Macronutrient Cycles

Photo: river

Macronutrient cycles - nitrogen (N), carbon (C) and phosphorus (P) - are pivotal in the stability of global biogeochemical cycles, in sustaining natural resources and in protecting human health and biodiversity. Human activities have enhanced global cycles of N and P by on average 100% and 400%, respectively.

The overall goal of the Macronutrient Cycles programme is to quantify the scales (magnitude and spatial/temporal variation) of N and P fluxes and nature of transformations through the catchment under a changing climate and perturbed C cycle. NERC has allocated £9·55m to this programme.

Macronutrient Cycles: Science meeting at the Royal Society of London

24 Feb 2016

A two-day meeting on 15-16 June 2016 to present the results of the research and address key issues for policy makers and stakeholders.


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Macronutrient cycles - nitrogen (N), carbon (C) and phosphorus (P) - are pivotal in the stability of global biogeochemical cycles, in sustaining natural resources and in protecting human health and biodiversity.

Human activities have enhanced global cycles of N and P by on average 100% and 400%, respectively. Our perturbation of these natural cycles is changing the balance of interactions between them but the singular focus on C cycling in climate change research constrains our understanding of feedbacks between cycles and may result in unintended outcomes as our effort shifts to mitigating climate change impacts.

Elevated N (largely from food production and burning of fossil fuels) and P (from sewage industry and agriculture) compromise the ecosystem services on which we depend through degradation of natural resources (soils, freshwater) and loss of biodiversity; they affect human health through poor drinking water quality and for N, through reductions in air quality.

Evidence is growing that aquatic nutrient enrichment strongly influences the fate and effects of other non-nutrient contaminants, including pathogens. Highly contested is the claim that exclusive focus on P control in rivers has exacerbated N-limited downstream eutrophication in estuaries and coastal waters. Dual N and P control along the entire freshwater-marine continuum may be the solution. Similar debates exist in the atmosphere-terrestrial-freshwater domain linked to the yet unresolved contribution of anthropogenic N to a changing climate.

The overall goal of the Macronutrient Cycles programme is to quantify the scales (magnitude and spatial/temporal variation) of N and P fluxes and nature of transformations through the catchment under a changing climate and perturbed C cycle. We define 'the catchment' as covering exchange between the airshed and land surface through to the freshwater-estuarine boundary.

Aims and objectives

Delivery of the programme will be through four objectives, linking the different science areas and impacts:

  1. To evaluate the nature and scale of macronutrient (N, C) exchange between the airshed and terrestrial system and consequences for losses (N, P, C) to freshwater and atmosphere systems (atmosphere-terrestrial-freshwater feedback system).
  2. To determine the role and spatial and temporal variation of macronutrients (N, P, C) on key limiting processes and ecosystem functions (i.e. decomposition, productivity) and consequent export at the catchment scale (terrestrial-freshwater systems).
  3. To advance understanding of the co-limitation of N/P for eutrophication control along the entire freshwater system to the estuarine boundary (freshwater system).
  4. To determine the implications of nutrient enrichment on the fate and effects of other non-nutrient contaminants, including impacts on human health (i.e. pathogens, ozone) and biodiversity.

All of the objectives have technology science challenges embedded in them.

Timing

2011-12 - 2014-15

Can I apply for a grant?

An announcement of opportunity was published in summer 2011. There are currently no open calls.

Budget

£9·5m is available for this programme which directly relates to the delivery of the NERC strategy and addresses science challenges across five of the themes; sustainable use of natural resources (£3m); Earth system science (£1·5m); biodiversity (£2m); environment, pollution & human health (£2m); and technology (£1m).

Awards

Five consortia grants and two proof of concept grants have been funded.

Funded projects (PDF, 74KB)