长牡蛎夏季死亡与养殖环境及自身体质关系的初步研究

Study on the relationship between pacific oyster Crassotrea gigas summer mortality with culture environment and organism condition

关键词:  长牡蛎  夏季死亡  桑沟湾  养殖环境  SOD

Key words:  Pacific oyster  Summer mortality  Sanggou Bay  Culture environment  SOD

摘要:

选取桑沟湾和爱连湾两个典型牡蛎养殖区为研究对象，调查了两个海区高温季节牡蛎的死亡情况，监测了不同养殖区的水温、盐度、pH和DO等环境指标，并测定了牡蛎体内超氧化物歧化酶（SOD）活性和生长指标的差异，初步探讨了桑沟湾养殖长牡蛎夏季高温死亡的原因。结果表明，实验期间（5~10月）桑沟湾崖头养殖海区（E122.498，N37.151）长牡蛎夏季累积死亡率为37%，最高死亡率出现在8月17日，高达51%，而爱连湾养殖海区（E122.582，N37.179）的累积死亡率仅为2.5%，最高死亡率出现在9月28日，为4.5%。单因子方差分析（ANOVA）表明死亡率与水温具有很强的正相关（R=0804，P<001），与溶氧呈明显负相关（R=-0.377，P<0.01）；死亡率与体重、软体湿重、性腺湿重等生长状况指标呈明显的负相关（R分别为-0.690、-0.498、-0.358），与SOD活性呈正相关（R=0.21，P<0.05）。

Abstract:

Pacific oyster Crassostrea gigas summer mortality frequently occurs in Sanggou Bay recent years，but the oyster appears low mortality rate in its neighboring region Ailian bay. In this study, two typical Pacific oyster culture areas of these bays have been selected as experimental sites. The environmental factors including water temperature, salinity,pH and DO, superoxide dismutase (SOD) activity and growth situation of oysters have been monitored, and the oyster summer mortalities of two sites have been researched. The reason of Pacific oyster summer mortality in Sanggou bay has been analyzed. The results show that: in experiment period (from May to October), the total mortality rate was 37% in Yatou marine culture region of Sanggou bay (E122.498，N37.151), the highest mortality rate that appeared on August 17 was 51%. The total mortality rate was 2.5% in Ailian bay (E122.582, N37.179), the highest mortality rate that appeared on September 28 was 4.5%. One way ANOVA results show that: the mortality rate has significant positive correlation with water temperature (R=0.804, P<0.01), negative correlation with the dissolved oxygen (R=-0.377, P<0.01), negative correlation with body weight, soft weight and gonad weight and so on (R=-0.690,-0.498,-0.358, respectively), positive correlation with superoxide dismutase activity (R=0.21,P<0.05).