富营养化导致了湖泊沉水植被消亡,是我国众多湖泊存在的普遍现象.在富营养化未能有效控制的前提下,采用人工措施重建沉水植被,已被水环境工作者普遍关注.然而,受水体温度、透明度、营养盐以及适宜的物种等限制,沉水植被的有效重建面临诸多困难.本研究着眼于温度对沉水植被重建的影响,设置了5、10、15、25、30、35℃6个温度处理,在人工气候箱培养条件下,对黑藻Hydrilla verticillata和马来眼子菜Potamogeton malaianus在5 h、10h、14h和7d处理后的蛋白质含量、过氧化物酶(POD)、超氧化物歧化酶(SOD)和过氧化氢酶(CAT)活性进行了测试.同时考察了实验前后植物生物量积累的情况,比较了不同温度胁迫下,两种植物生物量的净积累与抗氧化酶活性和可溶性蛋白含量的关系,试图为沉水植被的恢复提供理论依据和经验借鉴.结果表明,25℃是两种植物生物量净积累的最佳温度,此温度下,各种酶活性和可溶性蛋白未随处理时间的延长而显著变化.高于或低于25℃的处理,生物量净积累显著下降.并且,表现为短期胁迫5～14h内,各种酶活性和可溶性蛋白随处理时间的延长呈上升或下降的趋势,7 d长期胁迫后上述指标均低于25℃处理.结果表明,25℃外,其它处理均不同程度受到了温度的胁迫.短期胁迫,各处理的酶活性和可溶性蛋白表现了激烈的响应,以清除和维持植物体内活性氧的平衡和植物细胞较低的渗透势,保持植物正常的代谢活动.随着胁迫时间的延续,抗氧化酶系统受损,可溶性蛋白降低,植物正常的代谢紊乱,最终导致实验结束时,各处理植物生物量的积累存在较大差异.%Eutrophication results in the vanishing of submerged macrophytes in lakes, which are the very popular phenomenon in most lakes in China. Before the effective control of eutrophication, artificial reestablishment of submerged macrophytes has been frequently recognized by researchers in the field of water environment. However, difficulties are always encountered during the rees-tablishment of submerged macrophytes due to the limits in water temperature, transparency, nutrients and suitable plant species. In order to investigate the effect of temperature on the submerged macrophytes, Hydrilla verticillata and Potamogeton malaianus were cultured in the environmental controlled growth chambers with a different temperatures of 5, 10, 15, 25, 30 and 35 ℃, and biomass accumulation, protein content, POD, SOD and CAT activities were measured at 5, 10, 14 hours and 7 days after the treatments. The results showed that the optimal temperature for maximum biomass accumulation was 25, and under this particular temperature all the enzyme activities and soluble protein contents did not change much within the treatment period, while temperature higher or lower than this particular temperature, the biomass accumulation decreased remarkably, and furthermore enzyme activities and soluble protein contents also increased or decreased with the time in the short term treatment (5～14 h), which might be the defense reactions to scavenge ROS and maintain ROS balance and relative lower osmotic in the plants, however, at 7 days all the parameters measured were decreased, which might be results of the damage of antioxidative enzyme system and metabolism, thus leading to the decreas-ing of biomass accumulation.
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