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121.
This paper discusses the imperatives of sand search and describes two case histories of sand search in the Niger Delta. These case histories highlight the project cycle of sand search operations and circumstances in which environmental peculiarities can influence procedures and strategies. Field and laboratory procedures emphasise the applications of particle-size distribution and compaction tests to field construction control. The need to integrate mitigative measures of potential impacts into the planning and execution of projects has been emphasised. Some environmental consequences of sand dredging have also been highlighted. 相似文献
122.
河南信阳茶叶资源环境优势及发展 总被引:4,自引:0,他引:4
信阳茶叶是河南省南部大别-桐柏山区的重要经济作物资源之一。该区域地处北亚热带,气候温暖湿润,生态环境复杂多样,植物资源丰富,是河南的鱼米之乡。气候条件独特,利于优质茶叶生长。因此,虽然以信阳毛尖为代表的信阳茶区茶叶面积小,茶叶总产量少,但产品质量上乘,深受茶叶消费者的喜爱,是全国名优绿茶重要产区。依据信阳茶区茶叶资源环境优势,提出进行名优绿色无公害茶产品的开发;组织茶叶产业化发展;加强信阳茶叶生产的标准化研究推广工作和加强对外经济技术联系协作,为河南省信阳茶叶可持续发展提供科学依据。 相似文献
123.
Landslides in Sado Island of Japan: Part I. Case studies, monitoring techniques and environmental considerations 总被引:1,自引:0,他引:1
Lulseged Ayalew Hiromitsu Yamagishi Hideaki Marui Takami Kanno 《Engineering Geology》2005,81(4):419-431
A sufficient knowledge on the kinematics and development of landslides helps to adopt proper measures that can be used to protect slopes and the environment in general. This can be achieved by adequate monitoring programs. This paper presents the findings of intensive monitoring activities carried out on Shiidomari and Katanoo landslides found in Sado Island of Japan. More than one year of observation of the two landslides allowed defining some peculiar futures of their kinematics and style of development. The problem of slope instability in the two areas is generally accredited to various factors. But, both landslides were triggered by heavy rainfalls and snowmelt. Because of the outline of the area and the presence of relict topographic features, the Shiidomari landslide is considered to be a large-scale reactivation of old slope failures. The Katanoo landslide is, however, a first-time case. Geophysical investigations and drilling activities in Shiidomari indicated the presence of two slip planes. The deepest (80–100 m) of these is controlled by existing lineaments. Monitoring data suggests that the body of the landslide has subsided as much as 1.16 m just below the main scarp, but a centimeter in the central region. The toe sector also experienced a significant amount of subsidence, but this was counter-balanced by an uplift on the opposite side of the landslide. Hence, the landslide seems not any more active along the deepest slip surface, although it may extend upward and define a series of shallow shear planes around the crown. In the case of Katanoo, the landform characteristics, differential weathering, the road cut and groundwater fluctuations appeared to contribute much to determine the exact location of the landslide. Extensional cracks that preceded the landslide can be related to heavy rainfalls and the cold and warm cycles thereafter. Subsurface investigations and monitoring works indicated that the landslide has two slide blocks with different slip planes. During the observation period, the upper part of the landslide responded more effectively to rainfall and snowmelt than the middle and lower sections. The corresponding movements, however, appeared to settle about three months after failure. There were also little strain transmissions in boreholes and no significant change in the characteristics of the landslide. The kinematics of deformation of many of the slopes in Sado Island resembles that of Shiidomari landslide. But mass movements along highways and mountain roads are usually similar to Katanoo. Landslides of the type like Shiidomari may not show sudden and drastic failures, but are usually long lasting and can reactivate repeatedly along new, shallow shear planes. Monitoring works and long-term supervisions in these types of landslides are useful to identify impending failures and take the right measures before they brought about large-scale destruction to the environment. 相似文献
124.
废弃矿山治理是目前政府十分关注的问题。介绍了田村沸石矿宕口环境治理和生态恢复工程,通过喷播复绿方案及实施,消除了边坡发生地质灾害的可能性,使景区的环境得到了一定的恢复,对其他地方的宕口整治有借鉴作用。 相似文献
125.
GIS在环境质量管理中应用的探讨 总被引:1,自引:0,他引:1
利用有效的辅助决策支持工具GIS,对我国环境质量管理应用系统进行设计和开发,已成为当前环境规划与管理领域的一项重要任务。GIS在国内外环境质量管理中的应用有大气污染监测与管理、环境地理信息系统、环境管理决策支持系统等。笔者介绍了环境质量管理GIS研究开发的基本思路与方法,本文从环境质量管理的系统特性、功能需求、设计方法等方面阐述GIS总体设计。皆在为从事环境质量管理方面的工作人员提供一些理论依据。 相似文献
126.
127.
城市发展与遥感技术应用——重庆市遥感综合研究成果概述 总被引:6,自引:2,他引:4
应用遥感技术开展城市国土资源、生态环境、城市建设及规划等领域的调查研究,这是适应现代城市快速发展的需要而开展的一项工作。1995年12月重庆市完成了遥感综合研究工作,所获取的大量调查数据、图像、图件和文字报告等资料,对重庆市的国土开发整治、城市管理、建设规划制定以及环境治理等方面均起到了重要作用。本文以该市遥感综合调查为例,介绍遥感技术在城市综合调查研究中的作用和城市主管部门对遥感综合调查研究成果的应用情况及效果。目的是促进遥感这门高新技术在更多的城市得到广泛应用。 相似文献
128.
This paper analyzes – chemically, mineralogically, and petrolographically – the patinas developed on several Mediterranean
monuments made with different stones (siliceous and carbonatic) in order to establish their origin and their evolution under
the present environmental conditions, and to evaluate the environmental parameters controling their development. Most of the
patinas show a common sequence of layers, which, from the outer to the inner zone, are: (1) present bioactivity and/or biological
remains, (2) gypsum-rich patina, and (3) calcitic brown to orange patina. Each one may exhibit different fabrics (from micritic
to stromatolitic) and may be more or less continuous and homogeneous. The main mineral components are calcite and gypsum,
but Ca-oxalates and Ca-phosphates have also been found associated to biological structures, as well as quartz and clays. The
different fabrics and textures have been interpreted as consequence of changes in the environmental conditions which seem
to be related to the biological activity, facilitating the growth of different organisms and leading to the development of
a deposit with distinct characteristics (fabric, texture, porosity, etc.). The gypsum-rich patina has been interpreted as
a sulphation of the underlying calcitic layer by the action of atmospheric pollutants or as dry or wet deposition from the
atmospheric dust. The mineralogy and texture of the patina is independent of the nature of the underlying rock and only in
few cases a micritization process has been observed as interaction between patina and rock. Recently, the penetration of endolithic
microflora produced drillings and the development of a fissuration system parallel to the surface, and thus the detachment
of the crust from the rock and even flackening of the rock itself has been observed. Consequently, under the present climatic
conditions in the Mediterranean basin, erosion is a more active process than deposition, and the crusts and patinas show a
tendency to disappear from the surface of the monuments.
Received: 3 November 1996 · Accepted: 10 September 1997 相似文献
129.
130.
台湾的红树林及其环境意义 总被引:2,自引:0,他引:2
本文概述了台湾现代红树林的分布及其与气候,海流,底质等环境条件的关系,并将台湾的红树林与邻区做了对比。中国东南部陆,海域沉积物中红树花粉的分布变化规律在一程度上反映了第四纪以来的环境变迁。 相似文献