浙江近岸海域细菌学分析

调查分别于1998年5～6月和9～10月进行2个航次,对浙江近岸海域30个站位的表层和底层海水样品进行了细菌学检测.结果表明,第一航次以浙中海域的粪大肠菌群和异氧菌总数最高,第二航次以宁波海域粪大肠菌群最高,而异氧菌总数以三门湾最高.两个航次表层和底层海水粪大肠菌群超标率最高为16.7%,异氧菌总数超标率均达89.3%以上.第一、二航次表层海水粪大肠杆菌单项污染指数平均值分别为0.229±0.452和0.375±0.630,异氧菌总数单项污染指数平均值分别为8.6±11.178和12.8±18.796.底层海水中粪大肠杆菌单项污染指数仅在第一航次宁波近岸的JN-1108站位超标;异氧菌总数单项污染指数第一、二航次最大值分别为37.0和18.0, 也出现在宁波近岸的JN-1108站.分析显示,粪大肠菌群与异氧细菌总数存在一定的正相关关系,其相关系数r2=0.34.结果表明,浙江近岸海域已明显受到异氧菌的污染, 宁波近岸海域已遭到粪大肠杆菌和异氧菌的污染.

Bacterial analysis in the water samples from the seacoast of Zhejiang Province

Both surface and lower layer water samples were collected from 30 coastal areas of Zhejiang province for bacteriological analysis during the periods of May to June and September to October 1998. During the voyage, our investigation showed that the highest numbers of coliform bacteria and het-erotrophic bacteria were detected in the mid-coastal water areas of the province, while during the second voyage, the highest number of coliform bacteria and heterotrophic bacteria were found respectively in Ningbo coastal water Sanmen bay. Of the samples from both the surface and lower layer water, 16. 7% had coliform bacteria above the threshold and over 89. 3% had heterotrophic bacteria above the threshold during two voyages. The average contamination of coliform water from the surface layer for coliform bacteria were 0. 229 and 0. 375, respectively, during the first and second voyages; corresponding indices for heterotrophic bacteria contamination were 8. 6 and 12. 8 respectively. For the lower layer water, the samples with the numbers coliform bacteria (index = 37. 0) and heterotrophic bacteria (index = 18. 0) above the threshold were found in the JN-1108during the two voyages. Statistical analysis indicated a positive correlation between the clone formula unit (cfu) of coliform bacteria and the number of heterotrophic bacteria, and the coefficient was r2 = 0. 34. The results revealed that the coastal water of this province has already been contaminated by heterotrophic bacteria, and the coastal water at Ningbo has encountered the contamination by both coliform bacteria and heterotrophic bacteria.