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931.
西双版纳州地震活动特点及与环境因子的关系 总被引:1,自引:1,他引:1
本文揭示了西双版纳州东、西两部分地震(以澜沧江为界)的交替活动性、强震的近似原地重复性以及与环境因子的关系,进而指出本世纪90年代中至21世纪初该州的强震危险区主要在勐海县周围。最后,为实现逐年跟踪逼近预测,又提出了一种根据大气降水对地壳的加卸载动态变化具体化判断发震年份的方法。 相似文献
932.
论城市环境岩土工程研究 总被引:10,自引:4,他引:10
城市环境岩士工程问题是当前岩土工程和工程地质界研究的热点。本文认为,大城市不稳定性、环境水利与环境污染是其三个主要问题,并做了分析论证。根据系统科学思维原则,文中对人们感兴趣的研究方法论问题,提出了五点基本认识。 相似文献
933.
Sediment source tracing using environmental magnetism: A new approach with examples from Australia 总被引:1,自引:0,他引:1
G. G. Caitcheon 《水文研究》1993,7(4):349-358
Environmental magnetism can be used for sediment source tracing in situations such as stream junctions where two catchments deliver magnetically distinguishable, well combined average source mixes to a trunk stream. Consistent mineral magnetic parameter relationships show that spatially and temporally constant magnetic mineral assemblages occur along reaches of natural streams. For most of the confluence mixing situations examined it is possible to distinguish between tributaries using magnetic parameter relationships. Using these relationships, relative tributary contributions to the resultant downstream mix can be quantified. The method can be used for tracing suspended and bedload sediments so that the principal source catchments can be determined by a sequence of measurements at stream junctions along a drainage network. There is considerable potential for using this new and easily applied method for studies of sediment delivery processes and sediment movement in fluvial environments. 相似文献
934.
水环境中三氮转化的化学动力学规律及其在环境评价中的应用 总被引:5,自引:0,他引:5
在对“三氮”转化动力学规律进行总结分析、论证的基础上,建立了地表水和地下潜水环境中的“三氮”转化运移数学模型、通过理论—实验—应用三个环节,提出了一套水环境中氮污染的评价与研究的工作方法和程序。 相似文献
935.
矿山的环境地质研究初探 总被引:3,自引:0,他引:3
矿山采选冶事业发展,废水、废渣、废气排放量增加,对矿山环境造成污染,为科学地进行矿山环境治理,需开展矿山的环境地质研究,其任务是:(1)开展矿山初始时的环境地质调查,以利于查明环境污染程度,(2)编制矿山有关的环境地质图件,(3)研究矿山采选冶过程对矿山环境地质条件造成的影响,(4)研究矿山向城市化发展将出现的环境地质问题。湘西金矿在环境治理上取得一些成效,但环境地质问题仍不可忽视。 相似文献
936.
Frank H. Bolhan 《国际泥沙研究》1989,(1)
I. INTRODUCTION AND PERSPECTIVEIn planning, implementing and monitoring water and related resources developmentS, the effectsof erosion and sedimentation on man,s economic activities, his health and welfare and on the environment, have to be taken into ac… 相似文献
937.
A solid waste disposal site selection procedure based on groundwater vulnerability mapping 总被引:2,自引:0,他引:2
In this study, a new, GIS-based solid waste site selection tool (DUPIT) is introduced to obtain a systematic and unbiased
methodology during the evaluation phases of alternative solid waste disposal areas with regards to vulnerability to groundwater
pollution. The proposed tool is an index technique based on the linear combination of five different hydrogeological parameters
including Depth to groundwater table, Upper layer lithology, Permeability of the unsaturated zone, Impermeable layer thickness and Topographic slope. Five different categories are developed to classify each alternative based on the suitability of the site
for a solid waste disposal area. As a result, each site is ranked according to the contamination risks for groundwater resources.
The proposed technique is applied to the District of Torbali near Izmir, Turkey to determine the most appropriate solid waste
disposal site location. The Torbali application is implemented by using a GIS database developed for the area. Based on the
results of this application, the best alternative solid waste disposal site for Torbali is selected to be located in the northern
portions of the city where the groundwater table is deep, the permeability is low and the topographic slope is mild. 相似文献
938.
A water reservoir constructed for production of hydraulic energy and drinking water in the Riaño valley (León, northern Spain) receives leachates from polluted soils and spoil heaps from a site where small-scale As mining and smelting operations have been developed in the first half of the twentieth century. Water of the upper catchments of the Esla, Yuso and Orza Rivers is stored in this reservoir. The location of these abandoned mine works within the reservoir drainage basin suggested that the stored water could contain high As concentrations. In order to evaluate possible environmental risks, a preliminary soil and surface water geochemical survey has been carried out downstream of the Santa Águeda Mine. Total As concentrations in soils reach 23,800 mg kg?1 in soils and increase with depth, at least up to a depth of 80 cm. Total As concentrations in surface waters reach 890 μg l?1. Despite the fact that there is an important As input to the water reservoir, the water flow from the mine catchment is a negligible contribution when compared with the total volume of water inside the dam (0.07%). This fact considerably decreases the environmental risk associated with the presence of untreated spoil heaps containing As-rich minerals at Santa Águeda mine site. 相似文献
939.
The selection of the disposal site is probably the most important step in the development of solid waste management. In site selection, geology plays a determining role. This study evaluates the characteristics of the environment on the basis of the geological, hydrogeological and geo-engineering properties of the solid waste site of the Sivas city, Turkey. The area is underlain by the Oligocene-Miocene rocks which have limited aquifer properties. Thin Quaternary alluvium and soil cover overlie the Oligo-Miocene rocks, which are represented as well graded sand and inorganic silt of low plasticity. The Quaternary alluvium and soil cover are classified as inorganic clays having a low plasticity and the permeability varies from 1.2×10−6 to 3.11×10−6 m/s. These values are much higher than 1×10−8 m/s, which is accepted for waste disposal standards. Seepage waters have a potential to pollute the ground water and the Kızılırmak River, which is 500 m to the southwest of the waste disposal area and because the disposal site is close to the river, the potential for flash flooding poses a high pollution risk. The waste disposal area must be covered by clay layers or an impervious artificial membrane. In addition, seepage must be controlled and removed from the site. 相似文献
940.
Over 24 million plastic bags are consumed in Kenya monthly. More than half of the bags end up in the solid waste stream. Plastic bags now constitute the biggest challenge to solid waste management in Nairobi, the capital of Kenya and home to three million people. As a result, plastic bag waste has attracted great political and public attention, especially because the waste has myriad unique environmental problems. This paper seeks to unravel the problem of plastic bag waste in Nairobi through an urban political ecological perspective. Urban political ecology has done much to excavate economic, political, and cultural processes, as well as ecological dynamics that create and re-create urban environments. Little has been done in this context with respect to urban solid waste problems, with the exception of urban political ecology of environmental justice. However, research done within the context of urban political ecology of environmental justice has mainly focused on solid waste problems in the Western World, particularly USA. Drawing on research conducted in Nairobi, as well literature on business and politics, and solid waste management in Kenya, this paper examines the nature of plastic bag waste problem, its political–economic roots and implications for environmental justice. 相似文献