Abstract: Bioaccumulation of nutritive elements, N、P、K、S、 Fe was studies in the paper.The storage and distribution of these 5 elements in soil and different lant species were analyzed of the Leymus chinesis steppe in Inner Mongolia.The results showed that amount of N storage was the highest both in soil and species.Accumulation of those elements showed that K was found higher in roots than in above-ground part, which is benefit for returns.Species and biomass also affected on the distribution of the elements.In soil, the amount of element resorre was in order as: N > K> S> Fe > P.

Key words: Bioaccumulation, Nutritive element, Temperatre steppe, Isohumisol

摘要： 本文研究了内蒙古锡林河流域暗厚简育干润均腐土(J_2、4、5)氮、磷、钾、硫、铁等不同营养元素的生物积累。结果表明:植物地上部生物积累的特点为:氮累积累量高达3.43克·米^-2,钾素为2.916克·米^-2。不同植物在生物积累中的作用,除受元素含量高低的影响外,还取决于该植物的生物量。生长在暗厚简育干润均腐土上的羊草,由于生物量高,所以在生物积累中所占例亦最高,一般都高于50%。植物地下部的生物积累亦属氮素最高,可达16.53克·米^-2。地下部生物量沿剖面分布为上大下小呈“丁”字型,其营养元素的生物积累在上部土层高于下部土层。土壤对五种营养元素生物积累的顺序为:N>K>S>Fe>P。在地上部和地下部的分配中除钾素外,其余四种元素在地下部的生物积累都占绝大部分,这一特点的存在,为保持土壤肥力和草原的持续利用起着重要作用。为维持草原生态系统营养元素的平衡,应对放牧地、割草地补充相应数量的氮、磷、钾等营养元素。

关键词: 生物积累, 营养元素, 温带草原, 均腐土