Rheological properties of natural and disturbed structure samples of soddy-podzolic and agro soddy-podzolic soil

Abstract

The rheological properties of two profile`s horizons of soddy-podzolic and agro soddy-podzolic soil were studied by the amplitude sweep test on a rheometer MCR-302 (Anton Paar, Austria) on samples of natural structure (pastes) and disturbed structure (monoliths). Curves of the elasticity and viscosity modules determine the linear viscoelasticity range (LVE-range) of soil pastes and monoliths, the elastic modulus in linear viscoelasticity range as a characteristic of strength of structural bonds, the transition from viscoelastic to viscous behavior-the intersection of the elasticity and viscosity modules. It is established that the LVE-range of monolithic samples is more than paste samples, they are characterized by stronger structural bonds in the linear viscoelastic range; however, the destruction of structure in monolithic samples occurs at lower deformation values than in paste samples. The differentiation of the rheological parameter values of the upper part of profile of soddy-podzolic soil is caused by the large content of organic matter in the humus horizon and the facilitation of the soil texture in the eluvial horizon. The strength of structural bonds of the samples of the lower horizons of soddy-podzolic and agro soddy-podzolic soils differ insignificantly.

Keywords

• структура почвы
• реология
• метод амплитудной развертки
• реометр
• soil structure
• rheology
• amplitude sweep test
• rheometer