John Armour - Department of Natural Resources and Mines
John Reghenzani - Terrain NRM led the project to 2013
About 90 percent of the Australian banana industry is located on Queensland's wet tropical coast, which borders the Great Barrier Reef (GBR). Loss of nitrogen (N) and phosphorus (P) fertilisers off-farm is considered a serious threat to GBR water quality. The main loss pathways include leaching of N through the soil profile and erosive losses of both N and P from the soil surface. In 1994, an industry survey found that average N and P fertiliser use were 520 kg and 68 kg per hectare per year, respectively (Daniells 1995). Research started in 1995 to determine the optimal rates of N application indicated that application rates could be reduced to 150-220 kg N/ha/year (a reduction of 58-71 percent), provided that attention was paid to method of application and timing, as well as general aspects of crop management (Armour and Daniells 2002). Leaching losses were very significant for higher N application rates (400 kg N/ha) but were not documented for lower application rates (100-300 kg N/ha).
This study identified the need to further research slow release N products to possibly further reduce leaching losses. Slow release N sources have been available commercially for some time now but their cost has been prohibitive. However, this could change if sufficient quantity was used with associated economies of scale, or if severe restrictions on use of soluble nutrients were imposed to protect aquatic ecosystems.
In 2007, an industry survey found substantial reductions in N application rates in the Tully valley with approximately 260 kg N/ha/year applied to plant crops and approximately 315 kg N/ha/year applied to ratoons (S. Lindsay pers. comm. 2010).
PROGRESS UPDATES for this project are summarised here
Field trials will be established at South Johnstone Research Station with pilot projects on banana farms in the Johnstone catchment to facilitate uptake of new techniques.
The Research Outcomes Report for RRRD049 is available for download from the Final Report page. This report should be cited as:
Armour, J., Mortimore, C., Pathania, N., Wiltshire, N., Daniells, J., Masters, B. and Reghenzani, J. (2013). Minimising off-farm movement of nitrogen in the north Queensland banana industry. Report to the Reef Rescue Research & Development Program. Reef and Rainforest Research Centre Limited, Cairns (32 pp.). ISBN: 978-1-925088-26-7.
The project results have been summarised at several Reef Rescue R&D forums, visit the Events page.
A feature article on Neil Wiltshire (Project Researcher) and an R&D article from John Reghenzani were released via Reef Rescue Water Quality R&D e-Newsletter in May 2012.
Anon (2012) Nitrogen trials continue as researchers study reef health. Tropical Banana News, July 2012, 9:2.
Daniells, J.W. (2012) Field event walks the talk on research. Australian Bananas 37: 7.
Daniells, J.W. (2012) Evaluation of slow release fertilisers in bananas. Handout – South Johnston Field Walk, 09 November 2012.
Reghenzani J., Daniells, J.W., Armour, J., Wiltshire, N. and Lindsay, S. (2012) Reef health nitrogen study bears fruit. Australian Bananas 36: 26.
Reghenzani J., Pathania, N., Wiltshire, N., Armour, J., Daniells, J.W., Mortimore, C. and Masters, B. (2013) Investigations on minimising off-farm movement of nitrogen in the north Queensland banana industry. Poster at 10th Australian Banana Industry Congress, Coolum, May/June 2013 [Congress program page 19]