基岩海岸海水入侵特征及对策——以长岛县南北长山岛为例

CHARACTER AND COUNTERMEASURE OF SEAWATER INTRUSION ON BEDROCK SUCH AS SOUTH AND MORTH CHANGSHAN ISLAND

山东省长岛县南、北长山岛地下海水入侵于20世纪70年代,至90年代有明显扩大。海水入侵存在海湾层状沉积体孔隙式层状入侵、岩岸裂隙式脉状入侵和层状基岩层隙式面状入侵3种基本形式 ;造成海水入侵不断加剧的原因一方面受大气降水的明显影响 ,另一方面由于当地经济与社会发展带来的地下淡水过量开采引起 ,形成了地下水质恶化与城镇和人口稠密区、机井密集区相对应的社会 地质灾害空间组合。防止海水入侵、切实保护地下淡水资源 ,首先应采取重点地段上实施拦蓄结合的地下水工程 ,也可以借用天然形成的糜棱岩带作为拦蓄工程基础 ,以节约资金投入 ;其次是减少地表径流与地表蒸发 ,扩大地下淡水量 ;

The observation from the water-board of Chang Dao County shows that the quality of underground water trends toward deteriorating and the intruded range is enlarging since the 1970's to the 1994's in South and North Chang Shan Island. According to the character about seawater invasive location deduced from the condition of water geology of the island above, there are three kinds of seawater invasion: the layered invasion of the gap of the layered deposits in ocean bay; the veined invasion of the gap in shore; and the faced invasion of the gap of layered rock. It is considered that seawater invasion is due to the interaction of nature and mankind, the change of rain, the human activities about building, the development of society and economy and so on. Several methods combining the character of island county suggested that include decreasing ground direct-flower, building the project for holding seawater up, developing new water resources and saving water.