西南地区水耕人为土诊断层土壤特性及SEM特征

对我国西南地区代表性水耕人为土诊断层土壤特性进行研究,并采用扫描电镜(SEM)进行土壤微形态研究,结果表明:不同母质和发育程度的水耕人为土,在土壤特性及在剖面上的变化特征都有明显差别.通过SEM观察研究表明:粗、细颗粒物质形态与矿物组成密切相关,如以薄片状、针条状等细粒物质为主的土壤,在水耕条件和外力作用下,易于定向、粘结聚合而引起土壤压实和板结.水耕人为土的微团聚体含量少而分散,对肥力的贡献有限.长期培肥的水耕人为土能够形成丰富的各类微孔隙和微结构类型,是调节土壤水、热、气和养分状况的主要机制.

Soil Properties and SEM Features of Diagnostic Horizon of Stagnic Anthrosols in Southwestern,China

The soil properties and ultra microstructures of diagnostic horizon of typical Stagnic Anthrosols in southwestern China were studied by scanning electron microscopy(SEM)method.The results indicated that soil properties and variability of profiles showed obvious differences among Stagnic Anthrosols that developed from different parent materials and developed degrees.The SEM observation revealed that the morphologies of coarBe and fine material were correlated to mineral composing closely,e.g.soils which were predominated by fine material of lameHiform and needle strip form were prone to compaction and hardened owing to the effect of orientation and polymerization under anthrostagnic condition and external forces.As the:micro-aggregation of Stagnic Anthmsols was few and diffused,its contribution to fertility was limited.While,a mass of various micro-pores and micmstructures were formed in long-term fertility betterment soils,and this Was the main mechanism to adjust water,heat,air and nutrient harmoniously in Stagnie Anthrosols.