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931.
932.
933.
海岸带是陆海相互作用强烈的特殊界面,其空间利用的负外部性具有典型的跨区域特征,需要以全局性、整体性、系统性的思维实施用途管制。本文引入区际负外部性理论,将研究对象从空间和空间利用转到伴随空间利用所产生的人地(海)关系的演变过程。首先,梳理海岸带空间利用区际负外部性的几种典型表现形式,进而构建海岸带区域系统,并明确了系统间的作用关系;其次,从区域系统作用的视角阐述海岸带空间用途管制的作用机制和具体手段;最后,提出政策建议,以期为海岸带空间用途管制的制度完善提供理论支撑和决策支持。 相似文献
934.
基于GIS广州市主城区地面塌陷危险性评价 总被引:1,自引:0,他引:1
地面塌陷是珠江三角洲城市地质灾害的主要类型之一。广州市主城区地面塌陷频繁发生且损失严重。采用信息量数学模型与GIS技术结合对其地面塌陷灾害进行危险性评价。选取了断裂构造、地壳稳定性、第四系覆盖层厚度、基岩岩性、地下水动力条件、地表人类活动强度和地下活动强度等7个指标中的21个变量构建了危险性评价指标体系,应用ArcGIS软件参与了数据的采集、管理、分析和评价结果表达等过程,将广州市地面塌陷灾害危险性分为极不稳定级、不稳定级、次不稳定级、基本稳定级和稳定级5个等级,极不稳定级主要分布在主城区西北角,次不稳定级分布面积最广。研究结果表明:复杂的地质环境和剧烈的人类活动相耦合,加剧了地面塌陷的发生。 相似文献
935.
IINTRODUCTIONLanduse/coverisoneofthemostimportalfactorseffectingsoilandwaterloss.Researchonlanduse/coverandwaterandsoillosswithremotesensinghasbeendonemuchinthepast.Butremotelysensedimageryonlycarriestheinstantaneousandtwo-dimensionalinformationofitsprototypegeographicobjects(ChenandZhao,1990).Thereforemathematicalandphysicalprocessingonremotelysensedimageoftenproduceindefiniteandunreliableresult.Inordertoimprovetheprecisionofclassification,otherdatasetssuchastopographicmaps,thematicmaps… 相似文献
936.
数字遥感技术在土地利用动态监测中的应用概述 总被引:36,自引:1,他引:35
对数字遥感技术在土地利用动态监测中的应用进行了简单的论述,介绍了土地利用动态遥感监测的概念、方法、过程以及监测中存在的难点,如数据预处理、监测方法的选择等。强调了今后应加强数字遥感技术在资源和环境管理中的应用研究。 相似文献
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938.
SARAH LUMLEY 《The Australian geographer》1999,30(1):35-49
Many of the controversies about environmental resource use relate to the perceived conflict between economics and conservation. This conflict might have been resolved with general acceptance of the concept of sustainable development, and with a more transparent and honest use of economics terminology. However, interpretation and application of this concept appear to have led to some further conflicts between perceptions of economics and the environment, partly because commerce and development are sometimes portrayed as having the same meaning. Commercial activity resulting from the use of natural resources is often held to promote social good, while conservation of natural resources, many argue, renders the wealth which may be obtained from such resources unavailable. The latter is deemed to be bad for society. However, although in contemporary parlance economics is usually restricted implicitly to issues concerning commerce, finance and profit, economic theory requires the consideration also of intangible values, such as environmental damage. Environmental and other economists have worked hard to stress the importance of non-financial values in economic theory, and to ensure that they are included in economic analysis. However, these latter aspects of economics are not generally known to the wider public, partly because of the tendentious manner in which interested parties often use economics. When positions are argued on the basis of economics, the arguments are frequently expressed in language designed to persuade members of the community that all commercial activity is in the interests of society, while incurring minimal costs. In these circumstances, economics might be viewed as a form of rhetoric. Anyone assessing the merits of such arguments ought to consider carefully what this rhetoric really means. This is especially important in discussions concerning sustainable development, which is understood by some to mean sustainable, or sustained, commerce. 相似文献
939.
Allan Curtis Marike Van Nouhuys Wayne Robinson Jacinta MacKay 《The Australian geographer》2000,31(3):349-366
Landcare is an important example of the potential of state-sponsored participation to establish viable local organisations and contribute to rural development. In this paper, the authors discuss their research using organisational theory to explore Landcare effectiveness. Data were obtained from a mailed survey to Landcare groups in the state of Victoria during 1998. Levels of group activity were used as a surrogate measure of group effectiveness. Groups were ranked according to their level of activity to assess the impact of factors likely to affect group performance, the efficacy of program logic, and the extent groups were contributing to program goals. Survey data suggested key aspects of Landcare Program logic were sound. Examination of the membership and activity profiles of groups suggested 90 per cent of the respondent groups were making a worthwhile contribution to program goals. This research also confirmed the importance of factors identified by others as significant influences on organisational effectiveness: the importance of having clear goals, objectives and plans; resource availability; facilitation by an outside agency; access to a funded group co-ordinator; and communication between stakeholders. Unfortunately, there are critical, ongoing management issues surrounding many of these topics. 相似文献
940.
D.J. Walmsley 《The Australian geographer》2000,31(1):5-19
It is over 30 years since the concept of community without propinquity was first proposed. According to this concept, communities might be spatially far-flung, but nevertheless close-knit, intimate and held together by shared interests and values, rather than by geographical proximity. Although the idea of community without propinquity has been heavily criticised, the advent of advanced telecommunications and the emergence of cyberspace mean that a reappraisal of the concept, and of the changing nature of community generally, is warranted. The paper undertakes such a reappraisal. A review of the literature on cyberspace reveals several reasons why the social effects of advanced telecommunications and the Internet might be less than is sometimes predicted. Setting this discussion in the context of other social science discourses on new urbanism, consumption rather than production as a basis for city life, postmodernism, and 'the third way' in politics, shows that place and local community are, and will continue to be, fundamental to the functioning of society. Cyberspace might have annihilated distance but not place. 相似文献