Effect of Forest fire on soil nitrogen mineralization and microbial biomass: A review

Abstract

Fires are one of the main feature of forest disruption and renovation. Different physical, chemical, mineralogical and biological properties of soil is ai¬€ected by forest i¬res as a result of burn severity, which consists of peak temperatures and duration of the i¬re. Forest fires generally reduce the total nutrient pool of a site through some combination of oxidation, volatilization, ash transport, leaching, and erosion. Fire leads to the rapid transformation of organic form of nitrogen to inorganic forms. Fire causes alterations of the abiotic environment, which in turn lead to changes in biotic processes and soil micro fauna. Fire results in increase in nitrogen mineralization rate due to rapid increase of inorganic nitrogen. However, with the passage of time net mineralization decreases due to destruction of organic matter. Further, fire can affect soil microbes directly through heating and indirectly by modifying soil properties. Fire causes a drastic reduction in soil microbial biomass. In general, bacteria are more tolerant to heat than fungi, therefore, it is commonly observed that burning favours bacteria over fungi.