漳江流域沿岸植物叶片中Si元素含量的变化

Changes of Si concentration in leaves of plants along the Zhangjiang River Watershed,southeastern China.

该文研究了漳江流域沿岸48种植物成熟叶片中Si元素含量及其随环境因子和在不同植物类群中的变化.结果表明,这些植物叶片平均Si含量为1.23%;不同植物叶片Si含量差异显著,含量最高的是笔管草,达5.88%;最低的是桃金娘,仅0.02%.48种植物中的17种是Si积累者,叶片Si平均含量为2.53%;31种是非积累者,叶片中Si平均含量为0.28%.从植物所属科来看,含Si量较高的主要有禾本科、木贼科、紫萁科、凤尾蕨科、鸭跖草科和桑科植物.研究还发现从上游到下游,土壤Si含量随土壤粘粒含量和含水量的升高而增加.马缨丹和鸭跖草叶片Si含量与对应土壤的有效Si含量呈正相关,桐花树和秋茄叶片Si含量与对应土壤的盐度呈正相关.

The authors determined the Si concentration of mature leaves from 48 plant species along the Zhangjiang River Watershed,Fujian Province,and then investigated its relation to soil traits and its phenogenetic variations in different taxonomic groups.The results showed that the Si concentration varied significantly within different plant species,and the average value was 1.23%.Among these plants,Hippochaete debile beared the highest content as up to 5.88%,while Rhodomyrtus tomentosa was the lowest,only 0.02%.In terms of plant family,the plants of Graminae,Equisetaceae,Osmundaceae,Pteridaceae,Commelinaceae and Moraceae were rich in Si,with 17 species could be identified as Si accumulators, which shared the average Si content of 2.53%,while the other 31 species were non-accumulators since the average Si content was only 0.28%.The authors also noticed that water and clay content of soil increased along the upstream of Zhangjiang River to the downstream,which resulted in the increase of Si content in the soil accordingly.The Si concentrations of Lantana camara and Commelina communis were positively related to the effective Si content in the soil,while that of Aegiceras corniculatum and Kandelia obovata had positive relationships with the salinity of soil.