In depth variation of gypsifeorus forest soil properties after a controlled burn

Changes produced by fire on soils depends on several factors (vegetation, soil type, temperature, etc.). Here we study the influence of fire on a gypsiferous forest soil located northwest of the city of Zaragoza. Six blocks of undisturbed soil were collected and burned under laboratory conditions reaching 272.9 ± 21.7 oC at 1cm depth. The fire caused significant differences (p <0.05) in all studied parameters from the O horizon and in the first centimeter of the Ah horizon. No significant differences (p <0.05) for any parameters below this depth were observed. The O horizon, strongly hydrophobic, became hydrophilic after burning. Burning induced a loss of 3.14 Mg organic carbon/ha, less than half of the values reported for other soils with mollic horizon (8.3 Mg/ha). In our soil, the loss is due to a 53.8% in the O horizon by 35.8% in the first centimeter of the Ah, and only 10.4% is lost deeper.