CONTRIBUTION TO THE WINTER WHEAT (Triticum aestivum sp.) CARBON BALANCE ELABORATION: CROP GROWTH AND BIOMASS MONITORING

This field trial aimed to follow the crop development evolution, to measure its net primary production (NPP) and the exchanged carbon flows and to study the relations between them and the crop growth and development. The crop intercepted between 90 and 95 % of the PAR (Photosynthesis Active Radiation). During the period of intense growth, GLAI (Green Leaf Area Index) rised up to 3 m² per m². The VAI (Vegetation Area Index) measured following two methods was close to 5 at the end of the growth season. Aerial biomass carbon content has shown no variation (43%) and thus the biomass evolution has been parallel to the cumulated NPP evolution. Part of the carbon has been exported from the field by grains and straws (5.8 t C/ha), part has been incorporated into the soil through the residues and roots (3.0 t C/ha).