浙江诸暨三角帆蚌养殖池塘浮游植物群落结构和理化环境

Phytoplankton community and abiotic environmental factors in commercial Hyriopsis cumingii ponds at Zhuji

2011年8月29日-9月1日采样分析了浙江省诸暨市枫桥镇10口三角帆蚌（晰riopsiscumingii）养殖池塘中的浮游植物种类组成、生物量和理化环境因子。结果显示，三角帆蚌养殖池塘内共观察到浮游植物51属（种），优势种为平裂藻、微囊藻、腔珠藻和栅藻；浮游植物生物量为0．71-8．01×10^8cell／L，71％～97％为蓝藻。池塘内的透明度（SD）平均值为33cm、溶氧（DO）为4～12mg／L、总氮（TN）为1．933～4．062mg／L、总磷（TP）为0．154～1．010mg／L、高锰酸钾指数（COD_mn）为6．49～10．06mg／L，说明三角帆蚌养殖池塘具有DO较高，SD、TN、TP、CODM_mn和TN／TP较低的特点。RDA分析显示水温是影响池塘中浮游植物常见种类生物量的主要环境因子，说明相近池塘的浮游植物群落接近。鉴于所调查的池塘内TN、TP、COD_mn和TN／TP较低，建议适当增加杂食性鱼类放养密度和配合饲料投喂量并降低鸭粪施肥量。

In this study, we investigated the species composition and biomass of phytoplankton and abiotic environmental factors in ten commercial Hyriopsis cumingii ponds located in Zhuji City, Zhejiang Province, from August 29 to September 1,2011. A total of 51 genus of phytoplankton were observed, and Merismopedia sp., Microcystis sp., Coelosphaerium sp. and Scenedesmus sp. were the dominant species during the investigation. The biomass of phytoplankton was 0.71 ×10^8cell/L, and blue-green algae account for 71 -97% of the phytoplankton biomass. Dissolved oxygen （4 -12 mg/L） was relatively high, while Secchi depth （33 cm）, total nitrogen （TN, 1.933 -4.062 mg/L）, total phosphorus （TP, 0. 154 -1.010 mg/L）, chemical oxygen demand （6.49 ×10.06 mg/L） and TN/TP were low in the ponds. According to results of this investigation, it is recommended that the stocking density of omnivorous fishes and input of formulated fish feed should be increased, while the amount of duck manure input should be reduced, in these commercial ponds.