Soil organic matter changes and crops responses to fertiliser under conservation cropping systems in the semi-arid tropics of North Queensland, Australia

Abstract

Soil organic matter changes due to cropping in the semi-arid tropics were studied in an area with cropping potential. Soil organic carbon and total nitrogen (N) decreased after clearing and tillage, but decline was less where pasture-crop rotations were used. Crop N removal was high and exceeded the recommended fertiliser N rate. These results suggest that if cropping expansion occurs, careful management the is necessary for long-term productivity and land resource protection.