PESAt
PLATFORM ON SOIL-ATMOSPHERE EXCHANGES IN WETLANDS
Peatlands have a crucial role in the fight against the greenhouse effect. If they represent only 3% of the surface of the globe, they have stored during the last 10 000 years not less than 30% of the carbon accumulated in the world soils. But it can be mineralized and emitted in the form of carbon dioxide or methane, two gases responsible for the greenhouse effect.
These unique ecosystems also contribute to the regulation of water flows and the preservation of biodiversity. These functions are however threatened by human activities or climatic disturbance, which by modifying the environmental conditions alter their function of “sinks” of carbon. It is necessary to determine whether these systems still continue to store carbon, or whether, on the contrary, they release it as a greenhouse gas (GHG) into the atmosphere or as organic carbon dissolved in water.
The PESAt platform, managed by the CNRS and the University of Orléans, has the major objective of developing an innovative metrology for the quantification, control and modeling of GHG emissions (CO2 and CH4) between peat soils and the atmosphere. The acquisition of high-frequency chronicles (1 flow per 30 minutes in theory) will thus reduce uncertainties on wetland GHG emission estimates and contribute to the improvement of global climate prediction models in which the large stock C of peat bogs is so far not taken into account.
The PESAt platform uses three types of measurements to evaluate carbon balance in gaseous, dissolved and particulate form:
- monitoring of carbon dioxide (CO2) and methane (CH4) fluxes followed by dissolved organic carbon (DOC) and particulate matter fluxes followed by water level
- water chemistry and weather
EN BREF
ORGANIZATION
CNRS
UNIVERSITY OF ORLÉANS
ISTO
THEMES
ATMOSPHERE
GROUND
BOG
WATER
GREENHOUSE GAS
CARBON WELL
METROLOGY
HA OF STUDY SITE
EMPLOYEES
3 TEACHER-RESEARCHERS – 5 ENGINEERS – 2 TECHNICIANS – 1 DOCTOR
PPROJECTS
1 NATIONAL, 2 REGIONAL
NATIONAL AND INTERNATIONAL NETWORKS
ICOS EUROPE, SNO TOURISTS, ICOS FRANCE, OZCAR, WORKSHOP AREA LOIRE
OUR SERVICES
The instrumental devices of PESAt are deployed on the site of the peat bog of La Guette (Cher). Experimental means (mesocosms and phytotron) and analytical tools (geochemistry (organic and inorganic) global, molecular and isotopic) are grouped together at ISTO (Orléans).
- Flux tower equipped with high frequency (20Hz) CO2, CH4 and H2O analyzers and a 3D anemometer for eddy covariance measurement of GHG fluxes (1 flow per 30 minutes).
- Soil temperature, soil water content and water level sensors for characterization of soil physics
- Heat flux sensors in the soil and net radiation for the estimation of the energy balance
- A meteorological station collecting the variables on the physics of the atmosphere and soil
- Manual static chambers deployed on site to measure the spatial variability of GHG fluxes
- Mobile automated chambers (under development) deployed for laboratory and other experimentation
- A set of measurement tools (piezometers with automatic probes, Exo2 multi-parameter probes) for the analysis of solid and dissolved organic matter
- Portable probes and laboratory analyzes to characterize the chemical quality of water (pH, conductivity and water temperature, ions including nutrients, DOC, dissolved nitrogen, MOD aromaticity, 3D fluorescence)
Most of the tools of the PESAt platform can be mobilized in the context of collaborative projects. Databases are also made available.
The applications of the PESAt platform are as follows:
- to achieve water balances, carbon and energy at the ecosystem level
- to understand the fate and transfer of dissolved organic carbon from wetlands to adjacent watercourses
- to create interoperable databases of greenhouse gas flows and to model these flows
- to improve global models of climate prediction
- to implement and validate GHG and DOC flux measurement tools at different spatio-temporal scales
- to measure the effect of biodiversity change on CO2 production and GHG fluxes
The PESAt platform provides the expertise of a team of technicians, engineers and researchers able to solve specific problems and carry out projects.
The PESAt platform is open to the scientific community and industrialists for one-off or larger studies, within the framework of:
- Collaborative projects on regional, national or european funding
- Services / expertises
- Training / Demonstration support
OUR PROJECTS
| CAREX PROJECT | Ongoing |
Validation of peatland restoration indicators (carbon, hydrology, biodiversity) for their sustainable management under the effect of climate change
| CARBIODIV PROJECT | Completed |
Hydrological restoration of a peat bog: effect on carbon storage and evolution of biodiversity
| PEATWARM PROJECT | Completed |
Impact of simulated global warming in situ on the carbon sink function of sphagnum peatlands
CONTACT
FATIMA LAGGOUN-DEFARGE
PESAt platform manager
Director of research at CNRS
02.38.49.46.63 / fatima.laggoun@univ-orleans.fr
ISTO/OSUC – Université d’Orléans – CNRS – 1A, rue de la Férollerie, 45071 Orléans Cedex 2
SÉBASTIEN GOGO
PRIME platform co-manager
Research professor at ISTO
02.38.49.45.02 / sebastien.gogo@univ-orleans.fr
ISTO/OSUC – Université d’Orléans – CNRS – 1A, rue de la Férollerie, 45071 Orléans Cedex 2
