英罗港红树植物群落不同演替阶段植物元素分布及其与土壤肥力的关系

根据广西英罗港红树植物群落的演替过程 ,研究了 5个主要演替阶段红树植物群落优势种地上部分的 7种元素 (N、P、K、Ca、Mg、Na、Cl)含量、群落元素积累量及其与土壤肥力的关系。结果表明 :1)红树植物不同器官元素含量大小为 :N、P、K均为花果 >叶 >枝 >皮 >干 ,Ca为皮 >枝、叶 >花果 >干 ,Mg为花果 >叶 >皮 >枝 >干 ,Na、Cl为叶、花果 >皮 >枝 >干 ;2 )同一器官中各元素含量均以Cl、Na最多 ,其次是N、Ca、K ,然后是Mg ,最少是P ;3)随着进展演替 ,红树植物群落优势种的N、P、K含量呈明显减少趋势 ,Ca、Na和Cl含量 (除木榄 (Bruguieragym norrhiza)外 )则呈现相反的趋势 ,而Mg含量缺乏明显的规律性 ;4) 7种元素在群落里的积累量大小顺序为红海榄(Rhizophorastylosa)群落 (4 2 82 .4kg·hm-2 ) >木榄群落 (2 96 4.2kg·hm-2 ) >秋茄 (Kandeliacandel)群落 (2 831.9kg·hm-2 ) >桐花树 (Aegicerascorniculaturn)群落 (134 2 .0kg·hm-2 ) >白骨壤 (Avicenniamarina)群落 (747.1kg·hm-2 ) ,其趋势是随着进展演替而增大 ;5 )不同演替阶段红树植物群落优势种的N、P、K、Ca 4种营养元素含量和群落元素总积累量与土壤肥力因素密切相关。可见 ,红树植物群落元素分布特征反映了红树植物对潮滩特殊生境的适应 ,而?

Investigation of Essential or Non-essential Character of Some Hardly Known Trace Elements for Plants

The concentration distribution of essential and non-essential micro-elements of the tissues of healthy organisms shows significant difference. This fact can be used for clarification of the biological role of hardly known trace elements, as well, proving the essential or non-essential character. In case of essential elements the concentration range is rather narrow, the distribution is normal. In case of non-essential elements the interval is wide, the concentration-distribution is log-normal. Measurements and mathematical calculations were carried out for determination of the concentrations and concentration-distributions of some micro-elements, trying to clarify the essentiality or non-essential character of the investigated elements from point of view of plant physiology. Based on the measurements for radish Li and Ni seem to be non-essential trace elements, however in case of Sr the distribution curve suggests an essential character, because the concentration range is not wide.