CARBON DISTRIBUTION IN MEADOW FESCUE (FESTUCA-PRATENSIS L) DETERMINED IN A GROWTH CHAMBER WITH C-14-LABELED ATMOSPHERE

The distribution of assimilated carbon on above- and below-ground plant parts, soil and soil-root respiration was determined in a perennial grass during seven weeks after germination. In a growth chamber with C-14-labelled CO2 in the atmosphere, meadow fescue plants were grown in sealed pots. Respired (CO2)-C-14 from roots and microbial decomposition of root material was collected and determined during growth. After seven weeks, 50% of the assimilated carbon was translocated below ground and 19% was released from the roots to the soil. Of the carbon released from the roots, one-fourth was found in the the soil and the rest was determined as soil-root respiration.