Norwegian Journal of Agricultural Sciences : effects of slurry application on the microstructure of the surface layers of soils from northern Norway

Abstract

Thin sections, prepared from undisturbed soil samples, were used to investigate the influence of surface application of fresh and aerated cattle slurry on the microstructure and composition of the topsoil. Virgin and cultivated silty and sandy soils from northern Norway were studied.Both types of slurry were present as a fairly continuous layer on the top of the soil surface, but it was found that neither fresh nor aerated slurry penetrated into the soil. The application of liquid slurry produced an increased compactness of the microstructure of the surface of the virgin silty soil. In the cultivated silty soil and virgin and cultivated sandy soils, the treatment did not affect the fabric of the soil surface. This explains the observed decrease in the infiltration rate after surface application of liquid slurry. In both soils cultivation led to a marked modification of the microstructure: in the silty soils the microstructure of the cultivated soil was less developed and more compact than that of the virgin soil; the cultivated sandy soil had a much lower c/f ratio than the virgin soil.