A/Prof. Greg Hancock¹

¹The University Of Newcastle, Callaghan, Australia

Long-term soil data sets reporting soil properties for many parts of the world are limited particularly for the monsoonal tropics. We assess soil organic carbon along two hillslope transects in the tropical monsoonal north of Australia over a 14 year period (2002 – 2015). The study catchment is largely undisturbed by European agriculture or management practices. Wildfire occurs every 2nd year on average removing all vegetation. Field data demonstrates that soil organic carbon has remained stable despite regular fire occurrence. Vegetation (above ground biomass) significantly contributed to SOC. The spatial pattern of biomass was stable despite the regular fire – hence the stability of soil organic carbon. Soil organic carbon was also related to erosion and deposition patterns. Annual rainfall total also influenced soil organic carbon with higher annual rainfall increasing soil organic carbon for that year. The landscape has spatially stable vegetation, stable soil organic carbon and is resilient to fire.