依据2004年表层及柱状样取样资料和以往多年近海区沉积物取样资料，对近年的底质变化特征进行了系统的分析。
Based on the data obtained from surface and columnar samples in 2004 and the data from deposits samples in the offshore waters in the past many years , variation characteristics of the bed-load in the recent years are analyzed .
年柱