摘要
【目的】研究盐度对球形棕囊藻(Phaeocystis globosa)光合活性的影响,进一步认识该物种时空分布格局的形成,为赤潮预警预报提供基础数据。【方法】将2.00×10^(4)mL^(-1)的单细胞球形棕囊藻分别在0、5、10、15、20、25、30、35和40等9个盐度下培养7 d,每天用流式计数法测定细胞丰度,用叶绿素荧光仪测定叶绿素荧光参数。【结果与结论】球形棕囊藻最适生长盐度为35,藻细胞在盐度25~40下生长良好,在盐度15~20下生长缓慢,在盐度为0时全部死亡,叶绿素a荧光值下降为0,在盐度10和5时停止生长并出现大量死亡。藻细胞光合系统Ⅱ在15~40盐度条件下功能正常;0~10盐度条件下,遭受不同程度的破坏,其中0盐度条件下1 d内遭受不可逆破坏,最大光能转化效率(F_(v)/F_(m))、实际光能转化效率(Φ_(PSⅡ))、初始斜率(α)、最大相对电子传递速率(rETR_(max))、半饱和照度(I_(k))、非光化学淬灭系数(NPQ)和光化学淬灭系数(qP)急剧下降,并不可恢复;5盐度组也在1 d内遭受严重损伤,存活藻细胞在4 d后光合系统部分恢复,其Fv/Fm、Φ_(PSⅡ)、α、NPQ和qP值迅速降低后逐渐上升,但多未恢复到正常水平;10盐度条件下4 d后胁迫效应方出现,其F_(v)/F_(m)、Φ_(PSⅡ)、α值在4 d后下降,7 d时显著低于15~40盐度处理(P<0.05)。为修复受损的光合系统,细胞对强光的耐受能力提高,7 d时5与10盐度组的rETR_(max)和I_(k)值显著高于其他各组(P<0.05)
【Objective】To study the effects of salinity on the photosynthetic activity of Phaeocystis globosa,further understand the formation of the spatial and temporal distribution pattern of this species,and provide basic data for red tide early warning and prediction.【Method】The solitary cells of P.globosa were cultured in culture media at the salinities of 0,5,10,15,20,25,30,35 and 40 respectively,for 7 days with the initial density of 2.00×10^(4)mL^(-1).During the experiments,the cell density and the parameters of chlorophyll fluorescence were determined respectively by flow cytometer and chlorophyll fluorometer.【Result and Conclusion】The optimal salinity and suboptimal salinity for the growth of P.globosa solitary cells were 35 and 25‒40 respectively.And cells grew slowly at salinity of 15‒20.Cells did not survive at salinity of 0 and the fluorescence value of chlorophyll a in this treatment was zero.P.globosa stopped growth at the salinities of 10 and 5,and most of P.globosa cells died at these salinity treatments.The function of photosynthetic system Ⅱ in P.globosa was normal at the salinities of 15―40 but was destroyed at varying degrees at the salinities of 0‒10.Photosynthetic system of cells was irreversibly damaged within one day at the salinity of 0,with irreversible decrease of F_(v)/F_(m),Φ_(PSⅡ),α,NPQ and qP.Photosynthetic system of P.globosa was also destroyed within one day at the salinity of 5,with rapid decrease of F_(v)/F_(m),Φ_(PSⅡ),alpha,NPQ and qP values,but these indexes partly recovered except for qP after day 4,indicating that the function of photosynthetic system in surviving cells at the salinity of 5 could not recover back up to normal level at the end of experiment.The stress of 10 salinity on P.globosa only appeared after day 4,with the decrease of Fv/Fm,Φ_(PSⅡ) and alpha values,and the values of these parameters were significantly lower than that in 15‒40 salinity treatments at day 7(P<0.05).rETRmax and Ik were significantly higher at the salinity of 5 and
作者
韦福佳
陆家昌
赖俊翔
李杰
庄军莲
张萍
李锐龙
WEI Fu-jia;LU Jia-chang;LAI Jun-xiang;LI Jie;ZHUANG Jun-lian;ZHANG Ping;LI Rui-long(School of Resources,Environment and Materials,Guangxi University,Nanning 530004,China;Guangxi Beibu Gulf Marine Research Center/Guangxi Key Laboratory of Marine Environmental Science,Guangxi Academy of Sciences,Nanning 530007,China)
出处
《广东海洋大学学报》
CAS
CSCD
北大核心
2023年第1期17-24,共8页
Journal of Guangdong Ocean University
基金
广西创新驱动发展专项(AA17202020)。
关键词
球形棕囊藻
盐度
生长
叶绿素荧光参数
光合活性
光合系统
Phaeocystis globosa
salinity
growth
chlorophyll fluorescence parameters
photosynthetic activity
photosynthetical system
