What are the hydrological controls on soil processes controlling carbon- and nutrient-efflux in the Critical Zone at the landscape scale?

• Main Authors: Henrion, Maud, Li, Yanfei, Thami, Adil, du Bois d'Aische, Eléonore, Jonard, François, Lambot, Sébastien, Opfergelt, Sophie, Vanacker, Veerle, Van Oost, Kristof, Day of the Young Soil Scientist 2023
• Other Authors: Uliège - Earth Observation and Ecosystem Modelling Laboratory, UCL - SST/ELI/ELIC - Earth & Climate
• Format: Conference Object
• Language: English
• Published: 2023
• Subjects: permafrost; Alaska
• Online Access: http://hdl.handle.net/2078.1/273809

The Critical Zone (CZ) provides many ecosystem services that are endangered by both climate change and human activities. It is subject to multiple processes in interaction at the interface of the atmosphere, biosphere, hydrosphere, and lithosphere, which complicate its integrative study. This project will develop a truly interdisciplinary CZ research allowing to understand more precisely some key CZ processes and their interactions. The use of advanced sensing technologies will also provide a framework for future CZ research. This project focuses on the spatio-temporal variations of soil hydrology and its control on carbon and nutrient fluxes in hillslope systems. This project will start by studying the long-term patterns of the Critical Zone (subsurface structure, soil characterization, topography, vegetation characterization, etc.) known to influence the shorter-term (sub)surface processes. Soil moisture and temperature will then be monitored using in-situ sensors and UAVs equipped with Ground-Penetrating Radar and thermal infrared camera. Their control on soil respiration, soil nutrients and dissolved organic carbon fluxes will be studied. These processes will then be used for smart modelling. First, a 3-D physical-based model will be developed to characterize water and heat dynamics. Then, using a deep neural network, additional data will be integrated to predict water, nutrient and carbon fluxes at the landscape scale. Despite the fact that peatlands play an important role in climate regulation, biodiversity support, water regulation, carbon storage, they are still understudied. Hence, this methodology will be first developed in a peatland landscape characterized by a clear topographic gradient in the Belgian High Fens. Then, it will be applied on a frozen peatland located in Alaska (USA), presenting a natural permafrost degradation gradient.