Journal Article

Evaluation of Direction and Mechanisms of Biochar Application Effect on Substrate-Induced Soil Respiration in a Long-Term Laboratory Experiment

Valeeva, A. A., Smirnova, E. V., Ryazanov, S. S., Giniyatullin, K. G., Okunev, P. V.

2023

Overview

In a laboratory experiment, the effect of biochar (BC) on substrate-induced respiration (SIR) of soils was studied. In the experiment, 10 samples of BC obtained from woody and herbaceous materials in two modes of pyrolysis were used. The SIR was determined after 3 days and after 3 and 6 months of incubation. During short-term incubation, no effect of BC on SIR was observed. The exception was the corn-based BС application, when there was a 34.6% increase in SIR. After incubation for 3 months, a significant increase in SIR was found (from 30.4 to 54.8%) for five BCs were added. After incubation for 6 months, a significant increase in SIR (from 30.4 to 65.9%) was observed when eight BCs were applied. LASSO regression and 23 parameters of BC properties were used as potential predictors to evaluate BC properties that affect SIR. It was found that during three-day incubation, the following properties of BС have a positive effect on SIR: the contents of oxidizable organic matter (OM) and exchangeable calcium and the pH of water suspension; the content of exchangeable sodium had a weak negative effect. At incubation for 3 months there is a positive effect of oxidized OM; and after 6 months, the ash content. Since only a positive statistically significant effect of BC on SIR was observed in the experiments, it was concluded that in order to objectively assess the efficiency of BC use for CO 2 sequestration in soils, balance calculations are necessary. In these calculations, along with the amount of stable carbon introduced into soils with BC, a potential increase in CO 2 emissions from soils due to the activation of soil saprophytic microbiota should be taken into account.

• Publisher: Pleiades Publishing,Springer,Springer Nature B.V
• Subject: Agricultural production / Agriculture / Ash content / biochar / Calcium / carbon / Carbon content / Carbon dioxide / Carbon dioxide emissions / Carbon dioxide fixation / Carbon sequestration / Charcoal / Climate change / Earth and Environmental Science / Earth Sciences / Emissions / exchangeable calcium / exchangeable sodium / Geotechnical Engineering & Applied Earth Sciences / Incubation period / Laboratory experimentation / Mathematical analysis / Meta-analysis / Microbial flora / Microbiota (Symbiotic organisms) / microorganisms / Mineralization / Organic matter / Organic Matter and Microbial Activity of Soil / oxidation / Pyrolysis / Respiration / saprophytes / Sodium / Soil / soil respiration / Soils / Statistical analysis / Substrates