Category: Ecological Research
Title: Effect of a Prescribed Burn in Ponderosa Pine on Inorganic Nitrogen Concentrations of Mineral Soil
Author: Ryan, M.G., * Covington, W.W.
Subject: Fire ecology, Nutrient cycling, Soil, Prescribed burns
Abstract: Soil inorganic nitrogen was measured during the summer after a fall prescribed burn at a ponderosa pine site in northern Arizona. Fire behavior varied among sawtimber, pole, and sapling stands; the greatest fuel reduction occurred in the sawtimber. Ammoniumnitrogen content of the upper 15 cm of soil in the burned sawtimber plots was as much as 80 times greater than in unburned plots. This is approximately 70 kg ha-1 more available N, a major fertilizing effect. The soil under the burned pole plots had a slightly greater inorganic nitrogen content than under unburned plots, while burning did not change the soil inorganic nitrogen in the sapling plots. The increased availability of nitrogen after burning may affect regeneration, understory growth, and growth of overstory trees.
Source: USDA Forest Service
Publisher: USDA Forest Service, Rocky Mountain Research Station