Biomass and Nutrients in Aboveground Vegetation and Soils of Florida Oak-Saw Palmetto Scrub

We sampled aboveground biomass in four stands of oak-saw palmetto scrub vegetation that were 2, 4, 8, and 25 years since the previous fire by harvesting 1 m2 plots. Biomass samples were analyzed for major nutrients. We sampled and analyzed soils from the 0-15 cm and 15-30 cm layers. Stands were dominated by Quercus myrtifolia, Q. geminata, Q. chapmanii, Serenoa repens, and ericaceous shrubs. Live aboveground biomass (excluding saw palmetto rhizomes) increased with time since fire. Litter biomass increased for eight years after fire. Standing dead biomass was an important component of above-ground biomass throughout the time sequence. Aboveground saw palmetto rhizomes were a major biomass category. Nutrient concentrations in live aboveground biomass did not appear to change with time since fire and were similar to those in other shrublands. Biomass pools of major nutrients frequently equaled or exceeded those in the soil, but wetter sites had more organic matter and nutrients in the soil. Atmospheric deposition of N, P, Ca, Mg, and K was low compared to biomass pools. Retention of nutrients in soils and regrowing vegetation after fire may be important to the persistence of scrub on low nutrient soils.