3种湿地植物对锌的吸收分配及其与根表铁氧化物胶膜的关系

Relationship between Zinc Uptake and Accumulation of Wetland Plant and Iron Plaque on the Root Surface

在室内培养条件下,以灯心草、茭白和美人蕉3种湿地植物为材料,研究了湿地植物对锌的吸收分配能力与根表铁氧化物胶膜之间的关系。结果表明:(1)3种湿地植物积累锌的总量大小顺序为:茭白>美人蕉>灯心草,茭白积累锌的总量是灯心草的1.79倍;它们根表铁氧化物胶膜含量表现为灯心草>茭白>美人蕉,且其间存在显著差异(P<0.05)。(2)锌在湿地植物中分配比例表现为:根中锌量>地上部分锌量>根表铁氧化物胶膜上吸附锌量;锌主要积累在湿地植物根中,地上部分和根表铁氧化物胶膜上吸附的锌量无显著差异。(3)湿地植物根表铁氧化物胶膜上吸附锌的数量与湿地植物地下部分锌含量呈极显著正相关(r=0.983 5**),增加根表铁氧化物胶膜上锌的数量就能明显提高地下部分锌含量;每千克土壤加入1 g FeSO4后,3种湿地植物积累锌的总量平均增加了21%。可见,湿地植物根表铁氧化物胶膜对锌的吸附也是湿地植物固定或积累锌的重要途径之一。

The capacity of uptake and accumulation zinc of three wetland plants, and the effects of iron plaque on root surface of wetland plants on accumulation zinc were investigated in laboratory incubation. The results showed the following： （1）Total zinc amount accumulated by three wetland plants followed the order of Zizania aquatica〉Canna indica Linn. 〉Juncus effusus Linn. ,and total zinc amount of Zizania aquatica was 1.79 times higher than that of Juncus effusus Linn. ;The concentration of iron plaque on the root surface of three wetland plants was following the order： Juncus effusus Linn.〉Zizania aquatica Canna indica Linn. ,which were significant different （P〈0.05） among them. （2）The order of the distribu- tion Zn content of wetland plant was that root〉above ground organs〉iron plaque;Zinc was mainly dis- tributed and accumulated in root of wetland plants, and the significantly zinc accumulation difference between above ground organs and iron plaque on the root surface of wetland plants was not found. （3）The significant correlation between concentration of zinc absorbed by iron plaque on the root surface and below ground organs of wetland plants were found （r=0. 983 5＊＊ ） ,and concentration of zinc in below ground or- gans of wetland plants increased with increased zinc content absorbed by iron plaque on the root surface of wetland plants;The average total accumulation zinc of three wetland plants was increased to 21% ,when 1 g FeSO4· kg-1 soil was added. Zinc absorption by iron plaque on the root surface of wetlan（t plants was one of ways to accumulate zinc.