Fire considerably influences the physical and chemical properties of soils as it substantially changes the soil characteristics both directly during burning and indirectly during the post-fire recovery period. We investigated how different fire regimes affect soil properties in the Miombo woodlands of Zambia. Soils were sampled incomplete fire protected, early burning and late burning plots and analysed for bulky density, soil solids, moisture content, soil porosity, soil pH, available phosphorus, total nitrogen, organic carbon, total carbon, calcium, magnesium and electrical conductivity. The results show that moisture content significantly (P<0.05) varied with treatment, soil horizon and their interaction effects. The late burning plot had reduced soil moisture than the early burning plot. Moisture content was significantly higher in the A horizon. Bulk density and total porosity did not significantly vary with treatment, but with soil horizon. Soil pH and soil Phosphorus did not significantly vary with treatment, soil horizon whereas electrical conductivity (EC), organic carbon, total carbon, potassium (K), calcium (Ca) and magnesium (Mg) significantly varied with treatment and soil horizon. Nitrogen varied marginally (P =0.0495) with treatment. It was slightly higher in a complete fire-protected plot. But it didn't vary with the horizon. Late burning increased EC over early burning and EC was higher in the A horizon. Over the years due to regular fire occurrences especially in old-growth miombo, it has been difficult to maintain forest health and prevent decline in soil elements.
Keywords: burning plots, fire regimes, soil properties, miombo woodlands