Modelling long-term impacts of changes in climate, nitrogen deposition and ozone exposure on carbon sequestration of European forest ecosystems

Wim de Vries; Maximilian Posch; David Simpson; Gert Jan Reinds

doi:10.1016/j.scitotenv.2017.06.132

Modelling long-term impacts of changes in climate, nitrogen deposition and ozone exposure on carbon sequestration of European forest ecosystems

Sci Total Environ. 2017 Dec 15:605-606:1097-1116. doi: 10.1016/j.scitotenv.2017.06.132. Epub 2017 Jul 19.

Authors

Wim de Vries¹, Maximilian Posch², David Simpson³, Gert Jan Reinds⁴

Affiliations

¹ Wageningen University and Research, Environmental Research (Alterra), PO Box 47, NL-6700 AA Wageningen, The Netherlands; Wageningen University and Research, Environmental Systems Analysis Group, PO Box 47, NL-6700 AA Wageningen, The Netherlands. Electronic address: wim.devries@wur.nl.
² Coordination Centre for Effects (CCE), RIVM, PO Box 1, NL-3720 BA Bilthoven, The Netherlands.
³ EMEP/MSC-W, Norwegian Meteorological Institute, PO Box 43-Blindern, N-0313 Oslo, Norway; Dept. Space, Earth & Environment, Chalmers University of Technology, SE-412 96 Gothenburg, Sweden.
⁴ Wageningen University and Research, Environmental Research (Alterra), PO Box 47, NL-6700 AA Wageningen, The Netherlands.

PMID: 28738517
DOI: 10.1016/j.scitotenv.2017.06.132

Abstract

We modelled the effects of past and expected future changes in climate (temperature, precipitation), CO₂ concentration, nitrogen deposition (N) and ozone (O₃) exposure (phytotoxic ozone dose, POD) on carbon (C) sequestration by European forest ecosystems for the period 1900-2050. Tree C sequestration was assessed by using empirical response functions, while soil C sequestration was simulated with the process-based model VSD, combined with the RothC model. We evaluated two empirical growth responses to N deposition (linear and non-linear) and two O₃ exposure relationships (linear function with total biomass or net annual increment). We further investigated an 'interactive model' with interactions between drivers and a 'multiplicative model', in which the combined effect is the product of individual drivers. A single deposition and climate scenario was used for the period 1900-2050. Contrary to expectations, growth observations at European level for the period 1950-2010 compared better with predictions by the multiplicative model than with the interactive model. This coincides with the fact that carbon responses in kgCha^-1yr^-1 per unit change in drivers, i.e. per °C, ppm CO₂, kgNha^-1yr^-1 and mmolm^-2yr^-1 POD, are more in line with literature data when using the multiplicative model. Compared to 1900, the estimated European average total C sequestration in both forests and forest soils between 1950 and 2000 increased by 21% in the interactive model and by 41% in the multiplicative model, but observed changes were even higher. This growth increase is expected to decline between 2000 and 2050. The simulated changes between 1950 and 2000 were mainly due to the increase in both N deposition and CO₂, while the predicted increases between 2000 and 2050 were mainly caused by the increase in CO₂ and temperature, and to lesser extent a decrease in POD, counteracted by reduced N deposition.

Keywords: CO(2); Carbon sequestration; Climate change; Forest; Nitrogen deposition; Ozone.