ReBALAN:CE - Recycling Biomass to Agricultural LANd: Capitalizing on Eutrophication

This project will bring together an interdisciplinary team of experts from across academic, policy and stakeholder organisations in order to prioritise and plan a response to the pressing science needs associated with resource recovery from waste. Specifically, the project will explore nutrient recovery from excessive aquatic plant and algal biomass production in nutrient enriched waters (e.g. ponds, constructed farm wetlands, sustainable urban drainage systems and natural waterbodies) and, crucially, will integrate economic, social, environmental and health-related dimensions that cut across traditional academic disciplines. Thus, the overall aim of this project is to facilitate the exchange of knowledge across the disciplinary boundaries of biology, geography, soil and water science, microbiology, human behaviour, risk perception, waste management, economics and catchment management. In turn, we will develop a comprehensive, holistic and targeted programme of research to 'close the loop' on nutrient transfer from land to water. This will be underpinned by understanding and quantifying the risks, opportunities and multiple benefits of recycling excessive aquatic plant and algal biomass back to agricultural land.

The project will therefore contribute to a paradigm shift in current conceptualisation of 'waste' management to redress the current imbalance of focus on economic benefits of recovering resources from waste. In a wider context, effective and sustainable waste management must take account of the often unquantified and uncertain trade-offs for managing wastes across the environment. For example, recovering nutrients from aquatic plant and algal biomass makes economic sense because fertiliser costs are soaring due to shortages in mineral supply; however, this is only one part of a complex socio-economic-ecological system. We need to couple economics with the safeguarding of human health and protection of key ecosystem services, such as the provision of clean and safe recreational and drinking water, and appreciate the social and political barriers that may hinder or promote efficient nutrient recovery from this 'waste' by-product. While we know that anthropogenic inputs of nutrients to aquatic systems can be assimilated in aquatic biomass we have little knowledge on how pathogens and toxins may be recycled through agroecosystems following reapplication of this biomass to land, and poor understanding of nitrogen and phosphorus release rates from non-composted and composted biomass. Furthermore, the potential role for aquatic plant and algal biomass to be made into biochar (charcoal) as a novel approach to re-cycle nutrients and store carbon in soil (to offset emissions of carbon dioxide) is another dimension of resource recovery from waste by-products that might deliver multiple benefits and ecosystem services for wider society. There are a number of additional policy related dimensions to debate including whether there is an issue surrounding the classification of recycled biomass as non-waste in terms of regulation and licensing. Our team is well equipped with the expertise to develop core work-packages needed for a well balanced research agenda in recycling biomass to agricultural land.

The project team are therefore tasked with framing some important emerging questions that will need innovative science and integrated solutions for 2020 and beyond. By pooling the cross-disciplinary expertise assembled in this catalyst grant we will identify where improvements in fundamental understanding are necessary to deliver step changes in 'waste' management for environmental benefits and help refine regulatory policy and practice to support this.

Making the most of research findings remains a major challenge for environmental scientists, policy-makers and those implementing policy. This is especially important when considering resource recovery from agricultural 'waste'. Indeed, the recent Foresight report on the future of food and farming highlighted that the challenge for the agricultural sector was to increase productivity to feed a growing global population with dwindling resources in a changing climate while at the same time reducing environmental burdens. The core aims and objectives of this catalyst grant will contribute to the identification of solutions, and exploitation of opportunities, as part of tackling this major challenge.

Understanding and appreciating the magnitude and efficiencies of nutrient recovery from alternative and novel 'waste' sources is important to those who work in areas of research, policy and business linked to waste management and associated legislation. Ultimately this work seeks to improve quality of life for those enjoying recreational activities in rural environments and profitability for those reliant on the land to make a living. Policy makers and regulators will therefore gain immediately from the recommendations and priorities highlighted as part of this catalyst grant, and so the potential impact of research findings that would result from a larger programme of research would extend far beyond academic boundaries. The project has a striking relevance to current interest in environmental risks, with specific regard to risks arising from application to land of contaminated aquatic plant and algal biomass, and to the ecological functioning of aquatic environments if biomass harvesting is undertaken in haste without thorough cross-disciplinary assessment of the issue at hand. Fundamental knowledge in the area of maximising nutrient recovery from alternative sources has become high priority as agriculture undergoes unprecedented changes in response to climate change and food security drivers that in turn will inevitably challenge water quality throughout UK catchments. The involvement of Rescobie Loch Development Association (RLDA) highlights the importance of aquatic systems impacted by agricultural inputs of nutrients to those who use water for recreational pursuits. Their involvement provides a strong case study where pilot work has already been undertaken in partnership with the University of Stirling and James Hutton Institute to explore benefits of weed harvesting not only for loch-users but also for the surrounding agricultural community (farmers will be consulted as stakeholders within this project via the RLDA) and this issue, and associated debate, is transferable to all heavily eutrophic water bodies in the UK. In fact, the potential impact of the project transcends international boundaries with objectives aligning with the interests of the US Department for Agriculture and their Environmental Management and By-product Utilization Laboratory. With rapid economic development (in countries such as China for example) comes increased pressures on water resources, and increased frequency of the occurrence of algal blooms - again reinforcing the international scope for exploiting the findings of the ReBALAN:CE research programme.

The PI and Co-Is are well-placed to ensure that research findings are disseminated with highest impact given their existing links to the Scottish Government, Defra and other bodies. The PI has been engaged with all principal UK regulators and policy makers and is currently leading two NERC grants exploring the impacts of microbial pollution on catchment management. A working group established as part of one of these projects provides a key existing network of academic, public and policy partners and will act as an effective mechanism of further knowledge exchange.