摘要
生长在土壤中的植物,其根系与土壤接触界面间的养分状况直接反映了两者的需求关系。了解这一微区的养分状况,对探讨养分从土壤向根系转移的机理和有效利用都具有重要意义,有关这方面的研究七十年代以来逐渐引起了重视。
The present article deals with the determination of potassium content in soil of rhizosphere in situ by the potassium selective micro-electrode.It was found that the equilibrium potential was established within 3 minutes in the soils with higher moisture content.While under lower moisture content,it was delayed up to 5 minutes.Similarly,the equilibrium in the soil with higher K^(+)concentration was established more quickly than that in soil with lower K^(+)concentration.Forty samples collected from yellow cultivated loessial soil,white bleaching paddy soil and sandy soil with different K^(+)content had been studied.The results showed that good correlation was found between the K^(+)concentration determined by the electrode method and the concentration of water-soluble K^(+)determined by the flame photometric method(r=0.931).Generally speaking,the electrode method may be a useful method for estimation of K^(+)concentration in situ.Electrode method has been used to estimate the change of K^(+)concentration in the soils with a distance of 1 mm,3 mm and more than 5 mm from root surface during the flowering and bolling stage of cotton and tillering stage of barley.In the.experiment,it was found that Kions tended to be accumulated in the soil of a thickness of 1—2 mm on the root surface.
作者
许曼丽
刘芷宇
Xu Man-li;Liu Zhi-yu(Institute of Soil Science,Academia Sinica Nanjing)
出处
《土壤学报》
1982年第4期367-374,共8页
Acta Pedologica Sinica
