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本文通过分析现有河道水环境问题,阐述了传统河道拍摄与测量的难点与不足,说明了其测量范围广、限制因素多;精度要求高、技术难度大;涉及情况多、人为干预大的问题。针对上述问题,本文指出了无人机航测的优势与前景,论证了无人机定轨巡航、异常点全景航测、测绘网数字输出等功能在河道环境航测中的优势,说明了无人机航测技术在河道水环境治理中具有研究价值与应用前景。 相似文献
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鞍山市铁矿矿山地质灾害形成条件及对策研究 总被引:4,自引:2,他引:4
矿山地质灾害较其它地质灾害相比有其独特性。在鞍山铁矿区,排土场沉降不仅与采矿引起的地下水位下降有直接的联系,还与松散细粒土层、活动断裂有关;滑坡、泥石流地质灾害与地形地貌、水源条件及构造有一定的关系,更重要的是采矿活动产生的废石废渣为其提供了大量的物源;尾矿库灾害主要表现为:洪水漫顶、尾矿砂液化破坏、尾矿坝渗漏及管涌溃堤、尾矿坝滑塌破坏等。本文简要分析了鞍山市铁矿山主要存在的地质灾害类型(排土场地面沉降、滑坡、泥石流及尾矿库地质灾害)和形成条件并提出了防治地质灾害的对策。 相似文献
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中国古代地名研究的第二个方面是各种地名,特别是政区地名的沿革变迁。这是一个相当复杂的问题,沿革变迁造成大量的一地多名,假使不及时系统整理,就会使后代人面对大量存在的异名同地、异地同名等情况茫然无措。通常认为沿革变迁的研究即所谓历史沿革地理始于《汉书 ·地理志》,其实,在《汉志》以前,先秦文献中已经注意到地名的沿革变迁而加以记载,例如古本《竹书·纪年》魏今王下:“二月,城阳、向,更名阳为河雍,向为高平”。正是由于地名变迁在先秦早已开始,所以《汉书 ·地理志》才有必要加以整理研究。与《汉志》一样,《说… 相似文献
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论中国的非汉语地名续文/陈桥驿《汉书·西域传》无雷国条下:“北与捐毒,而西与大月氏接。”颜师古注:“捐毒即身毒,天笃也,本皆一名,语有轻重耳”。清徐松在《汉书·西域传补注》中指出:捐毒在葱岭东,为今布鲁特地,身毒在南山南,为五印度地。二国绝远,颜君比... 相似文献
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Anthropogenic impacts on hyperbenthos in the coastal waters of Sishili Bay, Yellow Sea 总被引:1,自引:0,他引:1
A survey on the hyperbenthic communities was carried out in the coastal waters of Sishili Bay in the Yellow Sea in July 2009, to investigate the impact of putative anthropogenic activities related to the presence of a sewage outfall, a harbor and an aquaculture site on the benthic ecosystem. An Agassiz net trawl was used to collect hyperbenthos at 10 sampling stations. Species, diversity, abundance, and biomass were analyzed against water sample data and historical data obtained from records from nearby Yantai City. Fifty-two species were identified in the region, of which Crustacea were the most abundant taxon, followed by Echinodermata. Dominant species included five crustaceans, two echinoderms, one mollusk and one fish species. The results of a BIOENV analysis show that the concentrations of NO3-N and Chl-a were slightly positively correlated with hyperbenthic community structure, while other factors were negatively correlated, including sediment grain size and the percentage of TN and TOC in sediment. Abundance- Biomass Comparison (ABC method) curves indicate that the hyperbenthos in Sishili Bay had been disturbed by putative sources of human activities. Eight out of 10 stations were classified as "moderately perturbed" to "perturbed". 相似文献
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历史时期绍兴地区聚落的形成与发展 总被引:5,自引:0,他引:5
本文论述的范围,指南起会稽山地,北抵杭州湾,东西各以曹娥江和浦阳江为界的地区,即历史时期的山阴、会稽两县和萧山县的一部分。本区南部是一片高度不超过一千米 相似文献