根鞘是指在植物根系表面存在的由土壤颗粒与根表及根毛相互粘附、缠绕形成的土壤连续体,是植物对干旱逆境环境适应的一种生理机制.以扁穗冰草(Agropyron cristatum)为研究对象,对其根鞘土壤和周围环境土壤的理化性质和微生物数量进行了比较研究,以探求根鞘土的特性.结果表明:扁穗冰草根鞘土壤的含水量、pH、有机质、全氮、速效磷、速效钾和微生物数量都优于周围环境土,试验证明根鞘土具有保水、保肥的生态功能,同时是一个丰富的微生物库.
Rhizosheath is soil particles in the surface of plant root and by root hair mutual winding, which is a physiological adaptation mechanism to drought stress environment. The soil physicochemical proper- ties and microbe biomass between rhizosheath and surrounding soil were compared to explore the charac- teristic of rhizosheath. Results showed that both physicochemical properties and microbial biomass in the rhizosheath of Agropyron cristatum were better than that in the surrounding soil. The rhizosheath had the function of water and fertilizer conservation, and also was a potential repository of microbes.