Effects of forest fire on pectinolytic micro-organisms in the soil

Abstract: The effects of forest fire on the number of pectinolytic micro-organisms in soil was studied in burnt soil and unburnt soil. The soil samples were diluted to 10-3 and plated out on pectin agar at 28 °C. After incubation for 3-5 days, 10% lead acetate solution was poured on to the plates. The colonies which produced a clear zone were only bacteria. Forest fire reduced the number of pectin-utilizing bacteria in surface soil, but it had no effect on bacteria at a depth of 10 cm. (T-test P < 0.05). Forest fire caused pH to increase but water content, organic matter and nitrogen to decrease.