长江源区紫花针茅高寒草原优势植物化学元素含量特征

Characteristics Analysis of Element Contents in dominant species and Soil of Stipa purpurea steppes in the Source Region of Yangtze River

分析了长江源区紫花针茅草原的土壤和17种优势植物中15种元素的自然含量特征。植物中>1 000μg.g^(-1)的元素有Ca和Na,100～1 000μg.g^(-1)的元素有K、Mg、Mn、Fe、Li和Sr,10～100μg.g^(-1)的元素有Zn、Cu和Cr,<10μg.g^(-1)的元素有Ni、Co、Pb和Cd。土壤中各元素含量的顺序为Ca>Fe>Mn>Mg>K>Li>Na>Sr>Cr>Zn>Cu>Ni>Co>Cd>Pb。植物和土壤中元素含量特点是Ca>K型。植物对于土壤元素的吸收能力大小顺序是:Na>Sr>K>Zn>Mg>Ni>Pb>Cu>Mn>Ca>Li>Co>Cd>Fe>Cr,植物对于Na吸收系数达到13.228,其富集能力明显大于其余14种元素。元素之间K的累积与其他元素没有显著的相关关系;Na的累计也仅与Zn、Sr呈显著相关与其他元素无显著的相关关系,Pb和Na呈显著负相关。

It is analyzed that the contents of 15 elements of soil and 17 dominant plant species of Stipa purpurea steppes in the Source Region of Yangtze River in the study.the results show that:as to the average element contents of plant,Ca and Na were higher than 1000μg.g^(-1);K,Mg,Mn,Fe,Li and Sr ranged between 100 and l000μg.g^(-1);Zn, Cu and Cr ranged between 10 and 100μg.g^(-1);Ni,Co,Pb and Cd were less than 10μg.g^(-1).Element contents in soil were arranged in Ca>Fe>Mn>Mg>K>Li>Na>Sr>Cr>Zn>Cu>Ni>Co>Cd>Pb.The main character of the element contents was of the Ca>K type.The absorption coefficient of plant for soil elements are in order of Na>Sr>K>Zn>Mg>Ni>Pb>Cu>Mn>Ca>Li>Co>Cd>Fe>Cr.the accumulation index,the ratio of accumulation of nutrient elements in plant to that in soil,can reflect the relationship.Na have the highest accumulation coefficient 13.228.The accumulation of element K has no significant Correlations with the other elements,so does element Na except for the significant Correlations between Zn and Sr;Pb has significant negative correlation with Na.