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991.
通过铬在包气带的垂直渗滤试验探讨了铬对地下水污染的机制,认识到地下水铬污染的主要途径是通过包气带渗入,铬在包气带中的垂直迁移性好,铬进入含水层后,在水动力条件及浓度的影响下,可发生运移—弥散作用,造成大面积地下水污染,严重影响生态环境。 相似文献
992.
针对芒市河污染现状,结合近年收集的相关资料,对芒市河流域污染源、水质现状进行了全面调查与评价,找出了主要污染物及污染源。计算了芒市河水环境容量、污染物削减量,为做好水资源的管理与保护、改善水环境质量、促进水资源的可持续利用提供科学依据。 相似文献
993.
Alexey Viktorov 《Mathematical Geology》2007,39(8):735-748
The estimation of the risk caused by hazardous geological processes is a common problem. The aim of this paper is to present
a method for solving problems involving a wide spectrum of diffuse exogenous geological processes, based on the mathematical
morphology of landscapes. Diffuse processes develop as random rounded sites within certain areas and include karstification,
subsidence, thermo-karstification and aeolian processes. Model assumptions take into consideration spatial and temporal randomness
of occurrence, independent growth under occasional conditions, and cessation of growth given a ‘stop factor’, with transformation
into degenerate sites. Based on these model assumptions, the following probabilities of impact by diffuse exogenous geological
processes are solved for analytically. Firstly, the probability of impact on engineering constructions of round shape given
the size of the diffuse processes and the known average impact risk; secondly, the probability of impact on small engineering
constructions (points); and lastly, the probability of impact on linear engineering constructions of specified length. The
computed impact probabilities are verified in various areas within Western Siberia. 相似文献
994.
Phenolics’ occurrence in surface water of the Dniester river basin (West Ukraine) with the definition of the natural background
is studied. The main attention is given to the Upper Dniester basin and its tributary Stryj as the parts of the Sub-Carpathian
oil- and gas province with the numerous objects of oil industry. The total amount of phenolics in water is studied. Phenolics’
concentrations from the first micrograms to the first milligrams per litre have been found in the surface water of the region.
The natural background is defined as 0.012 mg l−1 for the areas out of the industrial influence. The anthropogenic part of phenolics is caused mainly by oil industry. The oil-producing
objects provide the main phenolics’ releases in the region, due to the low protection level of mechanical facilities as well
as to breach of technological norms on the oil-extracting objects. A man-made pollution of the basin water has a regional
character and the natural self-purification processes seem to be insufficient for its neutralisation on the plains in particular. 相似文献
995.
Assessing pollutions of soil and plant by municipal waste dump 总被引:1,自引:0,他引:1
Changli Liu Yun Zhang Feng’e Zhang Sheng Zhang Miying Yin Hao Ye Hongbing Hou Hua Dong Ming Zhang Jianmei Jiang Lixin Pei 《Environmental Geology》2007,52(4):641-651
Research is few in the literature regarding the investigation and assessment of pollutions of soil and plant by municipal
waste dumps. Based upon previous work in seven waste dumping sites (nonsanitary landfills) in Beijing, Shanghai and Shijiazhuang,
this study expounds the investigation and assessment method and report major pollutants. Using relative background values,
this study assesses soil pollution degree in the seven dumping sites. Preliminary conclusions are: (1) pollution degrees are
moderate or heavy; (2) pollution distance by domestic waste that is dumped on a plane ground is 85 m; (3) the horizontal transport
distance of pollutants might be up to 120 m if waste leachates are directly connected with water in saturated soils; (4) vertical
transport depth is about 3 m in unsaturated silty clayey soils. Furthermore, using relative background values and hygiene
standards of food and vegetable this study assesses the pollutions of different parts of reed, sorghum, watermelon and sweet-melon.
It is found: (1) in comparison with the relative background values in a large distance to the waste dumping sites, domestic
wastes have polluted the roots and stems of reed and sorghum, whereas fine coal ash has polluted the leaves, rattans and fruits
of watermelon and sweet-melon; (2) domestic wastes and fine coal ash have heavily polluted the edible parts of sorghum, water
melon and sweet-melon. As, Hg, Pb and F have far exceeded standard values, e.g., Hg has exceeded the standard value by up
to 650–1,700 times and Cd by 120–275 times, and the comprehensive pollution index is up to 192.9–369.7; (3) the polluted sorghum,
watermelon and sweet-melon are inedible. 相似文献
996.
徐州市矿山环境地质问题及防治对策 总被引:1,自引:0,他引:1
徐州市为我国著名的煤炭生产基地,是全国主要矿业城市之一。随着社会经济特别是矿业的不断发展,该市的矿山环境问题日益突出。如煤矿、铁矿地面塌陷破坏的土地21309hm2,开山采石占用与破坏土地1430hm2,造成矿区10万人失去了赖以生存的土地;矿坑排水、洗(选)煤水排放、煤矸石堆放、回填塌陷地及开山采石造成矿区水、土、气环境严重污染;井下采矿大量疏干排水造成水资源枯竭;采煤塌陷地破坏水利工程及道路等地表设施;开山采石影响自然景观及城市景观……。针对上述状况,文章从构建"绿色徐州"及"生态徐州"角度出发,提出一系列防治对策建议:①加快矿山环境保护与治理规划编制,严格矿山环境准入制度;②创建"绿色矿山",走可持续发展的道路;③重视采煤地面塌陷区的土地复垦,建设生态农业示范区;④加大废弃资源的综合利用,挖掘矿山旅游资源。 相似文献
997.
张理华 《云南地理环境研究》2007,19(4):121-127
选取淮河于支流19个省界断面监测点52个月的监测数据,进行科学处理,从地理环境整体性、系统性的角度建立了水环境污染模型,揭示淮北平原水体污染的时空变化规律,讨论了水系结构对水体污染的影响。综合分析了安徽淮北平原水环境整体性污染的原因在于区域人口密度过高,与社会、经济和环境保护不协调;处于生态脆弱地带;生产方式落后,经济水平处于低谷。提出了重在治本,改善生态环境,活跃地表径流;加快经济发展,为环境保护提供经费支持;整治淮河水系,上中下游形成合力;提高环保意识,依法治污等观点。 相似文献
998.
999.
The non-point source pollution in livestock-breeding areas of the Heihe River basin in Yellow River 总被引:4,自引:0,他引:4
Hongguang Cheng Wei Ouyang Fanghua Hao Xiyan Ren Shengtian Yang 《Stochastic Environmental Research and Risk Assessment (SERRA)》2007,21(3):213-221
A GIS-based distributed soil and water assessment tools (SWAT) model was used to simulate the runoff, sediment yield and the
load of the non-point source pollution in the Heihe River basin, which is a tributary and main water supply source of the
Yellow River. It is a typical stockbreeding area, and its industry and agriculture are not well developed. The main pollution
source of the Heihe River was livestock related non-point source pollution. With GIS and remote sensing techniques, a database
of non-point source pollution in the Heihe River basin was established. The SWAT model was parameterized for this area. The
pollution load and transportation rules such as nitrogen were illustrated. After several years of hard work, the situations
of point source pollution were more and more accurate. This paper provided an effective way to assess and calculate the pollution
load in the wide agriculture area in China. With the help of historical data formulated parameters, the non-point source load
and the theory of pollution load distribution were illustrated about the Heihe River basin. In 2000, the soluble N load in this area was 1.06 × 106 kg. By the simulation, the main pollution sources were in the south east of the basin, where
the pasturing areas located in the south-east of Ruoergai County and in north of the Hongyuan County. 相似文献
1000.