多甲藻和微囊藻竞争利用不同形态磷增殖研究

为了探究不同藻竞争利用不同形态磷对浮游植物群落结构影响，分别以楯形多甲藻不等变种（Peridinium umbonatum var.inaequale）和铜绿微囊藻（Microcystis aeruginosa）进行PM4A板多磷源单培养实验，并向原位水样添加其两藻种进行5'-单磷酸腺苷（5'-AMP）和磷酸氢二钾（K₂HPO₄）增殖模拟实验.结果表明：不同的藻种对不同形态磷的竞争利用具有选择性，楯形多甲藻不等变种和铜绿微囊藻分别能够利用溶解性有机磷（DOP）35种和25种，两种藻能够较好的利用氨基酸和核苷酸.当以楯形多甲藻不等变种调控起始生物量占比（绿藻：甲藻：硅藻：蓝藻为38%：26%：20%：7%），无论以有机磷还是无机磷为磷源，甲藻的竞争优势明显，生物量占比达37.11%~50.19%；当以铜绿微囊藻调控起始生物量占比（绿藻：蓝藻：硅藻：甲藻为38%：29%：20%：4%），蓝藻竞争优势明显，生物量占比达52.25%~53.44%.在温度和光照等环境条件一定的情况下，磷源形态和藻类起始生物量结构共同影响浮游植物群落结构演替.

Proliferation of different forms of phosphorus in the competition of Peridinium umbonatum var.inaequale and Microcystis aeruginosa

To investigate the competitive utilization of different phosphorus species by different algal species and their influences on phytoplankton community structure, mono-culture experiments were performed firstly with Peridinium umbonatum var.inaequale and Microcystis aeruginosa in the PM4A plate at different phosphorus resources. Secondly, one species were added to natural seawater samples, separately, and performed mixed-culture experiments under 5'-AMP and K₂HPO₄ conditions. It was found that both species can make use of amino acids and nucleotides efficiently, and P. umbonatum var. inaequale and M. aeruginosa can, respectively, utilize 35 and 25 kinds of dissolved organic phosphates (DOP). These results suggest that dinoflagellate and cyanobacteria can take up DOP resources selectively. When P. umbonatum var.inaequale was used to regulate phytoplankton community composition, and chlorophyta:dinoflagellate:diatom:cyanobacteria were set to 38%:26%:20%:7%, dinoflagellate possessed competitive advantages regardless of the phosphorus resources and their percentages were 37.11%~50.19%. Once M. aeruginosa was added to natural seawater samples, and chlorophyta:dinoflagellate:diatom:cyanobacteria were set to 38%:29%:20%:4%, cyanobacteria had competitive advantages and their percentages were 52.25%~53.44%. Our data indicate that at the same temperature and light intensity, both phosphorus species and the proportion of initial phytoplankton biomass play important roles on regulating succession of the phytoplankton community.