EGU General Assembly 2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.

Demography DGVMs, Forest Management, Reforestation, and Afforestation: Evaluations of JULES-RED at a Sitka Spruce Plantation

Arthur Argles1, Eddy Robertson1, Anna Harper2, James Morison3, Georgios Xenakis4, Astley Hastings5, Jon Mccalmont5,6, Jon Moore2, Ian Bateman7, Kate Gannon7, Richard Betts1,8, Stephen Bathgate4, Justin Thomas5, Matthew Heard9, and Peter Cox2
Arthur Argles et al.
  • 1Met Office Hadley Centre, FitzRoy Road, Exeter, Devon, EX1 3PB, UK
  • 2Department of Mathematics and Statistics, Faculty of Environment, Science and Economy, University of Exeter, Exeter, EX4 4QE, UK
  • 3Forest Research, Alice Holt Lodge, Surrey, GU10 4LH, Farnham, UK
  • 4Forest Research, NRS, Roslin, Midlothian EH25 9SY, UK
  • 5School of Biological Sciences, University of Aberdeen, King's College, Aberdeen AB24 3FX, UK
  • 6Department of Biosciences, Faculty of Health and Life Sciences, University of Exeter, Streatham Campus, Rennes Drive, Exeter EX4 4RJ, UK
  • 7Land, Environment, Economics and Policy Institute (LEEP), Department of Economics, University of Exeter Business School, Exeter, UK
  • 8Global Systems Institute, University of Exeter, Exeter, EX4 4QE, UK
  • 9The National Trust, Heelis, Kemble Drive, Swindon, SN2 2NA UK

Afforestation and reforestation are necessary for many countries to meet their Nationally Determined Contributions (NDC) and Net Zero targets (Seddon, N. et al 2019). Many countries estimate carbon sequestered using simple land-based transitions (IPCC, 2006) or have more complicated empirical estimations of carbon sequestered through forestry (Thomson, A. et al. 2020). This often leads to differences between NDC inventory submissions and bio-geophysical land surface modelling (Grassi, G. et al 2022).   The increasing representation of plant/tree demography within the latest Dynamic Global Vegetation Models (DGVMs) (Argles, A. et al 2022) and the availability of higher resolution regional climate datasets, provides new scope to evaluate modelled estimates against national inventories and Net Zero policies. As much afforestation is likely to be in the form of managed forests (Bateman, I.J, et al. 2022), the impact of management needs to be represented within models. We evaluate the JULES-RED model (Argles, A. et al 2020) against measured C stocks and fluxes at Harwood Forest, a Sitka spruce plantation in the UK. Planted in 1973, we will show that the inclusion of thinning in JULES-RED contributes to a more realistic representation of the 2018 carbon stocks and tree size-structure. We estimate a non-linear initial age-effect followed by a linear divergence between fixed and varying CO2 simulations, highlighting the need for better understanding of the effect of CO2 fertilisation in even-age stands and plantations.

How to cite: Argles, A., Robertson, E., Harper, A., Morison, J., Xenakis, G., Hastings, A., Mccalmont, J., Moore, J., Bateman, I., Gannon, K., Betts, R., Bathgate, S., Thomas, J., Heard, M., and Cox, P.: Demography DGVMs, Forest Management, Reforestation, and Afforestation: Evaluations of JULES-RED at a Sitka Spruce Plantation, EGU General Assembly 2023, Vienna, Austria, 24–28 Apr 2023, EGU23-14276,, 2023.