|NUKLEONIKA 2002, 47(Supplement 1):s59-s61
RESPIRATION AND ASSIMILATION PROCESSES REFLECTED
IN THE CARBON ISOTOPIC COMPOSITION OF ATMOSPHERIC CARBON DIOXIDE
Janina Szaran, Halina Niezgoda, Andrzej Trembaczowski
Institute of Physics, M. Curie-Sklodowska University,
1 M. Curie-Sklodowska sq., 20-031 Lublin, Poland
This paper presents diurnal variations of concentration and carbon isotopic composition of atmospheric carbon dioxide caused by respiration and assimilation processes. Air samples were collected during early and late summer in 1998 in unpolluted area (village Guciow located near the Roztocze National Park, SE Poland) in three different environments: uncultivated field on a hill, a meadow in the Wieprz river valley and a forest. The effect is very strong during intensive vegetation growth on a sunny day and clear night. The largest diurnal variations in atmospheric CO2 concentration and its carbon isotopic composition in June above the meadow were about 480 ppm and 10‰, respectively.