Reserves of carbon in the organic matter of postfire pine forests in the southwest of the Baikal region

Abstract

A change in the mass and composition of organic matter in the phytomass and soil of pine forests affected by mid-intensity and high-intensity fires is considered. It is shown that a mid-intensity fire did not catastrophically affect the pool of carbon in the middle-aged pine forests of the subtaiga forest-steppe and the taiga higher belt areas in the southwest of the Baikal region. Five years after a high-intensity fire, the carbon reserves in a mature taiga pine forest remain 20% lower than in an unaffected pine forest. Compared with the reference figures, the mass of C and soil cover in the stand phytomass decreased by 18 and 63%, respectively. In the easily mineralizable fraction of organic matter, the reserves of carbon decreased by half owing to burnout of waste wood (by 64%) and root detritus (by 50% compared with the reference tree stand figures).