珠海地区凡纳滨对虾淡水养殖池浮游植物群落的演替

对珠海凡纳滨对虾淡水养殖池塘浮游植物及其理化因子进行了调查和分析．结果表明：调查中共检出浮游植物143种．优势种主要有林氏藻、螺旋鱼腥藻、小颤藻、微囊藻和点状平裂藻等．物种多样性指数在0．24～2．77之间．优势度与多样性指数呈显著的负相关．相关系数r=-0．984；而均匀度与多样性指数呈显著的正相关．相关系数r=0．967．养殖后期优势度不高。浮游植物的密度及化学因子的浓度到后期都有所上升．藻类密度的剧烈变化会引起氨氮和硫化氢含量的变化；藻类密度的波动滞后于无机氮的波动。群落演替具有突发性、时间短、速度快等特点。

Phytoplankton Community Succession of Freshwater Pool of Litopenaeus vannamei Bonne in Zhuhai Area

Investigations were conducted on the phytoplankton species and the physicochemical factors in the Penaeus vannarnei Bonne ponds in Doumen, Zhuhai City. The results showed that 143 species of the phytoplankton and the dominant species were Lyngbya sp. , Anabaena spiroides ,Oscillatoria tenuis ,Microcystis sp. ,Merisrnopedia punctata , etc. Its Shannon-Weaver index was 0. 24-2.77; the Shannon-Weaver index was negatively correlated to dominant degree, correlative coefficient r =-0. 984 and it was positively correlated to the well-distributed degree,r =0. 967,the dominant degree was not high in later period; The densities of the phytoplankton and the physicochemical factors rose in later period. Its content of ammonia nitrogen and H2 S would change with the change suddenly of density of the phytoplankton. Fluctuating of density of the phytoplankton lag inorganic nitrogen with the characteristics of sudden and quick occurrence in community succession.