Vergara - 1976 - Physiological and morphological adaptability of ri

254 CLIMATE mo RICE
m; minim
MJNISQY I
mini’
Gunman»!
Duysmumim
4. Influence of temperature on the kinetics of denitritication in four submerged soils.
rate constants are low.
Brelnner and Shaw (1958) noted that the rate ofdenitlification was very‘ slow
below 5°C and increased rapidly in the range |5° to 60°C. Yamane and Sato
(1961) and also Cho and Ponnampertlma (1971) found that above 15°C nitrate
disappeared so rapidly that little was left in anaerobic soils after 2 Weeks incubation
in the range lS° to 40°C.
Gupta and Ponnamperutita (unpublished. 1974) found that the rate of denitrificatitin
increased markedly as the temperature rose from 5° to 45°C (Fig. 4).
They observed that the variation of the rate constant with temperature obeyed
the Arrhenius law:
k =.'I
exp (— Err/RT)
(where k is the rate constant. A is the frequency factor or pie-exponential factor.
Ea is the activation eitergy. and T is the absolute temperature) and that the values