虾蟹混养池塘浮游植物群落结构的变化特征

为摸清锯缘青蟹(Scylla serrata)与斑节对虾(Penaeus monodon)混养池塘浮游植物种群结构的变化特征,于2018年3-11月对广州市番禺区十六涌3个养殖池塘中的浮游植物开展了逐月调查,并通过冗余分析(RDA)探讨了浮游植物与环境因子的相关性。结果表明,养殖池塘中共鉴定出浮游植物29种,主要由硅藻、蓝藻、甲藻、绿藻和裸藻5大门类组成,其中硅藻种类最多(19种),占浮游植物种类数的65.5%;其次是蓝藻,共5种,占浮游植物种类数17.2%;甲藻3种,绿藻和裸藻各1种。共出现优势种16种,主要为直舟形藻(Navicula directa)、奇异菱形藻(Nitzschia paradoxa)、柔弱菱形藻(Nitzschia delicatissima)、尖布纹藻(Gyrosigma acuminatum)、大角角藻(Ceratium macroceros)和小颤藻(Oscillatoria tenuis)等。浮游植物细胞密度介于2.56×103~189.2×103个·m-3,Shannon-Weaver多样性指数介于0.468~2.597。浮游植物与环境因子相关性RDA结果表明,营养盐、盐度和pH是影响养殖塘浮游植物种群结构的主要环境因子。

Variation characteristics of phytoplankton community in polyculture ponds of Scylla serrata and Penaeus monodon

To understand the variation characteristics of phytoplankton population structure in the polyculture ponds of Scylla serrata and Penaeus monodon,we have conducted a monthly survey on the phytoplankton in three cultured ponds in Panyu District,Guangzhou from March to November 2018,and discussed the relationship between phytoplankton and environment factors based on redundancy analysis(RDA).The results show that a total of 29 species in five Phyla were identified,among which the most abundant group was Bacillariophyta,with 19 species accounting for 65.5%of the total species,followed by Cyanophyta(5 species,17.2%),Pyrrophyta(3 species),Chlorophyta(1 species)and Euglenophyta(1 species).Navicula directa,Nitzschia delicatissima,Gyrosigma acuminatum,Ceratium macroceros and Oscillatoria tenuis were the dominant species during the investigation.The abundance of phytoplankton cells varied from 2.56×103 to 189.2×103 cells·m?3.The variation of Shannon-Weaver diversity index ranged from 0.468 to 2.597.RDA reveals that nutrients,salinity and pH were the primary environmental factors influencing phytoplankton community.