The Relationship of Rheological Parameters and Erodibility of Soils

摘要

Aggregation, texture, organic matter content and permeability are the major factors controlling the soil's inherent susceptibility to erosion. Rheological measurements of concentrated suspensions can provide information on particle-particle interaction, the colloidal stability and structure of suspensions. Field samples from the experimental farm of Szent Istvan University (Hungary), and model samples of artificial complexes were investigated. Beside general laboratory analyses (soil organic matter content, CaCO_3 content, CEC), rheology was applied to investigate the microaggregate stability of the samples. The thixotropic low curve character and the evaluation of pseudoplastic flow curves indicated close relationships between strength and stability of the physical network and the composition of the particles. The stability and resilience of the aggregate structure was significantly higher in the presence of CaCO_3. Clay content and the amount and composition of organic matter also had an effect on attractive energy and separation distance between particles. Rheology proved to be a useful tool to investigate the influence of changing soil properties (such as soil organic matter content, CaCO_3 content, CEC) on aggregate stability. Separation of particles is a key process in erosion. We suggest that quantitative Theological parameters should be included in the methods used to predict credibility for erosion models.