TREE4FLUX - Monitoring trees in intensive, large-scale and long-term inventory plots for scaling eddy covariance carbon dioxide fluxes in Congo basin forests

The TREE4FLUX project is funded under the first phase of the ESFRI-FED program (Support for the valorisation of federal components of distributed and virtual ESFRI research infrastructures; 2021 – 2026) of BELSPO (CONTRACT NR EF/211/TREE4FLUX). This is a consortium project between the Africamuseum (PI Wannes Hubau, co-PI Hans Beeckman) and UGent (co-PI’s Pascal Boeckx, Hans Verbeeck, Marijn Bauters). The TREE4FLUX project supports the participation of the Wood Biology Service of the Royal Museum for Central Africa (RMCA) in the UGent-led eddy covariance (EC) CongoFlux tower located in Yangambi (D.R.Congo). The first ambition of TREE4FLUX is to complete the labelling process for CongoFlux and subsequently maintain the label of associated station in the Integrated Carbon Observation System (ICOS), by generating the first continuous multi-annual series of greenhouse gas (GHG) fluxes measured above African old-growth rainforest. A second ambition is to tackle the shortcomings inherent to the ‘top-down’ EC approach, by capitalizing on combined RMCA and UGent expertise to develop, consolidate and structurally organise ‘bottom-up’ tree monitoring infrastructures in and around the CongoFlux footprint (the area actually monitored by the EC equipment). These infrastructures will consist of three types of permanent forest inventory plots (intensive, large-scale and geographically dispersed) and the in situ RMCA-led Yangambi wood laboratory. The bottom-up data will be used to validate, complement and strengthen top-down CO2 flux data and will be uploaded as ancillary data to the ICOS carbon portal, which will firmly anchor the position of the combined infrastructures within ICOS. By combining RMCA and UGent-led infrastructures, TREE4FLUX will turn Yangambi into the first ‘supersite’ to measure CO2 fluxes in the African tropical rainforest. Combined data will enable robust upscaling of CO2 fluxes, providing benchmark estimates for (inter)national policy, which will further valorise the infrastructures. CongoFlux and its bottom-up infrastructures will complement the ICOS-labelled Guyaflux station in French Guyana. Together, these stations will enable ICOS to capture tropical forest ecosystem responses to climate change and contribute to a complete understanding of global GHG cycles.