Influence of maize cropping on the soil structure of two soils in the Waikato district, New Zealand

Abstract
Modification of soil physical properties resulting from the change of land lise from pasture to various periods of continuous maize cropping on two Waikato soils was investigated. Under present management practices on the two soils, maize cropping produced a deterioration of soil structure as indicated by changes in field properties, a slight increase in dry bulk density, a decrease in aggregate size, and a decrease in soil aggregate stability. On one soil an equilibrium in the state of soil structure was established after 3 years of maize cropping, and further cropping resulted in little modification of the physical properties. On the .;econd soil, however, the first two years of maize cropping were beneficial in terms of decreasing dry bulk density and increasing porosity, but these benefits were later lost with continued cropping.