Smoke Toxicity to the Biota and the Biological Activity of Soils When Modeling Fires.

Abstract—The results of a study on the effect of one type of pyrogenic factor (smoke) after burning coniferous wood chips on several bioindicators (soil enzymes, microorganisms, mesofauna, plants of agricultural crops) are presented. Exposure to smoke for 60 minutes was found to affect the enzymatic activity of the common chernozem significantly. Fumigation caused a decrease in enzymes such as catalase, peroxidase, polyphenol oxidase, and invertase. The enzymes of the oxidoreductase class were the most sensitive to smoke. The high toxicity of the gaseous combustion products to the soil flora and fauna was revealed. The acute toxicity of smoke to the bioindicators was determined as a result of fumigation. The high mortality of test objects (Eisenia fetida and Nauphoeta cinerea) was recorded in our experiments. Soil microorganisms (Azotobacter chroococcum and Penicillium chrysogenum) proved to be informative after 30–120 minutes of fumigation. The resistance of plant sprouts (Raphanus sativus, Triticum aestivum, and Pisum sativum) to gaseous combustion products was revealed. An experiment to analyze the chemical composition of gases in smoke was conducted. Hazardous compounds such as sulfur dioxide (SO2), nitrogen oxide and dioxide (NO, NO2), carbon monoxide (CO), acetaldehyde (C2H4O), formaldehyde (CH2O), phenol (C6H6O) hydroxybenzene, and others were found to be contained therein. Our analysis revealed that the concentrations of carbon monoxide were 714 times higher than its maximum permissible concentration (MPC), while that of acetaldehyde was 24 100 times higher. The nitrogen oxide and nitrogen dioxide concentrations were 100 and 300 times higher, respectively. [ABSTRACT FROM AUTHOR]