Changes in Cropping Systems at the Boundaries of the Pastoral and Cropping Zones in Southern Australia.

Abstract

A history of cropping at the margins between arable and pastoral lands is examined. Assessment is made of the climatic factors that caused the abandonment of cropping. These criteria are then used to assess the likelihood that future cropping will persist along the present pastoral margins in different states of Australia. A minimum requirement is that the ratio of water use to evaporation in the growing season should exceed 0.3. An analysis of past climatic data should also be made to identify sequences of years when rainfall was both above and below average. Periods of above-average rainfall can lead to undue optimism for future cropping. Simple climatic models are required so that farmers can use them to predict the rainfall in the growing season and thereby make appropriate management decisions. Farming is a complex technical and financial business and farmers will need skills in monitoring, measuring and recording factors that influence their livelihood.