高位虾池养殖过程浮游植物群落的演替

Succession of phytoplankton community in exalted shrimp ponds during culture process

通过对湛江东海岛北寮村和庵里村各2个高位虾池养殖过程的浮游植物演替和主要理化因子进行调查,研究浮游植物群落的演替过程对高位虾池的健康养殖的影响。结果表明:4池共检出浮游植物7门76属140种;对虾生长正常的北寮高位虾池演替优势种主要有螺旋环沟藻、椭圆扁胞藻、海链藻、湖泊束球藻密胞变种、裸甲藻、卵囊藻、微囊藻、锥形斯克里普藻、色球藻和尖尾蓝隐藻等,而对虾发病的庵里高位虾池演替优势种主要有铜绿微囊藻、柔弱布纹藻、咖啡形双眉藻、小席藻、卷曲鱼腥藻、水生集胞藻、衣藻、尖尾蓝隐藻和螺旋环沟藻等,北寮正常虾池浮游植物种类(包括优势种)较对虾发病的庵里虾池多而复杂;对虾生长正常池优势种的演替快而门类交替,而对虾发病池呈现硅藻到蓝藻优势的演替;对虾生长正常池浮游植物密度随养殖过程延伸呈上升态势,而对虾发病池浮游植物密度初期增加病害后下降;养殖过程浮游植物密度与主要理化因子的相关关系不显著;对虾生长正常的北寮高位池多样性指数与均匀度高于对虾发病的庵里高位池,而优势度却较低。水体理化因子变化平缓,浮游植物有较高的多样性指数和均匀度、较低的优势度对于稳定虾池养殖水环境有重要作用。

An investigation was made on the succession of phytoplankton community and the main physical and chemical factors of water body in exalted shrimp ponds in Beiliao and Anli villages of Donghai Island,Zhanjiang during culture process,with the influence of the succession on the culture process analyzed.A total of 140 species of phytoplankton belonging to 76 genera and 7 phyla were identified.The dominant species in the two ponds with normal shrimp growth in Beiliao village were Gyrodinium spirale,Platymonas elliptica,Thalassiosira sp.2,Gomphosphaeria lacustris var.compacta,Gymnodinium sp.1,Oocystis sp.,Microcystis sp.,Scrippsiella trochoidea,Chroococcus sp.,and Chroomonas acuta,while those in the two ponds with shrimp disease occurrence in the process of culture in Anli village were Microcystis aeruginosa,Gyrosigma tenuissimum,Amphora coffeaeformis,Phormidium tenue,Anabaena circinlis,Synechocydtis aquetilis,Chlamydomonas sp.2,Chroomonas acuta,and Gyrodinium spirale.The phytoplankton species,including dominant ones,were more abundant and complex in normal ponds than in disease-affected ponds.In normal ponds,the dominant species succeeded rapidly and alternated in phyla,while in disease-affected ponds,only Bacillariophyta species were replaced by Cyanophyta species during the succession.The phytoplankton cell density increased during the culture process in normal ponds,but decreased after a temporary increase at early culture stage in disease-affected ponds.No significant relationships were observed between the phytoplankton cell density and the main physical and chemical factors in the ponds during culture process.The diversity and evenness of phytoplankton species were higher in the normal ponds in Beiliao than in the disease-affected ponds in Anli,while the dominance degree of species was in reverse.The mild variability of water body＇s physical and chemical factors as well as the high diversity and evenness but low dominance degree of phytoplankton species played important roles in keeping aquatic environment steady and healthy during the culture process in exalted shrimp pond.