近三十年来曹妃甸岸线岛体时空演变特征分析

Spatiotemporal change characteristics of Caofeidian shoreline and island in the past three decades

在对1979年、1987年、1991年、1997年、2002年-2005年、2008年、2012年十个时期曹妃甸遥感影像图解译的基础上,从自然地理学角度对岸线和岛体历史演变趋势进行系统分析,得到曹妃甸岸线和岛体动态变化。研究结果显示,曹妃甸岛体面积在近半个世纪发生了较大的变化,由0.34 km2增加为227.34 km2;岸线整体表现为向海推进,1979年曹妃甸陆域岸线25.21%为自然岸线,之后自然岸线比例逐渐减少,自2002年起人工岸线占据了曹妃甸陆域岸线的全部,2012年岛体整体人工岸线长度较1989年自然岸线增长10倍之多;岛体在自然演变时期呈现中部侵蚀、两端淤积、端点延长、西向漂移且中心点逐步向大陆靠拢的变化特征,自2005年起自然状态岛体已不复存在。

Based upon Caofeidian remote sensing image interpretation in 1979, 1987, 1991, 1997, 2002, 2003, 2004, 2005, 2008 and 2012, it interprets shoreline and island historical changes and future trends from the physical geography point of view, so we get the dynamic change of Caofeidian shoreline and island. The analysis showed that there has been a dramatic shift in Caofeidian during the past half century with area increasing from 0.34 to 227.34 km2. The main trend of shoreline changes is moving seaward slowly. In 1979, 25.21% of shoreline was natural coastline in caofeidian, after that the proportion of natural coastline gradually reduced. Artificial coast accounted for the whole shorelines since 2002 in Caofeidian. The growth of artificial coastline is ten times more in 2012 than natural coastline in 1979. The change of island is proved to be middle erosion, siltation at both sides, endpoint extending, western drifting and the central point becoming closer gradually to the land in the natural evolution period. The natural state of Caofeidian does not exist any more.