INFLUENCE OF DIFFERENT NITROGEN AND PHOSPHORUS CONCENTRATIONS ON GROWTH,PHOTOSYNTHESIS AND MICROCYSTIN PRODUCTION OF MICROCYSTIS AERUGINOSA

摘要: Heavy blooms frequently occurred in eutrophicated water body and Microcystis is the main algae involved blooms.Microcystis produces a family of related cyclic hepatopeptides(microcystins,MC).These toxins are severely hepatotoxic.In this paper,a strain aeruginosa was isolated from cyanobacterial bloom east lake effects ammonium orthophosphate on its growth,chlorophyll-a(Chl.a) fluorescence microcystins(MC) contents investigated.Two experiment groups were tested,with variable ammonium(0—219.6mg/L),orthophosphate concentration fixed at 4.5mg/L,or with orthophosphate(0—110.7mg/L),ammonium 50mg/L.The results showed that,when fixed,ammonium had obvious influence growth M.aeruginosa.The content Chl.a evidently higher as concentrations ranged 1.83 to 18.3mg/L than those other concentrations.The overall MC including MC-LR MC-RR reached maximum 1.83mg/L while much 0.61 18.3mg/L.In addition,F_V both tended increase increased 0 1.83mg/L,higher restrained growth,physiology production aeruginosa.In another group increasing concentrations,the represented decreasing tendency opposite highly correlated F_V/F_m(P0.01,r=0.97).MC obviously below 0.56mg/L concentrations.It demonstrated by statistical analysis closely F_V/F_m(P0.01,r=0.967)