南沙港网箱养殖水域沉积环境质量评价

2007-01至2007-11分4个航次对宁波南沙港网箱养殖区沉积物环境质量状况进行了现场调查，利用MOM—B系统的三个子集参数对沉积环境质量进行了评价。结果表明：子集1得出2007-01的平均分数小于0．5，而-2007—04、2007—07以及2007—11的平均分数均大于0．5；子集2得出4个季节沉积物的pH和氧化还原电位变化范围分别为7．15—8．33和-197．5m～-105my；子集3得出4个航次得到的平均分数介于4和10之间；综合3个子集的结果来看，南沙港网箱养殖区沉积物环境质量状况冬季为2级，春季、夏季和秋季均属于4级严重污染状态。

Assessment on the Sediment Quality Condition of Cage Culture Area in Nansha Bay

On basis of field data measured during 4 cruises from January to November 2007, the sediment quality and pollution degree in Bansha bay of Ningbe city were assessed by management system named Modelling - Ongrowing fish farms - Monitoring system（MOM）. The results showed that the mean score of 2007 - 01 was less than 0. 5, while the mean score of another season was larger than 0. 5, which means the sediment condition is considered unacceptable（ condition 4） except 2007 - 01 which is in condition 1,2 or 3 according to the Group 1 parameter. The variation range of pH and Eh was 7. 15 - 8.33 and - 197. 5 mv - - 105 my respectively means the sediment was in condition 2 level according to Group 2 parameters. Combining the conditions determined by the three groups of parameters, it could be found that the sediment condition of Nansha cage culture area was in condition 2 in Winter and condition 4 in Spring, Summer and Autumn.