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Dong‐Gang Guo Bing‐Qing Zhao Tie‐Liang Shangguan Zhong‐Ke Bai Hong‐Bo Shao 《洁净——土壤、空气、水》2013,41(10):1018-1026
The influence of soil physicochemical properties and the relationship between the plant community and edaphic factors have been studied through monitoring the community dynamic parameters and analyzing the soil properties from four plant plots at the Pingshuo opencast coal mine eco‐reclamation area. The results are obtained as follows: (1) the law of the quantity variation of total N and available K is affected by the different kinds of plant configuration mode. It is Robinia pseudoacacia + Pinus tabuliformis (SIV) > R. pseudoacacia (SV) > R. pseudoacacia + P. tabuliformis (SI) > R. pseudoacacia + Ulmus pumila + Ailanthus altissima (SIII). The quantity is close to or exceeds the level of the original geomorphology. The average content of available N has the following order: SIV > SI > SIII > SV; the average content of available P SV > SIII > SIV > SI, both are far below the level of the original geomorphology; pH SIV < SIII < SI < SV; bulk density SI < SIV < SV < SIII, moisture content SIV > SIII > SI > SV; in the soil layer of 20–40 cm, except the available P, other physicochemical factors are in accordance with the factors of the surface soil; (2) the population average density, height and diameter at breast height (DBH) have no obvious relevance with the average density of the stumpage; (3) the average density, height, and DBH of R. pseudoacacia are closely related to pH and the content of available N and available P and all the index can be fitted by the equation of linear regression of the edaphic factors mentioned above. The principal component analysis shows that the magnitude of the impacts of three kinds of edaphic factors on the R. pseudoacacia population has the following order: pH > available N > available P. The average density of U. pumila is closely related to the moisture content of the soil. This regression model can be used to direct the cultivation and propagation of R. pseudoacacia and U. pumila population at the mine eco‐reclamation area. 相似文献
375.
Tidal flats, which are important reserved land resources, have a vital role in climate change. To evaluate the contribution of coastal saline soils to carbon sequestration, field tests were performed over a 3 year period at the Dafeng Wanggang Experimental Station in Jiangsu Province, China. Six artificial agro‐ecosystems, including wasteland (WL), freshwater fish culture (FC), Sesbania culture (SC), barley culture (BC), mixed culture of fish and Sesbania (MCFS) and mixed culture of fish and barley (MCFB), were established according to developmental processes of coastal saline soils. At the initial stage of tidal flat reclamation, the soil organic carbon (SOC) increased by 59.4 t ha?1 in the FC system during 3 years, which was much higher than that of the WL system (40.7 t ha?1). When the tidal flats evolved into high saline soils, the MCFS system sequestered SOC more effectively than the FC or SC systems with increases of 53.1, 16.9 and 8.3 t ha?1, respectively. Subsequently, in the low saline soils, the maximum soil carbon sequestration was obtained in the MCFB system (35.8 t ha?1) followed by the BC (17.5 t ha?1) and FC (13.5 t ha?1) systems. Therefore, proper development of tidal flats to farmland and the subsequent establishment of optimised artificial agro‐ecosystems make an important contribution to carbon sequestration and climate changes in coastal areas. 相似文献
376.
SPATIAL-TEMPORAL VARIATION OF HEAVY METAL ELEMENTS CONTENT IN COVERING SOIL OF RECLAMATION AREA IN FUSHUN COAL MINE 总被引:3,自引:2,他引:1
Grid method is employed for sampling covering soil at the test field, which is reclamation area filled bycoal mining wastes for cropland in the Fushun coal mine, Liaoning Province, the Northeast China. The soil samples aretaken at different locations, including three kinds of covering soil, three different depths of soil layers and four differentcovering ages of covering soil. The spatial-temporal variation of heavy metal element content in reclamation soil is studied. The results indicate that the content of heavy metal elements is decreasing year after year; the determinant reasonwhy the content of heavy metal elements at 60cm depth layer is higher than that at 30em depth layer and surface is fertilizer and manure apphcation; the metal elements mainly come from external environment; there is no metal pollution comingfrom mother material (coal mining wastes) in plough layer of covering soil. 相似文献
377.
LAND RECLAMATION PROCESS IN NORTHEAST CHINA SINCE 1900 总被引:2,自引:1,他引:1
Landuse/coverchange(LUCC)isafocalthemeandemergingissueinthestudyofglobalenvironmentalchange.Humanmodificationsandalterationstotheenvironmentcauseimpactsonthesurfaceoftheearth,threatenglobalsustainabilityandlivelihoodsystems,andcontributetochangeinthebiogeochemicalcyclesoftheearth,whichinturnaffectatmosphericlevelsofgreenhouseandothertracegases.ConsequentlytheInternationalGeosphere-BiosphereProgram(IGBP)andtheInternationalHumanDimensionsProgram(IHDP)initiatedLUCCProgramtodevelopabette… 相似文献
378.
WISE EXPLOITATION OF NEWLY GROWING LAND RESOURCES——An Assessment on Land—use Change of Chongming Island Using GIS 总被引:4,自引:1,他引:3
Chongming Island, the third largest island in China and the largest alluvial island in the world, is situated in the north
of Shanghai Municipality at the mouth of the Changjiang (Yangtze) River. Along the fertile and prosperous sea coast there
are a total area of over 120×103ha, with a population of 735 000, accruing some 500ha of new tidal land resources come from silt, sand and mud carried by
the Changjiang River every year, extending about 140m per year. This dynamic process of alluvial growth has run for some 1500
years. Mudflat on Chongming Island at the mouth of the Changjiang River is a resting ground for migratory birds and host more
than a hundred species, including rare cranes and geese. But the local people keep reclaiming the tidal land for economic
development. Obviously, it is crucial to have a well-concerted plan for future exploitation. In this study, we attempted to
investigate the status changes of land use and wild life habitats on Chongming Island in recent 10 years, and then analyzed
different human activities and their effects on wild life habitats using satellite image data (1990, 1997 and 2000) as well
as field survey. Based on the analysis, this study explored the relationships between island growth and land use/cover change
(LUCC), predicted what the habitat would be like in the future and tried to find more effective use of this new growing resource.
At last, this study provided some preliminary management plans for Chongming Island that will coordinate the development of
local economies and the conservation of wild life and their habitats.
Foundation item: Supported by WWF (World Wildlife Fund) China Program (CN0079.08).
Biography: ZHAO Bin (1969 - ), male, a native of Hubei Province, Ph. D., specialized in landscape ecology and biodiversity
information system management. 相似文献
379.
天津滨海新区被提到国家总体发展战略后,随着经济持续发展、城市化进程不断加速及产业转移,进行了大规模围海造陆,在拓展土地空间的同时,也造成了相当多的环境问题。利用滨海新区由陆到海的3条水文地质剖面获取的地下水动态变化监测数据和土壤含盐量测试结果,开展了围海造陆对沿海低地浅层地下水环境的影响研究。结果显示:1受围海造陆影响,对应的沿海低地浅层水位已经出现由陆到海逐渐增高的现象,造成地下水位反向倾斜,阻碍了地下水径流和排泄;2由陆到海浅表土壤全盐量出现逐渐增高的特征,在浅层地下水反向径流作用下,东部区域大量的盐分将被携带至沿海低地,使沿海低地盐渍化程度加重,严重影响到湿地保护和生态建设;3围海造陆对海岸带生态环境的影响是一个长期缓慢的过程,应持续监测近岸海域和陆域沿海低地生态环境的变化情况,以便提出合理的修复建议。 相似文献
380.
海岸围垦工程实施后,将会改变地形及边界条件,并对工程区的水动力及泥沙冲淤产生影响。针对淤泥质海岸的特点,选取适当的经验参数,在平面二维潮流的基础上应用半经验半理论的泥沙冲淤计算方法,并考虑波浪对沉降机率和水流挟沙能力的影响,建立了淤泥质海岸围垦促淤的计算方法。同时,以舟山市钓梁围垦二期工程作为实例进行分析,利用工程区实测水文泥沙资料,确定当地挟沙能力公式参数,并对区内进行冲淤计算,得到冲淤强度的分布,通过实测资料的对比,取得了满意的结果。其中,考虑波浪效应后的计算结果更符合实测资料,波浪对该围垦工程促淤效果的影响比例在0.76%~17.5%之间,不能忽略。 相似文献