Impact of climate change on carbon partitioning
Levels of CO2 in the atmosphere are expected to increase in the future. State-of-the-art equipment used by the EUROFACE project allowed experiments to be carried out into the effects of increased CO2 on agro-forest plantations. Results from Black Poplar (P. nigra) trees enabled researchers to predict the negative effects on wood due to raised levels of CO2. This question needs to be answered because wood is a material of considerable economic importance. The main effect of elevated CO2 was an increase in biomass. However, the level of carbon partitioning between mobile and immobile C-pools was not affected significantly. This demonstrated the ability of P. nigra to maintain constant carbon levels under changing environmental conditions. Carbon-based secondary compounds, concentrations of total nitrogen (N) and lignin-bound N were also measured in P. nigra. The intention was to identify how secondary metabolites and internal nitrogen pools responded to raised CO2 and N-fertilisation. The results indicated that neither elevated CO2 nor an increased supply of nitrogen changed nitrogen partitioning between lignin bound nitrogen and other nitrogen containing compounds. A positive correlation was shown between the biosynthesis of proteins and secondary compounds. This indicated a link between growth and biochemical defence mechanisms of P. nigra in the plantation.
