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兴凯湖北部平原的发展与湿地的形成 总被引:6,自引:0,他引:6
兴凯湖北部平原和湿地的形成与发展,过去研究的较少。在国家科技攻关时对其进行了专门调查研究,了解到它是在新生代断陷盆地的基础上发展起来的湖积冲积平原。发现自晚更新世TL63900a±3190a至TL12190a±610a间,有5道沙堤在兴凯湖北部平原上形成,第Ⅴ道沙堤以南的湖积平原,宽15.5km,由3道湖成沙堤和2道支堤将其分隔成一些湖滩、洼地和小湖,形成湖滩湿地和洼地湿地(类似海岸带的泻湖湿地)。平原的形成是沼泽湿地发生发展的基础,随着湖岸线的迁移,沙堤之间的湖滩、洼地和小湖,水体不断沼泽化,大约于9000a前以来发育泥炭沼泽,在距今7500a至5000a间和3000a至2000a间气候较为湿润,沙堤间滩地、洼地和松阿察的古河道河漫滩地带广泛发育沼泽湿地,不断进行泥炭积累。第Ⅰ道与第Ⅱ道沙堤之间的沼泽湿地,属强度沼泽化地区,生长小叶章(Calamagrostis angustifolia)和毛苔草(Carex lasiocarpa),是兴凯湖北部平原难以开发利用的湿地。 相似文献
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The practice has proved that it is an economic and effective method to investigate placer gold deposit by using multi-level information sources of remote sensing and multi-variate analysis methods, especially for the area with a sparse population and difficult condition like the Da Hinggan Mountains, China.The information sources used in our work includes Landsat TM, aerial infrared photography and their mosaic image maps and enlarged photos with different scales. According to statistic data, in the study area the gold-bearing rocks are mainly granite, alaskite, granodiorite and some old metamorphic rocks. On gold-bearing geological structures, the fault zones in the four directions (NE, NNE, NW and EW) are obvious, in which NNE and EW are the most key fault zones. On fluvial geomorphology the flow courses stored placer are in the tributaries of the 4th and 5th levels, especially in straight or slight curve reaches. On the basis of analysis the interpretative signs were set up, and the interpretative wo 相似文献
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STUDYONMODELFORREMOTESENSINGESTIMATIONOFMAIZEYIELDLiuZhaoli(刘兆礼)HuangTieqing(黄铁青)WanEnpu(万恩璞)ZhangYangzhen(张养贞)ChangchunInsti... 相似文献
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