酸雨与稀土镧对大豆幼苗光合光反应复合影响的时间效应研究

采用水培法研究酸雨（AR）与稀土镧（La）对大豆幼苗叶片光合光反应复合影响的时间效应,旨在探究复合污染因子对植物自修复过程的影响。结果表明,较之不同pH值AR（pH3.0、4.0）和不同剂量La（60、300mg·L-1）的单一作用,复合处理对大豆幼苗光合光反应活性抑制程度较大,延缓各参数恢复进程（恢复拐点滞后）,恢复程度较小,明显影响了植物的自修复能力。净光合速率Pn与各光合参数相关性分析结果显示：复合处理组的植物在修复过程中,Pn变化主要受Chl、Hill反应活性的影响,Mg2＋-ATPase活性对Pn的制约最小,且随着时间的推移,AR与La复合处理组各光合参数的恢复进程不同步,自修复能力受胁迫强度和胁迫方式的影响。

Time-effects of Combined Treatments of Simulated Acid Rain and Lanthanum on Photosynthesis of Soybean Seedlings

Time-effects of combined treatment of simulated acid rain（AR） and Lanthanum（La） on photosynthesis in soybean seedling were investigated under hydroponic conditions in order to explore the combined effects on the recovery process of plant.The results indicated that the degree of inhibition on photosynthetic parameters in seedlings with combined treatments was higher than that treated with the single AR（pH3.0, 4.0）or La（60, 300 mg·L-1）. Compared with the single treatment, the combined treatment delayed the recovery process of the parameters（turning points of recovery were lagged）and the recovery degree was smaller,showing that the self-repairing ability of soybean seedlings was significantly affected. The correlation analysis between Pn and other photosynthetic parameters indicated that changes of Pn were mainly influenced by changes of Chl and Hill reaction activity, but not obviously affected by the change of Mg2＋-ATPase activity in seedlings under combined treatment. The results indicated that the self-repairing of each photosynthetic parameter was unsynchronized, and the self-repairing ability was related with stress intensity and stress mode.