Soil CO2 efflux in a beech forest: dependence on soil temperature and soil water content

Paris

1999

S. 221-226

4 Abb., 1 Tab., 19 Lit. Ang.

Bandaufführung

137659

Our objective was to quantify the annual soil carbon efflux in a young beech forest in north-eastern France (Hesse Forest, Euroflux Site FR02) from measurements of soil CO2, efflux. Soil CO2, efflux exhibited pronounced seasonal variations which did not solely reflect seasonal changes in soil temperature. In particular, strong differences in soil CO2 efflux were observed between summer 1996 and summer 1997 while the patterns of soil temperature were similar. This difference is at ieast partly explained by an inhibition of soil CO2 efflux at low soil water content. Since changes in soil temperature (T) and soil volumetrie water content at -10 cm affect soil CO2 efflux, an empirical model is proposed which account for 86 % of the variation in soil CO2 efflux.The difference between two estimates of annual soil carbon efflux clearly highlights the dependence of soil carbon efflux on soil water content during summer.