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长江是我国第一大河,水量充沛,江流湍急,每年挟带近5亿吨泥沙倾吐入海。长江出三峡后,就进入广阔的中下游平原,其间有山丘阶地,控制着长江的流势。广阔的冲积平原,由于河床边界物质疏松,抗冲性弱,受水沙冲击后,江岸就发生变迁。当你打开大比例尺地形图、航空象片或到实地观察一下时,就会发现在长江中下游两岸的泛滥平原上还保留许多古河道的残迹,它是长江原来的流路。古河道像长龙一样,弯弯曲曲盘踞在长江中、下游两岸。
The Yangtze River is the largest river in our country with abundant water and fast-moving rivers. Nearly 500 million tons of sediment are poured into the sea every year. After the Three Gorges came out of the Yangtze River, it entered the vast plains of the middle and lower reaches of the Yangtze River. During this period, there were hills and terraces that controlled the flow of the Yangtze River. The vast alluvial plain, due to the river bed boundary material loose, weak impact, by the impact of water and sand, the river bank changes. When you open large-scale topographic maps, aerial photographs or observe from the field, you will find that the remains of many ancient rivers remain on the floodplains along the banks of the middle and lower reaches of the Yangtze River. It is the original flow path of the Yangtze River. Ancient river like a long queue, winding entrenched in the middle and lower reaches of both sides.