Simulation modelling to determine suitability of agricultural land

Land suitability assesses the potential of land for a specific land use. Traditionally, interactions between land characteristics and productivity are determined using qualitative methods. In contrast, a quantitative land evaluation uses a biophysical model to estimate these interactions. This paper presents a comparison between a qualitative and quantitative evaluation. l coverages of soil, climate and topography were compiled for approximately 2850 km2 of a dryland cereal cropping area in central Queensland, Australia. Model parameters that describe the soil were derived from soil survey data using surrogate methods. That is, no model calibration was used. The comparison of land suitability class and modelled yield showed that spatial modelling explained up to 80% of the variability in land suitability class. The results in this paper have provided confidence in the use of modelling techniques for land evaluation in Queensland, Australia.