水体浊度对马来眼子菜和菹草生长的影响

Influence of water turbidity on growth of Potamogeton malaianus and Potamogeton cripus

研究了不同浊度(30、60和90 NTU)水体中,马来眼子菜及菹草的生长发育状况,并用水下饱和脉冲叶绿素荧光仪(Diving-PAM)测定其叶片荧光参数指标。结果表明,不同的浊度对马来眼子菜的叶片数及株高无显著影响,而对菹草的叶片数及株高生长速率有一定的影响。30 d胁迫下,浊度组马来眼子菜的最大光化学量子产量(maximum quantum yield,Fv/Fm)、光化学淬灭系数(photochemical quenching,q P)、非光化学淬灭系数(non-photochemical quenching,q N)、相对光合电子传递速率(electron transport rate,ETR)与对照组差异不显著(p>0.05),表明马来眼子菜对浑浊水体有较强的耐受能力;实验结束时,高浊度组(90 NTU)中,菹草Fv/Fm、q P、q N、ETR与对照组达到极显著差异(p<0.01),其余浊度组也相应受到影响,说明菹草的光系统II(PSII)受到破坏。该研究的成果可为沉水植物恢复研究与实践提供技术支撑。

In this study,the effects of three different turbidity gradients(30 NTU,60 NTU,90 NTU) were examined on the growth status of Potamogeton malaianus and Potamogeton cripus.Meanwhile,the fluorescence parameter index of their leaves were measured by a submersible,pulse amplitude modulated fluorometer DivingPAM.The results showed that turbidity significantly affected the number of leaves and the growth rate of Potamogeton cripus stems whereas no significant variation of Potamogeton malaianus was observed among different turbidity gradients.Furthermore,no significant differences of Fv/Fm,photochemical quenching(q P),non-photochemical quenching(q N) and electron transport rate(ETR) of malaianus were found between turbidity groups and control groups(p > 0.05) under stress in 10 days,which indicated that the Potamogeton malaianus had a strong turbidity resistance ability.Significant differences(p < 0.01) of values of maximum quantum yield(Fv/Fm),q P,q N and ETR were observed between the high-turbidity(90 NTU) groups and the control for cripus at the end of the experiment,while significant variations were also found between the other two turbidity groups,which showed that the photosystem II(PSII) of Potamogeton crispus was damaged.The conclusion of this study would provide technical support for the research and practice in submerged plant rehabilitation.