养虾污水对九龙江南溪下游微微型浮游生物群落的影响

Influence of shrimp farming sewage on the picoplankton in the lower reaches of Nanxi in Jiulong River

摘要: 2015年4月28日和7月12日在养虾密集区九龙江南溪下游河段设置的12个站点进行了水样采集，利用荧光显微方法，对12个站点的微微型浮游植物，异养细菌以及该河段的COD进行了研究和比较.结果表明在九龙江南溪下游，4月微微型浮游植物丰度、异养细菌丰度以及该河段的COD含量显著高于7月；九龙江南溪下游微微型浮游植物丰度、异养细菌丰度与该河段的COD含量呈现显著正相关，微微型浮游植物丰度与异养细菌丰度呈现显著正相关.表明随着养虾污水排放的增加，水中COD含量增加，导致异养细菌丰度增加.

Abstract: Abundance of autotrophic picoplankton（APP）， heterotrophic picoplankton （heterotrophic bacteria，BACT，0.2～2.0 μm） and the COD concentration were investigated in April 28 and July 12， 2015 at 12 stations in the lower reaches of Nanxi branch of Jiulong River. Higher abundance of autotrophic picoplankton， heterotrophic bacteria and the concentration of COD was detected in April than in July. Abundance of autotrophic picoplankton and heterotrophic bacteria was significant positively correlated with COD. Abundance of autotrophic picoplankton was significant positively correlated with abundance of heterotrophic bacteria. Results reveal that the discharge of shrimp sewage has raised the trophic status of water and increased COD concentration and the number of heterotrophic bacteria．