Transformation of organic matter of Cisbaikal forest-steppe abandoned lands

• Published in: IOP conference series. Earth and environmental science 2021-10, Vol.862 (1), p.12115
• Main Authors: Yu Zorina, S, Sokolova, L G, Dorofeev, N V, Kazanovsky, S G, Belousova, E N
• Format: Article
• Language: English
• Subjects: Abandoned land; Age; Carbon; Decomposing organic matter; Forest soils; Humification; Humus; Litter fall; Microorganisms; Nature reserves; Organic matter; Reserves; Residues; Soils; Steppes
• ISSN: 1755-1307; 1755-1315
• DOI: 10.1088/1755-1315/862/1/012115

For the first time, quantitative estimates of the carbon pools (plant residues, microbial biomass, and humus) that provide organic matter reserves in gray forest soils depending on the abandoned age are presented for the region. The pool of C-plant residues, which comprises only carbon reserves in the aboveground part of the herbaceous layer and litter fall, varied from 0.3 to 5.9 t·ha-1. Young fallows were observed to demonstrate the highest values. The increase in the age of the abandoned land was found to be accompanied by the decrease in carbon reserves in the plant pool. The microbial carbon pool (Cmic) varied from 2.1 t·ha-1 on young fallows to 5.2 t·ha-1 on long-term abandoned lands approaching the indicators identified for natural cenoses (6-8 t·ha-1). The largest value (25-72 t·ha-1) characterized the carbon pool in the humus, but no regular changes depending on the abandoned age were identified. The type of humus in the soils after abandonment, as well as in undisturbed soils, was fulvate-humate, and the degree of humification varied from “medium” to “very high”. This indicates the preservation of zonal features of humus formation of gray forest soils in the region during their postagrogenic development.