Nextgen fertilisers for nutrient stewardship

Abstract

Fertiliser inefficiencies have enormous environmental costs, globally and locally. Our iconic Great Barrier Reef (GBR) is degrading and nutrient pollution is a main contributor. The GBR lagoon receives 6-times more nitrogen (N) than natural backgrounds, approximately 80,000 tonnes annually, and N-pollution reduction targets remain unmet. This long-standing problem is caused by fertilisers in broad-acre agriculture that rapidly dissolve and are subject to loss from soil. Authorities and stakeholders agree that the nutrient problem demands disruptive and transformative innovation. Enhanced efficiency fertilisers (e.g. plastic-coated urea) can reduce N losses but release patterns remain difficult to control. NextGen fertilisers take a new approach to better synchronise nutrient supply and crop demand. Capitalising on innovation in material science and process engineering, they form part of a future circular nutrient economy without pollution and waste. Our multi-disciplinary consortium of scientists, engineers and industry partners aims to break new ground and address the constraints that are costly for farmers and environment and prevent many tropical crops from reaching their yield potential. With proof-of-concept well established, next-generation fertilisers achieve superior nutrient-release properties by binding nutrients to sorber-matrices (biopolymers, biosorbers, bio-hydrogels, engineered natural clays). Engineered bio-/geo-sorbers form the basis of the NextGen platform that is complemented by re-purposed wastes, biodegradable coatings, crop-beneficial microbes and biostimulants, combined with processing technology. We showcase how agriculture profits from understanding of the crop-soil-microbe interface, and paired with engineering innovation, contributes to a 2nd Green Revolution that does not cost the earth.