C-CASCADES

'Anthropogenic perturbation of the global carbon cycle as a result of erosion-induced lateral fluxes of C: A study across spatial and temporal scales' by Dr. Kristof Van Oost

Dr. Kristof Van Oost's short biography:

Dr. Kristof Van Oost is Professor of Earth System Science at the Georges Lemaître Centre for Earth & Climate research of the Université catholique de Louvain.
His research interests are at the interfaces between geomorphology and soil science with a particular focus on geographical aspects and numerical modeling. He has contributed to the study of soil erosion processes and to the transport and cycling of sediment and nutrients in terrestrial ecosystems. During this research, model tools were developed, including 3-dimensional models of soil, fallout radionuclides and nutrient redistribution, which were used to study the effect of hydrological and geomorphic processes on soil dynamics. More recently, observational constraints using sediment tracers and C isotopes, soil incubation experiments, soil carbon fractionation techniques and in-situ soil CO₂ flux measurements were used to understand the mechanisms controlling carbon transformations as a result of mobilization, transport and deposition. This work also informed the development and evaluation of depth-explicit soil carbon models that are applicable to complex landscapes and depositional environments. Scaling up, Kristof also focused on the interactions between soil science, geomorphology and carbon cycling at regional scales in relation to management strategies and the regional carbon budget. At global scales, empirical models were developed to understand and quantify geomorphic processes and their interactions with the global C, N and P cycles. More recently, Kristof collaborates with Earth System modelers on the scaling of geomorphic parameters and the representation of Holocene agricultural erosion in Dynamic Global vegetation Models.

Dr. Kristof Van Oost's personal homepage

Lecture's abstract - 'Anthropogenic perturbation of the global carbon cycle as a result of erosion-induced lateral fluxes of C: A study across spatial and temporal scales':

Several processes contribute to the net uptake of carbon on land, but their precise quantification, geographical distribution and identification of underlying processes remains associated with large uncertainties. In particular, traditional analysis omit that carbon originally fixed by land plants is continuously displaced laterally along the Earth’s surface, from upland soils to streams and rivers and further down to the ocean. While a fraction of this laterally displaced carbon flux is a natural component of the global carbon cycle that can be ignored in the analysis, a substantial fraction is a perturbation that is relevant for the anthropogenic CO₂ budget. Using evidence from both experimental and modeling studies that cuts across spatial and temporal scales, we show that the perturbation of the C cycle, as a result of upland erosion and transfer, is large and has profound implications for the estimation of the amount of carbon stored on land. Finally, we discuss the consequences for the pre-industrial as well as for the present and future atmospheric CO₂ budget.

Recommended background publication on this presentation:

Hoffmann, T., Mudd, S. M., van Oost, K., Verstraeten, G., Erkens, G., Lang, A., Middelkoop, H., Boyle, J., Kaplan, J. O., Willenbring, J., and Aalto, R.: Short Communication: Humans and the missing C-sink: erosion and burial of soil carbon through time. Earth Surf. Dynam., 1, 45-52, (2013). Doi:10.5194/esurf-1-45-2013.