Biochar-compost composites for supporting site-specific soil agro-ecosystem functions and climate change mitigation

Due to the intensified agricultural practices and climate change soils are rapidly degrading worldwide, becoming nutrient deficient. With the rising price of the commercial fertilizers, we need to create solutions to provide soils with sufficient amount of nutrients to sustain soil fertility. In sustainable agricultural practices, recycling nutrients from waste resources into valuable fertilizers is. The main objective of AgroComposit is to create a cost-effective, climate-smart composite fertiliser through co-composting locally available waste sources and by products (e.g. seaweed, aquaculture waste streams, sewage sludge, organic fraction of municipal solid waste) with biochar. The biochar-compost composites will effectively improve low-quality soils and their productivity by enhancing nutrient availability, water use efficiency under drought stress, carbon sequestration, and improving biodiversity. Reduction in emissions of greenhouse gases will be an additional benefit. The EJP project AgroComposit builds on recent advances in co-composting with biochar and aims to investigate gaps in the scientific literature. In AgriComposit, as a consortium, we will: 1) design, produce and characterize novel biochar-compost composite fertilizers 2) test the fertilizer value of the composites from laboratory to field in a scale-up technology development 3) develop a database to match certain biochars, organic wastes and low-quality soils and cropping systems to ease the design of site-specific soil improvement technologies 4) apply Life Cycle Assessment, cost efficiency assessment and environmental risk assessment to evaluate the efficiency of the technologies and their potential drawbacks, and 5) create venues for implementing the new fertilizer technologies in agricultural applications. The project will address five of the UN SDGs, making it a crucial step towards sustainable agricultural practices.

In a climate-smart agriculture, it is necessary to recycle waste resources, however currently still only a small proportion of all organic wastes is recycled back into the soil. The main goal of the Agrocomposit project is to develop site-specific soil improvement technologies applying composite soil amendments produced from region-specific organic wastes and by-products. The composites will be suitable for the effective improvement of low-quality soils and their productivity focusing on the enhancement of nutrient availability, water use efficiency under drought stress, carbon sequestration and improving biodiversity. The project will primarily focus on co-composting biochar and various organic wastes, such as kelp, aquaculture waste streams, sewage sludge, and the organic fraction of municipal solid waste, which are produced in large quantities in the participant countries but are not effectively utilized. The European consortium will: 1) produce and characterize biochar-compost composite fertilisers 2) using a scale-up approach, test the efficacy of composites in lab-scale, greenhouse pot, and field scale studies against commercially available fertilizers 3) carry out Life Cycle Analysis (LCA) and assess the benefits of the technology in terms of climate mitigation, economic outcomes and assess the environmental risks 4) Establish multiple channels of dissemination to implement the new approach of utilizing locally available waste to create fertilizers. The project will support the transition towards a sustainable circular economy and answer six UN SDGs. NIBIO in Norway will work closely together with the European consortium to help connect the aquaculture/marine industries with agriculture and create a waste-based innovative fertilizer - from co-composting e.g. fish sludge, kelp residues or other locally available wastes - that can sustain national food production and is less affected by geopolitical disruptions than mineral fertilizers.