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101.
Particulate samples were collected from the Changjiang river system during a flood period, in May 1997, and POC, stable isotope and lipids associated with particles were examined. Results showed the decrease (0.84% ~ 1.88%) of organic carbon content from the upper reaches to the estuary.δ13C values of particulate organic carbon was in the range of -24.9×10-3 to -26.6×10-3, which were close to the isotopic signature of continental C3 vegetation. Total particulate n-alkanes concentrations varied from 1.4 to 10.1μg/dm3,or from 23.7 to 107μg/g of total suspended matter. Fatty acids were present in all the samples, from 1.4 to 5.4μg/dm3, with saturated and unsaturated straight-chain and branched compounds in the carbon number range from C12 to C30. Both δ13C and the ratio of carbon content to nitrogen content indicate the predominance of terrestrial inputs (soil organic matter) among the particles. The biomarker approach has been used to identify the relative portion of terrigenous and autochthonous fraction in the particulate samples. The distribution of fatty acids suggests a striking phytoplanktonic and microbial signal in most particle samples. The terrestrial alkanes are used to estimate the contribution of terrestrial inputs along the mainstream. 相似文献
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103.
Patrick D. Nunn 《Singapore journal of tropical geography》2013,34(2):143-171
As in the past, most Pacific Island people live today along island coasts and subsist largely on foods available both onshore and offshore. On at least two occasions in the 3500 years that Pacific Islands have been settled, sea level changes affected coastal bioproductivity to the extent that island societies were transformed in consequence. Over the past 200 years, sea level has been rising along most Pacific Island coasts causing loss of productive land through direct inundation (flooding), shoreline erosion and groundwater salinization. Responses have been largely uninformed, many unsuccessful. By the year 2100, sea level may be 1.2 m higher than today. Together with other climate‐linked changes and unsustainable human pressures on coastal zones, this will pose huge challenges for livelihoods. There is an urgent need for effective and sustainable adaptation of livelihoods to prepare for future sea level rise in the Pacific Islands region. There are also lessons to be learned from past failures, including the need for adaptive solutions that are environmentally and culturally appropriate, and those which appropriate decision makers are empowered to design and implement. Around the middle of the twenty‐first century, traditional coastal livelihoods are likely to be difficult to sustain, so people in the region will need alternative food production systems. Within the next 20–30 years, it is likely that many coastal settlements will need to be relocated, partly or wholly. There are advantages in anticipating these needs and planning for them sooner rather than later. In many ways, the historical and modern Pacific will end within the next few decades. There will be fundamental irreversible changes in island geography, settlement patterns, subsistence systems, societies and economic development, forced by sea level rise and other factors. 相似文献
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105.
水资源约束条件下的干旱区产业结构态势分析--以黑河流域中游地区为例 总被引:4,自引:0,他引:4
文章简要介绍了黑河中游地区水资源概况,分析了该地区现状用水结构及其存在的问题,指出水资源的可持续利用不仅要通过农业节水来完成,特别是在当前情况下,积极实现用水结构的调整,将宝贵的水资源分配到更有经济效益的产业,以实现水资源的合理配置和高效利用,构建节水型社会,是中游地区产业结构重点调整的方向。并就此提出了今后中游地区基于水资源条件的区域可持续发展的产业结构模式。 相似文献
106.
This paper argues, following Friedrich Nietzsche, that recent evaluations of Google Earth uncritically privilege the product’s Apollonian determinations at the expense of its Dionysian uncertainties. Specifically, when we understand Google Earth as a virtual globe composed of surveyed panoramas, sober rationalization, dystopic control, and transparent order – or, even, as a tool for participation and empowerment – we undersell its capacities as an alluring digital peep-box, an uncertain orb spangled with vertiginous paranoia, frenzied navigation, jubilatory dissolution, and intoxicating giddiness. We argue that the former interpretations not only risk foreclosing our theorizations about how Google Earth is actually used in various ways and different contexts, they also reproduce a one-dimensional and conservative reading of technology that can be traced back (at least) to the writings of Theodor Adorno. By drawing on the work of Walter Benjamin (Adorno’s critic and pen pal for more than a decade) we aim to ‘go beyond Apollo and Adorno’ by illustrating the extent to which Apollonian order and Dionysian love makes Google Earth go round. To do this, we examine Google Earth as a “digital peep-box” with an online collective that revels in its “Spot the Black Helicopter” competitions; illuminated profanities; alien and giant insect invaders; naked sunbathers; and crashed transport planes in Darfur. 相似文献
107.
陈青松 《广东海洋大学学报》2004,24(2):8-12
人的精神生活是人之为人的一种特定方式,提升人的精神生活是全面建设小康社会的重要内容.在全面建设小康社会的过程中,我们要依靠加强思想道德建设、大力发展教育科学文化事业和在全社会深入开展和普及法制教育等手段来建设人的精神生活. 相似文献
108.
汪树民 《广东海洋大学学报》2006,26(5):20-23
促进社会和谐既是我国发展的重要目标和必要条件,又是我党执政能力的具体体现。当前我国社会诸多不和谐因素的存在,对于执政的中国共产党来说既是挑战也是机遇。和谐社会的创建,客观上要求提高中国共产党的执政能力,而提高党的执政能力又是实现我国社会和谐的重要条件和根本政治保障。执政能力的高低要靠执政实践来检验。所以,能否建成和谐社会,直接关系到中国共产党执政的成败。和谐社会的建设不是一蹴而就的,这将是一个长期的过程,中国共产党执政能力和执政水平的提高也将是一个渐进的过程。 相似文献
109.
Paul Claval 《GeoJournal》2000,51(1-2):73-81
Capital cities reflect the nature and organization of the states they control. Their functional role is higher in centralized systems, societies where the state is the source of all legitimacy, and countries using Continental Law. It is lower in federal systems, pillarized societies and countries, which are ruled according to a Common Law. The symbolic status of capital cities is higher when the state is the source of all legitimacy, lower in consociationalist societies. Theses processes were responsible for the development of two types of political capital cities and one type of economic and cultural capital cities during the nineteenth century. A partial standardization of the functions and statuses of capital cities occurred later. The European Union is neither a state nor a super-state since its main responsibilities are still in the economic field, it lacks a huge administrative bureaucracy and does not have definitive territorial limits. The European Union has officially three capital cities, Strasbourg, Luxembourg and Brussels. The really important one is Brussels. Its functions are nevertheless quite different from those of national capital cities during the first half of the twentieth century. European capital cities are thriving because most of them managed to become economic metropolises. The result is that the European Union has a complex and rapidly evolving system of capital cities. 相似文献
110.
YI‐FU TUAN 《Geographical review》2002,92(3):307-318
ABSTRACT. “Community” is a good warm word frequently invoked by citizens, social workers, and politicians. “Society,” by contrast, is more ambivalent, invoking something elitist and exclusive, as in the expression “high society.” The word “individual,” or “individualism,” often connoting selfishness and bracketed with society, is even more suspect in our time. I plead for a restoration of balance and esteem among the three terms as a necessary step toward acquiring a fuller understanding of the human condition and potential. 相似文献