杭州西湖水域微生物的生态调查

对杭州西湖水域微生物生态调查结果表明:(1)有机营养型细菌在富营养化程度较重的岳湖分布较多,而无机营养型细菌在水质较好的小南湖丰度较大;(2)许多微生物类群在温度较高的季节数量反而较少;(3)西湖经综合治理后,异养型细菌和大肠菌群数量有显着减少,但近年又有增加的趋势;(4)西湖水体中的微生物以假单胞菌属的细菌较多,而底泥中芽孢杆菌属的细菌占优势。  

STUDIES ON THE ECOLOGICAL DISTRIBUTION OF MICROORGANISMS IN THE WEST LAKE,HANGZHOU

The ecological distributions of different microbial physiological groups in West Lake, Hangzhou were studied from 1995 to 1996. The heterotrophic bacteria including ammonifiers, cellulose decomposers, nitrate reducers and denitrifiers were rich in Yuhu Lake, where the water was eutrophic; while autotrophic bacteria, shch as ammonia oxidizers and nitrite oxidizers, were more common in Xiaonan Lake where the water quality was relatively good. Ammonifiers and cellulose decomposers had the negative relations with ambient temperature, no matter whether they were in the water body or in the sediment. Compared with historical data, it was founded that the heterotrophic bacteria and coliform groups were decreased significantly after comprehensive treatment of West Lake in 1986, but recently they have increasing trend. After determining 78 heterotrophic strains isolated in water body in Apr. 1996. The authors found that Pseudomonas and Enterobacteriaceae were the dominated species; in 117 heterotrophic strains isolated from the sediments in Oct. 1995 and Mar. 1996, about 50% were belonged to Bacillus and about 24% were Enterobacteriaceae. According to the data supplied by co-operators, it was founded that ammonifiers, cellulose decomposers, nitrate reducers and denitrifiers in the water body had more constrained relations with total nitrogen than with total phosphorous. It was also founded that these bacteria had the negative relationship with the densities of phytoplankton and zooplankton.