University of Queensland Background
The natural nitrogen cycle has a number of avoidable losses through leaching and run-off of nitrate into waterways, and nitrous oxide emissions. Modern agriculture is driving the demand for higher levels of nitrogen than what is found in native soils, which is addressed by application of nitrogen fertilisers. However, frequent fertilizer application leads to enormous economic costs and environmental burdens associated with nutrient pollution and greenhouse gas emissions. Thus, strategies must be developed for improving nitrogen use efficiency. Clay-based soil amendments can help with the environmental sustainability, technical effectiveness of restoring degraded soils and enhancing crop yields.
Novel fertilizer amendments for agricultural applications designed through:
Engineering next-generation nano-clay materials with high exchange capacity to improve soil fertility, nutrient retention capacity, and the capacity to protect groundwater from cation leaching;
Developing efficient fertilizer formulations by achieving sustained release of nutrient from the nano-clay ‘absorber’ material;
Enhancing ammonia immobilisation capacity to minimise the emission of nitrogen (, )
The route of fabricating nano-clays is simple, scalable and cost-effective. The product generated is an ultra-fine powder that can be easily collected (right-hand image of )
Utilisation of nitrification inhibitors leads to improved nitrogen use efficiency i.e. higher crop yield for reduced N fertiliser application
Nano-clays are good candidates as nano-carriers for agricultural actives. For examples, nano-vermiculite and nano-bentonite shows 6 times higher loading of a nitrification inhibitor (DCD) than their raw clay counterparts.
Nano-vermiculite shows highly enhanced cation exchange capacity through exposed internal layers/edges. The ultra-small size of nano-clay leads to fast cation diffusion. Thus nano-vermiculite has applications as a soil improver.
The University of Queensland is seeking licensing, collaborative or investment partners to commercialise the technology.