Cooperative Research Centre for developing Northern Australia (CRCNA) commissioned the project for assessment oftheland, water and climate of the Northern Territory for commercial production of cotton and grain crops. Cotton Research and Development Cooperation (CRDC) and Grains Research and Development Cooperation (GRDC) co-contributed in project design and financial allocations. The project implementation was led by the Northern Territory Government Department of Industry Tourism and Trade, and project collaborators included the Northern Territory Farmers Association Inc (NT Farmers), Department of Environment, Parks and Water Security (DEPWS) of the Northern Territory Government, Department of Agriculture and Fisheries (DAF) of the Queensland Government, Commonwealth Scientific and Industrial Research Organisation (CSIRO), University of Southern Queensland (USQ), and commercial stakeholders of the Northern Territory's plant-based industries. Specifically, the project aimed to identify potential crops, the timing and length of the potential cropping windows, and the impacts of climate and edaphic conditions on yield and quality. Where accessible, any historical data of previous cropping trials conducted in the Northern Territory was acquired. Field trials were established at Northern Territory Government's research farms and commercial properties. These data were used to determine the productivity of broadacre cropping systems by applying Agricultural Production Systems sIMulator (APSIM) - to investigate how a range of crop species will perform in terms of production and risk profile across the trial sites. Validation trials were conducted under rainfed and irrigated planting systems.
Validation trials included an intensive in-crop sampling and monitoring protocol to match simulated output to actual plant growth dynamics. This included soil sampling to at least 1.5 m with full soil water characteristics being determined. Above ground plant data collected in-crop included crop management records, full phenological monitoring, and at determined intervals leaf area, biomass, plant population and light interception, and crop yields.
The natural resource database determined the possibility of sowing crops during the breaks in the wet season - that allows the crops to best capture wet season rainfall and thus have sufficient soil moisture to carry a crop through to harvest. Soil type was found be a strong determinant of this strategy. The project findings suggest that the natural resource database to enable simulated productivity be measured on a regional scale to provide detailed indication of industry's potential to expand into commercial broadacre farming.
The APSIM modelled output for cotton and peanut provided an initial indication of the potential and extent of possible broadacre agriculture across the Northern Territory. The APSIM analysis was also trialled by adapting proven online tools (CropARM) as a resource to allow stakeholders to assess cropping options in the Northern Territory. Since the crop simulations allow for virtual cropping over numerous years the impact of the highly variable Northern Territory weather on year to year viability of cropping can be assessed. This will allow for economic analysis to be completed to understand the financial implications for investing in this form of agriculture. This information will help to direct future agricultural RD&E in the Territory. Further this will assist planners to understand the infrastructure required to support this potential cropping industry. To this end, the virtual cropping has highlighted some issues and knowledge gaps that will require further research to answer, hence overcoming a shortage of learned experience regarding broadacre cropping in the Northern Territory. Finally, in addition to the field trials and modelling, the project addressed the low local knowledge of farming by providing advice and back-up for multiple on-farm commercial trial plantings of both cotton and grains crops. These trials acted as assessment sites for crop simulations, learning sites for the farms concerned and as demonstration sites to extend cropping practice to other local producers.
Cotton Research and Development Corporation