天津滨海湿地不同植物矿质元素的分布及迁移特征分析

Distribution and Migration Characteristics of Mineral Elements in Different Coastal Plants of Tianjin

滨海湿地位于海陆交错地带,属于典型的生态脆弱区。探究滨海湿地植物中矿质元素的分布及迁移特征,有助于正确认识和理解滨海湿地生物地球化学循环这一关键过程。本文以天津滨海地区7种常见的湿地植物作为研究对象,研究P、K、Na、Ca、Mg、Al、Fe、Cu、Sr、Zn、Mn、Cr等12种矿质元素在植物不同器官中的分布与迁移特征。结果表明:Ca、Mg、Al、Fe、P在植物叶片和根系中的含量显著高于Sr、Zn、Mn、Cr、Cu、K、Na等矿质元素,且不同植物之间矿质元素含量的差异多与其抗盐和磷吸收的能力有关。所有植物中,大蓟对矿质元素的吸收能力弱,但转移能力强,狗尾草则趋势相反。其它如柽柳、刺儿菜、碱蓬、青蒿、盐地碱蓬等植物对多种矿质元素的吸收和转移能力均较高。相关分析表明12种元素组成的66对元素中,仅有14对元素密切相关,矿质元素之间的这种耦合与拮抗关系与植物自身代谢和不同器官的需求有关。主成分分析结果表明12种矿质元素根据功能可大致划分为三个组合,而碱蓬与盐地碱蓬在盐离子的吸收和转移功能上与其他植物明显不同。

Coastal wetland lies between marine and terrestrial ecosystems,which belongs to a typical ecological fragile area.Exploring the distribution and migration characteristics of mineral elements in coastal wetland plants is helpful to correctly understand the biogeochemical cycle process of coastal wetland.Taking seven typical wetland plants in Tianjin coastal area as the research object,this paper studies the distribution and migration characteristics of twelve mineral elements such as P,K,Na,Ca,Mg,Al,Fe,Cu,Sr,Zn,Mn,and Cr in different organs of plants.Results showed that the contents of Ca,Mg,Al,Fe and P in plant leaves and roots were significantly higher than those of Sr,Zn,Mn,Cr,Cu,K and Na,and the differences of mineral element contents among different plants are mostly related to their ability to resist salt and P absorption.Among all plants,Cirsium japonicum has a weak absorption ability,but strong transfer ability for mineral elements.While Setaria viridis has the opposite trend.Other plants such as Tamarix chinensis,Cirsium setosum,Suaeda glauca,Artemisia carvifolia,Suaeda salsa have high absorption and transfer capacity for many mineral elements.Correlation analysis showed that only 14 of the 66 pairs of elements related to each others closely.The coupling and antagonism phenomena between mineral elements were related to plant metabolism and the specific needs of different plant organs.Principal component analysis showed that 12 mineral elements could be divided into three groups according to their functions,and S.glauca and S.salsa are different from others in salt ion absorption and transfer functions.