VALIDATING THE 'SIX EASY STEPS' NUTRIENT MANAGEMENT GUIDELINES IN THE JOHNSTONE CATCHMENT

摘要

Nutrient inputs for sugarcane production in Australia have historically been based in simple generalised fertiliser recommendations. Recently these have been modified into sets of soil-specific nutrient management guidelines for use at district level. These modifications were achieved through the use of a 'systems-based' framework that recognises soils and soil properties as fundamental to a sound scientific approach to nutrient management. The SIX EASY STEPS program was introduced to deliver this approach and the modified nutrient management guidelines to the Australian sugar industry. This paper reports on the development of the SIX EASY STEPS guidelines for the Johnstone Catchment in particular. It also presents the results of field evaluations (participative replicated demonstration strip trials) that were established to validate this approach to nutrient management and to compare the SIX EASY STEPS inputs to usual grower nutrient input strategies in the wet tropical environments of north Queensland. The results of the field investigations conducted over two successive ratoon crops, indicate that the SIX EASY STEPS options have generally produced comparable yields to those obtained from the usual practices. Maintenance of yield, despite mostly lower nutrient inputs, is an important outcome, as it ensures that profitable cane production can be achieved in combination with environmental awareness. Calculated partial net returns indicate that appropriate nutrient management will potentially be of benefit to the industry as a whole (growers and millers).