Remotely Sensed Soil Moisture Effects on Carbon Sequestration Spatial Patterns

Carbon emission and fixation fluxes are key variables to guide climate change stakeholders on the use of remediation techniques. To develop Kyoto Protocol support tools, a sound application perspective is offered by expert systems based on earth observation (EO). This allows estimates of vegetation carbon fixation using a minimum of meteorological data. The core module of this type of expert systems is a production efficiency based model (C-Fix). C-Fix estimates the carbon mass fluxes, gross primary productivity (GPP), net primary productivity (NPP) and net ecosystem productivity (NEP) for various spatial scales. Global carbon budget studies are still dominated by temperature driven approaches only. Nevertheless, a strong coupling between the carbon and the hydrological cycles exists. To take water limitation in carbon studies into account, water availability for vegetation must be estimated, preferably with Earth Observation (EO). However, the strong coupling between the carbon and hydrological cycles is a longstanding acquisition of ecophysiology. When taking account of soil moisture as water limiting factor of ecosystem carbon models or not, ecosystems can revert from a net carbon source to a net sink and vice versa. The main ecosystem compartment responsible for these source sink shifts is identified as the soil compartment. Hence soil moisture singles out as a quite important determinant for carbon sequestration and proves to have a strong impact on carbon sequestration spatial patterns. * Corresponding author.