福建琅岐岛土地演化与发展趋势

AN INVESTIGATION ON DEVELOPMENT AND EVOLUTION OF LAND IN LANGQI ISLAND

本文根据野外调查,并参考前人研究成果,讨论了闽江口琅岐岛的土地分异、土地演化与地质构造和构造运动、水文泥沙运动以及历史因素的关系,分析了今后该岛土地发展的趋势。

Langqi island is situated in the mouth of the Minjiang River. It was once a small rock island formed by hill lands. But now it becomes a large island consists of hills, plains and beaches, in which, plain accounts for the largest. since the upper pleistocene, first, the island has developed into a rock-accumulated island from a mainland-connected island Quaternary deposits go in order from river bed facies, flood plain facies, nerite facies, flood plain facies to river bed facies from lower stratum to upper stratum. Silt content and total silt discharge in the lower reaches of the Minjiang River have been increasing. The area of island expands constantly, especially in the south and west of the island. From now on, because the Minjiang River valley will be harnessed and Shuikou and Shaxikou hydropower stations will be built, silt content and total silt discharge in the Minjiang River will reduce gradually, which leads to a constant deposition in waters around the island though in a slow-down.