Some influences of zero-tillage on the structure and stability of a fine-textured river levee soil.

Abstract

By means of physical and micromorphological analyses the difference in soil structure caused by ploughing and 5 years zero-tillage on a fine-textured fluviatile deposit was characterized. Although bigger pores were less stable and more affected by compaction, within each pore size class stability varied widely. Zero-tillage resulted in a denser and more homogeneous soil in which small aggregates disappeared and aggregate stability increased whereas pore continuity was not improved very much. Active pseudogleying was responsible for extensive bleaching in the zero-tillage profile, caused by a periodical lack of oxygen. The earthworm population increased markedly, but most earthworms were small. The number of large worm holes decreased sharply with depth, indicating a poor environment for the deep-burrowing worms which improve vertical water transport. Temporary pool formation occurred on part of the zero-tillage plots in the autumn and winter of the last few years, and after a heavy rainstorm in June 1975, when many worms died on the zero-tillage plots. (Abstract retrieved from CAB Abstracts by CABI’s permission)