中文摘要：

2006年6月至2007年5月长江入海径流量较多年平均减少1／3，为特枯水文年。根据长江口南槽江亚北水道实测盐度等资料。分析了该特枯水文年的盐水入侵状况。结果显示：研究区该时间段几乎均为盐水所占据，96．6％的天数处于盐水入侵状态；与常年相比，盐度具有年变幅大、洪枯季差异小、高盐月份多的特点。研究表明：盐水入侵主要受径、潮流控制，多发生在小径流量-大潮期；大通径流量30000m^3／s是盐水入侵与否的阈值。

英文摘要：

From June 2006 to May 2007, the water discharge of Yangtze River into the sea reduced about 1/3 of multiyear average, which is an extraordinary dry year. On the basis of measured salinity data in the South Passage of Yangtze River Estuary, results indicate that the study area was occupied by saline water almost all year round, and salt intrusion occurred in 96.6% days in the year, and the salinity presented great annual variations, small difference between flood and dry seasons, and much more high-salinity months than normal year. Further, studies suggested that the salt intrusion was controlled by runoff and tidal current, and occurred in the low discharge and spring tidal period; river discharge 30000 m^3/s at Datong station is the threshold of salt intrusion or not.