Assessment of the Contribution of Root and Microbial Respiration to the Total Efflux of CO.sub.2 from Peat Soils and Podzols in the North of Western Siberia by the Method of Component Integration

• Published in: Eurasian soil science Vol. 52; no. 2; p. 206
• Main Authors: Goncharova, O. Yu, Matyshak, G. V, Bobrik, A. A, Timofeeva, M. V, Sefilyan, A. R
• Format: Journal Article
• Language: English
• Published: Springer 01-02-2019
• Subjects: Methods; Microbiota (Symbiotic organisms); Peat; Soils
• ISSN: 1064-2293
• DOI: 10.1134/S1064229319020054

The method of component integration was tested in the course of studies in typical biogeocenoses of the north of Western Siberia. This method as applied for separate horizons made it possible not only to estimate the contribution of different sources to the total efflux of CO.sub.2 from soils but also to evaluate the participation of horizons in soil respiration. Root respiration contributed to about 14 ± 3% of the CO.sub.2 efflux from the permafrost-affected peat soil (Hemic Cryic Histosol) and to about 29 ± 6% of the CO.sub.2 efflux from the tonguing podzol (Glossic Albic Rustic Podzol (Arenic)). Histosol was characterized by a higher storage of total (organic and inorganic) carbon (26 kg C/m.sup.2), extractable carbon (C.sub.extr) (32 g C/m.sup.2), and microbial carbon (C.sub.mic) (43 g C/m.sup.2). Its upper horizon (TO) contained about 50% of the total soil storage of C.sub.mic and 100% of the total storage of roots (up to 300 g/m.sup.2). It had the maximum activity of microbiota and contributed to more than 70% of the total efflux of CO.sub.2 from the active layer (on average, 35 cm in thickness) of Cryic Histosol. Podzol was characterized by the low storage of total carbon (6 kg C/m.sup.2), considerable storage of C.sub.mic (38 g C/m.sup.2), and much higher microbial activity. This circumstance, together with a tenfold higher storage of the roots (up to 3000 g C/m.sup.2) and favorable temperature regime specified high values of the gross production of CO.sub.2 and its emission from the Podzol surface exceeding the corresponding values for the Cryic Histosol by three-five times. The mineral profile of Podzol contributed to about 20% of the total efflux of CO.sub.2 from this soil (on average, about 38 cm in thickness).