区(段),水库地震才有可能诱发产生。因此,预测水库地震一个很重要的工作就是要查明库区诱发地震的环境因素及其总体组合条件。 相似文献
102.
开展干旱环境动力学研究的若干问题 总被引:18,自引:1,他引:18
根据目前干旱环境研究的现状,提出了“干旱环境动力学”的概念及其科学问题提法、研究方法论和研究途径,为干旱环境动力学的建立提供了一个科学框架。干旱环境系统是地球系统的一部分,建立干旱环境动力学,应以地球系统科学的基本原理为出发点。但它应着重研究地球系统科学中十至百年时间尺度干旱环境发展规律和趋势,特别是人类活动在该时间尺度内对干旱环境的影响。为了研究干旱环境问题,自然科学领域的地理科学、生物科学、大气科学、水文和水利以及地质学等必须形态统一的观点和普适的方法论,从而形成相对独立且学科交叉的干旱环境动力学。气候动力学已相对成熟,干旱环境动力学建模可以气候动力学为基础。建模成败的关键是如何将生态过程物理化和化学化,如何建立水文子系统、生态子系统和土壤子系统的数学模型,并与气候动力学模式相互耦合。 相似文献
103.
环境场对西北太平洋热带气旋快速增强过程的影响 总被引:5,自引:5,他引:0
利用美国联合台风预警中心整编的西北太平洋1970—2012年热带气旋(TC)最佳路径数据集及ERA-Interim再分析资料,利用极端天气法确定TC快速增强(RI)的阈值为30 kn,分析了快速增强(RI)TC的时空分布特征;从RI的样本中选取9个个例,采用动态合成分析法,对TCRI过程的环境场进行比分析。研究表明:(1)菲律宾群岛以东(10~15°N,130°E)海域为RI发生频数最多的区域,南海地区发生RI的情况明显偏少。(2)RI在1972年发生的概率最大,而在2005年发生的概率最小,1997年后,RI发生的概率波动性较大。(3)西风与西南风水汽输送结合150h Pa附近的反气旋强辐散作用,有利于TCRI过程的进行。(4)RI发生前24 h至RI发生后的6 h,TC中心附近区域平均东风切变较快增大,其值由0.5 m·s~(-1)增加到2.5 m·s~(-1)左右,之后保持在2.0~3.0 m·s~(-1),使TC处于一个有利于其RI过程的纬向风切变环境。 相似文献
104.
Trade intervention: Not a silver bullet to address environmental externalities in global aquaculture
《Marine Policy》2016
Aquaculture has been the world’s fastest growing food production technology in recent decades, and continued growth in aquaculture production is predicted. While creating economic opportunity, aquaculture is also a new way of using eco-systems, and there is substantial evidence that aquaculture creates negative environmental externalities. Although the most effective way to address these externalities may be improved governance, this approach is often difficult because most aquaculture production takes place in developing countries with limited management capacity. The fact that a large part of aquaculture production is traded motivates substantial interest in the use of trade measures to reduce environmental impacts. However, the wide variety of species, production practices, and governance systems present in aquaculture makes it unlikely that general trade measures will achieve environmental objectives. Rather, there is a real risk that trade measures will reduce economic opportunity, raise new equity concerns, and impinge on public health with little or no environmental impact. 相似文献
105.
Andrea Wulf 《Geographical review》2017,107(4):593-607
George Perkins Marsh's book Man and Nature was the first work of natural history to fundamentally influence American politics. This paper establishes the powerful impact that Alexander von Humboldt's writings had on Marsh. Marsh took ideas that Humboldt introduced across his books and synthesized them into a single powerful argument regarding the dangers of deforestation. These warnings eventually led to policies that sought to more carefully manage forestland, plant trees, and spawn the 20th century conservation movement. 相似文献
106.
基于实测资料和已有的理论结果,我们首先讨论了不同季节长江淡水的路径,还涉及了长江冲淡水对生态环境,特别对生物赖以生存的有机盐分布的影响。 相似文献
107.
Climate change adaptation, which has previously been seen as a national and local matter, is today systematically addressed by international institutions such as the UNFCCC, the FAO and the WTO. Research has focused on the overarching institutional architecture of global adaptation, particularly how it relates to development, political economy, efficiency and equity. In contrast to the transnational dimension of climate mitigation, the transnationalization of adaptation governance has received scant attention. By creating a dataset of adaptation projects, we examine transnational adaptation governance in terms of its scope, institutionalization and main functions. We find transnational adaptation governance to be firmly anchored within the UNFCCC, but a recent change towards adaptation governed by a transnational constituency can be identified. When non-state actors become integral to the project of governing adaptation, a ‘fourth era’ of adaption seems to be emerging. This new era is not replacing other forms of governing, but is emerging alongside and in a complementary fashion. In the ‘fourth era’, adaptation is increasingly governed globally and transnationally, and the attention is turned toward ‘softer’ forms of governance such as agenda setting, information sharing and capacity building. 相似文献
108.
Conservation actions generally benefit some groups more than others, and this inequity is thought to affect the probability of achieving conservation objectives. This has led to the common assumption that triple bottom line solutions – those that are effective, efficient, and equitable – are best and most likely to achieve each individual objective. Although this may be true, it has been little tested, and importantly lacks a conceptual foundation for understanding, predicting and evaluating how equity affects conservation outcomes. We describe types of equity relevant to conservation and explore how they may affect the probability of successfully achieving conservation outcomes. Depending on the equity type and context, the relationship between equity and conservation success varies. We find that the best conservation outcome is often achieved without perfect equity; highlighting the risk of ignoring the relationship between equity and success. We offer a conceptual foundation for better addressing this important issue in future research and application. 相似文献
109.
《地学前缘(英文版)》2023,14(2):101518
Lake Chany is the largest endorheic lake in Siberia whose catchment is entirely on the territory of Russia. Its geographical location on the climate-sensitive boundary of wet and dry landscapes provides an opportunity to gain more knowledge about environmental changes in the West Siberian interior during the Holocene and about the evolution of the lake itself. Sediment cores obtained from the Yarkov sub-basin of the lake in 2008 have been comprehensively studied by a number of approaches including sedimentology and AMS dating, pollen, diatom and chironomid analyses (with statistical interpretation of the results), mineralogy of authigenic minerals and geochemistry of plant lipids (biomarker analysis.). Synthesis of new results presented here and published data provides a good justification for our hypothesis that Lake Chany is very young, no older than 3.6 ka BP. Before that, between 9 and 3.6 ka BP, the Chany basin was a swampy landscape with a very low sedimentation rate; it could not be identified as a water body. In the early lake phase, between 3.6 and 1.5 ka BP, the lake was shallow, 1.2–3.5 m in depth, and it rose to its modern size, up to 6.5 m in depth, during the last millennium. Our data reveal important changes in the understanding of the history of this large endorheic lake, as before it was envisioned as a large lake with significant changes in water level since ca. 14 ka BP. In addition to hydrology, our proxies provide updates and details of the regional vegetation and climate change since ca. 4 ka BP in the West-Siberian forest-steppe and steppe. As evolution of the Chany basin is dependent on hydroclimatic changes in a large region of southern West Siberia, we compare lake-level change and climate-change proxies from the other recently and most comprehensively studied lakes of the region. 相似文献
110.
宇宙成因核素10Be示踪古地磁场的研究在海洋和冰芯研究中得到了广泛应用,然而受黄土来源及沉降过程的复杂性制约,运用中国黄土10Be示踪古地磁场变化的研究直到近年来才取得突破进展.综述了黄土10Be的研究现状并指出将其应用于地磁场示踪研究存在的关键问题,重点介绍了为分离黄土10Be浓度记录所包含的气候因素和地磁场影响因素而建立的LGM分离方法、剩磁矫顽力估算模型方法和"平均值概念"方法.各种创新数理方法的建立基本解决了黄土10Be示踪古地磁场的科学难题,使黄土10Be示踪古地磁场变化研究成为可能. 相似文献