围隔藻类水华演替过程中二甲基硫化物的含量动态

于2005年6月至7月，研究了海洋围隔不同藻类水华演替过程中二甲基硫化物的含量动态，并考察了相关环境参数对二甲基硫化物含量的影响。2个围隔实验组均出现未知藻水华-硅藻水华-甲藻水华的演替过程，这3次不同藻类水华分别对应了二甲基硫化物含量的3次高峰，表明藻类水华对二甲基硫化物含量有重要贡献。不同藻类水华的贡献有较大差异，甲藻水华的贡献最大，硅藻次之，未知藻类水华的贡献最小。实验结果还表明PO4^3-、NO2^-和NH4^＋主要通过影响藻类生长状态，进而影响DMSP和DMSO的含量；NO2^-和NH4^＋亦可能通过调节DMSP和DMSO在藻细胞内的生理功能，影响DMSP和DMSO的含量；PO4^3-、NO2^-和NH4^＋与DMS含量无显著相关。

Variations of the concentration of dimethyl sulfur compounds during three algal blooms in a mesocosm experiment

Variations of the concentration of dimethyl sulfur compounds(DMSCs)and the effects of environmental factors on the concentrations of DMSCs were investigated in a seawater mesocosm experiment from June to July 2005.Three large algal blooms,an unknown algal bloom,a diatom bloom,and a dinoflagellate bloom,respectively,were developed in the experimental enclosures.Three peak concentrations of DMSCs,corresponding to three algal blooms,indicated that algal blooms played an important role in the production of DMSCs.This study also showed that dinoflagellate bloom contributed the most to DMSCs,unknown algal bloom the least,and diatom bloom was intermediate.PO3-4,NO-2 and NH 4affected the productions of dimethylsulphoniopropionate(DMSP)and dimethylsulfoxide(DMSO)through the influence on the growth of algae,and NO-2 and NH 4might even affect the productions of DMSP and DMSO through the control of their physiological roles in the algal cell.However,no significant effects of PO3-4,NO-2 and NH 4on the production of dimethylsulfide(DMS)were evident.