Macronutrient Cycles Programme draws to a close

The Royal Society hosts the finale of the £10.55 million Oxford-led research collaboration.

The Macronutrient Cycles Programme held its final workshop in June, drawing to a close the successful 5-year collaboration, led by Oxford University’s Professor Paul Whitehead and Dr Jill Crossman. The £10.55 million programme, funded by NERC, DEFRA and the Scottish Government, drew together expertise from 11 universities and 4 research institutes, to help better understand macronutrient cycles.

Over 110 researchers and stakeholders gathered at the Royal Society of London to hear the results of the research and implications for policy makers and catchment management stakeholders. The event featured an extensive stakeholder session including representation from DEFRA, the Environment Agency, Welsh Government, Scottish Government, River Trusts and Dr Ruth Kelman—Head of NERC’s freshwater sciences.

Macronutrient Cycles
Macronutrients – nitrogen (N), carbon (C) and phosphorus (P) – play pivotal role in the biogeochemical systems which sustain life. However, human activities, such as the burning of fossil fuels, food production and sewage discharges, have drastically altered macronutrient cycles, with significant implications for ecosystems and human health. Nitrogen and phosphorus cycles have accelerated globally by around 100% and 400% respectively on average.

Macronutrient Cycles Programme (MCP) sought to better understand these cycles, in particular to quantify the magnitude of nitrogen and phosphorus fluxes, their spatial and temporal variation, and how transformations occur through the catchment, in the context of a changing climate and perturbed carbon cycle. The term “catchment” was defined to address the exchange between the terrestrial, aquatic, atmospheric and estuarine systems. The programme sought not only to explore how these inter-related cycles limit ecosystems functions, but also and to examine what nutrient enrichment means for non-nutrient contaminants such as pathogens, and their impact up human health and biodiversity.

To realise this ambition the MCP funded the development of two innovative technologies, in addition to the following 4 projects:

1. LTLS: Analysis and simulation of the long-term/large-scale interactions of C, N and P in UK land, freshwater and atmosphere.
2. Turf2Surf: The multi-scale response of water quality, biodiversity and C sequestration to coupled macronutrient cycling from source to sea.
3. Quantifying annual cycles of macronutrient fluxes and net effect of transformations in an estuary: their responses to stochastic storm-driven events.
4. The role of lateral exchange in modulating the seaward flux of C, N, P.

Key Achievements

The research has contributed to long-term monitoring, providing great insight into how macronutrient sources have changed over the last 200 years. Data generated by the programme has helped improve modelling and aided the development of new models within the programme. These include a Bayesian model to further our understanding of seasonal variability and of how total fluxes of macronutrients respond to changes in river flow; a national scale model by developed to track the total leakage of phosphorus from water pipes; and two new catchment-scale models to address the effects of non-nutrient contaminants (pathogens and particulate organic pollutants).

In addition to modelling advances, the MCP supported the development of 2 innovative pieces of technology: a new ‘lab on a chip’ system for continuously monitoring nutrients in rivers and estuaries, and “Skyline 3D” a prototype system to remotely monitor greenhouse gases using a fly by wire remote gas collection system.

The MCP represents a major contribution to the current state of scientific knowledge of macronutrient cycles, which significant implications for environmental management. In total, the programme generated over 85 papers, and two special issue journals, with a third currently in press and expected to be published in the coming months.

Workshop presentations from the event will be available shortly on the Macronutrient Cycle Programme homepage. For further information about the programme contact Paul Whitehead –