莱州湾扇贝养殖区表层沉积物质量评价

Quality Evaluation of Surface Sediments in Scallop Culture Area in Laizhou Bay

2015年4—11月对莱州湾4个扇贝养殖区进行了表层沉积物pH、氧化还原电位、硫化物、总磷、总氮、有机碳以及细菌(弧菌和异养细菌)等8个指标检测,并采用有机污染指数法和内梅罗环境质量综合评价法对其进行了评价。通过分析各指标月际变化及来源,试验结果表明,4个养殖区表层沉积物pH和氧化还原电位变化分别为7.33~8.30和-368.30^-170.30mV,属于中性—弱碱性的高度还原态环境;总氮、总磷、总有机碳和硫化物的含量分别为0.038~0.897mg/g、0.131~0.554mg/g、0.029%~0.560%和1.66~184.11mg/kg,除总氮在7—10月出现不同程度的超标之外,其他指标均处于安全范围内;异养细菌和弧菌数量的变化分别为3.0×102~8.2×104 cfu/g和0.5×103~7.9×103 cfu/g(湿质量),各养殖区之间差异较小。综合评价结果表明,莱州湾扇贝养殖区表层沉积物环境整体处于良好状态,但应控制氮元素的输入。

pH,oxidation-reduction potential（ORP）,and contents of sulfides and nutrients such as total phosphorus（TP）,total nitrogen（TN）,and total organic carbon（TOC）as well as heterotrophic bacteria and Vibrio were determined in 4 scallop culture areas from April to November in 2015.The monthly variation and pollution status of surface sediment in different culture areas were analyzed by organic pollution index and Nemerow comperhensive quality.The results showed that the sediment was neutral-weak allkaline belonging to the highly reduced state since the pH and ORP in sediment were ranged from 7.33 to8.30 and from-368.30 mV to-170.30 mV,respectively.The concentrations of sulfide,TN,TP and TOC in sediment were ranged from 1.66 mg/g to 184.11 mg/kg,from 0.038 mg/g to 0.897 mg/g,from0.131 mg/g to 0.554 mg/g and from 0.029%to 0.560%,respectively.With the exception of TN,other indicators were in a safe range;ranges of heterotrophic bacteria and Vibrio were from 3.0×10^2 cfu/g to8.2×10^4 cfu/g and 0.5×10^3 cfu/g to 7.9×10^3 cfu/g（wet weight）in account,and had little difference in different scallop culture area 3.Comprehensive evaluation indicated that the breeding environment in different scallop culture areas of Laizhou Bay was in good condition,even though nitrogen input should be controlled.