Comparing soil microbial eco-physiological and enzymatic response to fire in the semi-arid Zagros woodlands

[Display omitted] •Soil enzymatic activity generally decreased 1 year after fire but recovered with time.•Inversely the specific activity of enzyme increased 1 year after fire.•Microbial metabolic quotient (qCO2) also increased 1 year after fire.•Specific activity of enzymes is found the most fire responsive variable. Fire is a major ecological factor altering soil properties that may remain for a long time. Little is known about the sensitivity to fire and post-fire recovery in soil microbial and biochemical properties in the semi-arid woodlands. The main objective of this study was to compare the changes in some microbial and biochemical properties in different years after fire. This study was conducted across a wildfire chronosequence in the semi-arid Zagros oak woodlands. We considered three fire treatments including 1, 3, and 10 years after fire. Then the soil samples were collected in a completely random design from each of the treatments. Soil microbial eco-physiological and enzymatic activities were measured for all the treatments and their relevant unburned control. The results indicated that soil organic carbon (Corg) decreased 1 year after fire (27%) and still remained lower for 3 years after fire (22%) and even for 10 years after (21%) compared to the controls. Microbial biomass carbon (Cmic) significantly decreased (77%) 1 year after the fire, whereas the value of basal respiration (BR) remained unchanged. The value of Cmic for the treatments 3 and 10 years after fire recovered to the unburned level. 1 year after the fire the ratio of BR to Cmic (qCO2) was three times as much as the control. Although the value of BR was lower (p