哑铃湾网箱养殖海区表层沉积物磷的含量特征

在哑铃湾不同养殖历史网箱下、距离网箱50m和100m以及对照海区共布设8个采样点,于2002年4月~2003年1月分四季采集表层沉积物样品,对沉积物中总磷、无机磷和有机磷进行了测定,分析了调查区磷的空间分布和季节变化特征。结果表明:哑铃湾海水养殖网箱下沉积物磷含量明显高于对照点,沉积物中总磷是对照点的3.71~9.99倍。养殖历史越长,沉积物中的磷含量越高;网箱养殖引起的沉积物磷累积仅限于网箱下及距离网箱50m范围内,对距离100m以外的海区影响较小;沉积物中的无机磷占70%以上,以无机磷为主;养殖历史较长的东升村养殖区沉积物磷的季节变化明显,有机磷的变化与养殖活动密切相关。

Phosphorus Contents in Sediments from Cage Culture in Yaling Bay

Sediments were sampled at eight stations under fish cages 50 and 100 m away from the cages in Yaling Bay from April 2002 to January 2003. Total phosphorus, inorganic phosphorus and organic phosphorus contents were determined in the sediments. The results showed that the inorganic phosphorus was the predominate composition in total phosphorus. The phosphorus contents in the sediments were significantly 2.718.99 times higher under the cages than the control station, and the longer time the cage farming was kept, the higher the phosphorus levels in the sediments were. The impact of cage culture on sediment phosphorus was limited to the 50 m radius areas from the cage. The seasonal changes in the sediment phosphorus levels were observed at Dongsheng station and the changes in the organic phosphorus were closely related to the cage culture.