EFFECTS OF FIRE ON SOIL

Fire affects soils in many ways.  When fire burns the decomposing plant material on the surface of the ground, the nutrients stored up in that material are released, raising the surface soil pH.  These nutrients are taken up by other plants and microorganisms or are exported from the community.  Due to its importance as a major plant food source, nitrogen has been studied for its abundance before and after prescribed burning.  Research has demonstrated that fire actually induces nitrogen fixation by the soil microorganisms associated with plants and ends up replacing any nitrogen lost during the burning (Robbins and Myers, 1992).

Fire effects research has also been conducted on soils in regards to prescribed burning during dormant versus growing seasons (Schneider, 1988; Gilliam and Christensen, 1986).  Little substantial evidence has been produced from these studies to validate one claim over another.  What is evident is that differences in productivity among ecosystems can be attributed to seasonal variation in nutrient losses.  Since a majority of the soils in Florida are endemically low in nutrient levels and vegetation is so efficient in capturing nutrients released by burning, fire effects on soils in Florida seems to be less of an issue than in other ecosystems (Robbins and Myers, 1992).