UK roadmap for managing phosphorus

Phosphorus is a vital element within all animal and plant-based food systems, but phosphate fertiliser prices remain at a very high level after spiking last year. Phosphorus is also one of the main drivers of poor water quality in the UK’s rivers and lakes.

The strategy outlines a pressing need for new solutions and scaling up of existing phosphorus innovations to prevent future damage to aquatic biodiversity and habitats, reduce reliance on risky import markets and unlock new opportunities for agriculture.

Management of phosphorus

Dr Erin Sherry, principal research economist at the Agri-Food and Biosciences Institute (AFBI) and report co-author, said management of phosphorus is particularly important in terms of improving productivity – getting the same output with fewer inputs – while reducing the impact of food production.

“Profits benefit because taking full advantage of phosphate stocks reduces fertiliser purchases, and targeted use of slurry to replenish low stocks helps to improve grass growth, which reduces the feed bill as well.”

Phosphorus a lynchpin

Phosphorus is a lynchpin within the global food system – plants cannot grow without it and it has no substitute.

Crop and livestock production in the UK is almost entirely dependent on imported phosphorus in feeds and fertilisers, with the country importing 174,000 tonnes a year. This is mainly through phosphate rock from countries including Russia, China and Morocco.

Prices have quadrupled between mid-2020 and 2022 due to supply disruptions and market concentration in China. The ongoing war in Ukraine is serving to highlight the food security risks associated with reliance on imports of critical farm inputs like phosphorus.

Inefficient use

The report highlights that despite volatile prices and supply disruptions, phosphorus use in the UK is still highly inefficient, with less than half of imported phosphorus used productively to grow food. Poor management of phosphorus over decades has led it to being a major contributor to environmental problems. Wastewater discharges, along with excess phosphorus accumulating in agricultural soils and leaching into rivers, lakes and waterways, are contributing to issues such as algal blooms.

Professor Paul Withers, lead investigator for the project, Lancaster University, said the UK urgently needed to have a coherent plan for managing phosphorus across the food system, either nationally, regionally or in catchments.

“Transforming the way phosphorus is used in the UK food system is essential. Getting it right provides huge benefits to food and water security, tourism opportunities and to maintain a clean and healthy environment to boost biodiversity and the natural world for generations to come – but it requires all sectors to come on board,” he added.

Recommendations

The Strategy’s recommendations – agreed with national stakeholders including farmers, regulators, policy makers, wastewater companies, food producers and environmental NGOs – highlight a number of priorities to enable the UK to transition towards using phosphorus more sustainably:

• Develop and deploy at scale new technologies and innovations that can recover phosphorus from animal manure, wastewater and food waste, and redistribute as viable, cost-effective and renewable fertilisers.

• Provide incentives that encourage investment in technologies and lower barriers to create new markets for a renewable phosphorus fertiliser sector.

• Improve, align and make coherent policies and governance that recognise and manage phosphorus as a scarce resource, as well as a pollutant.

• Provide tailored knowledge, research and advice to farmers on tapping soil legacy phosphorus and using recycled phosphorus.

• Better engaging of stakeholders across the value chain to set strategic direction and support implementation via bespoke and diverse local phosphorus solutions.

• The creation of a nutrient stakeholder platform and UK nutrient data sharing dashboards to help inform phosphorus management.

The good news is that there are many pockets of innovation and initiatives already underway in different sectors in the UK.

Uneven concentration across the UK

The report also highlights the uneven concentration of phosphorus across the UK with surpluses seen in the predominantly livestock areas of western England and Northern Ireland. The excess phosphorus applied in England’s North West region is equivalent to nearly £30m of fertiliser.

In areas where arable crops are grown, mainly in eastern England, there is a deficit, and there is a need to use phosphorus-based fertilisers because crops are taking up more than is applied.

However, the logistics of moving bulky manure from one part of the country to another are impractical and so finding innovative ways of extracting and relocating phosphorus from manure will be key in addressing the regional imbalances.

Theoretically, there is enough phosphorus circulating in the food system and in our soils.

Accessing legacy phosphorus bank

The report adds there is millions of pounds of phosphorus locked in UK top soil from decades of applications of fertiliser and manure. Accessing and managing this legacy phosphorus “bank” is central to improving efficiency and reducing imports.

Fellow lead author, Associate Professor Brent Jacobs said: “The good news is that there are many pockets of innovation and initiatives already underway in different sectors in the UK. These can be learned from, scaled up and integrated to help overcome some of the challenges associated with phosphorus use.

“Theoretically, there is enough phosphorus circulating in the food system and in our soils. One of the pathways to achieving sustainable phosphorus use will involve developing new technologies that can extract legacy phosphorus from soils and manures and develop new renewable fertiliser markets.”

Professor Julia Martin-Ortega, from the University of Leeds and report co-author, added: “As the UK food system is undergoing fundamental policy change, our report provides a timely opportunity to integrate urgently needed actions across all the sectors of the food chain into regional and national policy and governance, tapping into huge potential wins for the environment and the economy.”

The full report