Are nutrients limiting the uptake of CO2 in forest ecosystems now, or are they likely to in the future?

The response of forest ecosystems to elevated CO2 levels is one of the major uncertainties in understanding the current and future potential impact of increased CO2 emissions 1.
Free-Air Carbon Dioxide Enrichment experiments are the most direct and robust platform to study the effects of elevated CO2 on woodland/forest ecosystems. Experiments currently underway include EucFACE2 and AmazonFACE3 on subtropical and tropical forests.
The Birmingham Institute of Forest Research (BIFoR) have built Europe’s first FACE experiment, set in Mill Haft Research Woodland, Staffordshire, UK4. BIFoR focuses on understanding the impact of climate and environmental change on temperate mature woodlands and the resilience of trees to pests and diseases.
Climate scientists and modellers have hypothesised forests/woodlands ecosystems could help reduce climate change by taking up excess CO2. However, these ecosystems could become nutrient limited in a future climate (elevated in CO2) and this could restrict CO2 uptake.
This FACE experiment will provide unique opportunity to fully understand the interactions between nutrient and carbon cycles in temperate mature woodland in a future elevated CO2 climate.
Research Question:
Do other macro- or micro-nutrients limit the uptake of CO2 in mature temperate deciduous woodland ecosystems now, or are they likely to in the future?

Objectives:
1) To undertake a detailed soil characterisation study
2) To quantify soil nutrient cycling processes and fluxes
3) To determine the impact of elevated CO2 on woodland soil ecosystems