冬季菲律宾蛤仔育苗系统几类主要细菌数量变化

Change in Main Bacterial Groups in Manila Clam(Ruditapes philippinarum) Culture System in Winter

试验结果表明:水中异养细菌为2.3×103-1.1×105cfu/m l,其变化趋势与温度变化一致;弧菌为5.0×103-6.6×103cfu/m l,其变化趋势与温度变化不一致,规律性不强。沉淀池泥中异养细菌为7.6×104-6.7×105cfu/g,弧菌为1.6×103-5.4×103cfu/g,反硝化细菌为2.5×102-3.2×104MPN/g,反硫化细菌为35-4.9×105MPN/g;温度高时,沉淀池泥中反硫化细菌占总异养菌比例最高,反硝化细菌次之,弧菌最小。从异养细菌的数量来看,沉淀池水质达到富营养化水平。因此,温度一旦升高,水中细菌会急剧增加,造成水质恶化,产生有毒的H2S、NO2-等物质,不利于菲律宾蛤仔的生长。

The trial results showed that the number of heterotrophic bacteria in the water varied from 2.3 × 10^3 to 1.1 × 10^5 （cfu/ml） depending on water temperature. The number of Vibrios ranged from 5.0 to 6.6 × 10^3 （ cfu/ ml） independing on water temperature. In sedimentary ponds, the heterotrophic bacteria varied from 7.6 × 10^4 to 6.7 × 10^5（cfu/g） in number, and the number of the Vibrios ranged from 1.6 × 10^3 to 5.5 × 10^3（cfu/g）. There was denitrification bacteria in the water at a range of 2.5 × 10^2 to 3.2 ×10^4 （MPN/g）. The number of desulphurizing bacteria ranged from 35 to 4.9 × 10^5（MPN/g）. At high temperature, the percentage of denitrifying bacterium in heterotrophic bacteria was the highest, followed by desulphurizing bacteria, then the Vibrio. The measure to control the number of bacteria should be taken to maintain the water quality for Ruditapes philippinarum growth in a hatchery.