Dados do Trabalho

Título

FIRE EFFECTS ON MINERALOGY AND SOIL ORGANIC MATTER QUANTITY AND QUALITY IN TWO DIFFERENT TEMPERATE RAINFOREST SOILS

Resumo

Fires have increased frequently and affected areas in recent years, mainly affecting topsoil. The fire effects can occur even at low severity, depending on the heating period and the soil minerals, making the predictions site-specific and challenging to escalate in a broader context. An experiment was performed to test the effect of different fire intensities on two different temperate rainforest soils (Andisol and Inceptisol) under controlled conditions. The objective was to evaluate the fire effect on the amount and composition of soil organic matter (SOM) and the role of different mineralogy on soil organic carbon (SOC). The soils were heated at 300-600-900 °C in a muffle for 20 minutes. Physics, chemical, thermogravimetric (TGA), and X-Ray Diffraction (XRD) analyses were performed. The most significant changes in physicochemical properties on both soils occur in moderately and highly intense fires (600 to 900 °C), increasing soil pH, nutrient availability, and decreasing soil water repellency. TGA showed higher ash content in the Inceptisol. The energy release was higher in the Andisol than in the Inceptisol due to more aromatic compounds in the Inceptisol. Clay changes were evident with the loss of kaolinite and gibbsite in the Inceptisol burned at 600°C and 900°C. SOM and mineralogy changes indicate the soil's resistance to warming. Even though the same type of forest is researched, warming at different intensities shows varying effects on the SOC and mineralogy of the different soils.  

Palavras-chave

nutrients, mineralogy, wildfires, soil organic carbon, biogeochemical cycles

Instituição financiadora

Fondecyt 1220716 - Anillo ACT210060 - ANID-Beca 21231535

Agradecimentos

Earthshape Project - Programa de Doctorado en Ciencias de los Recursos Naturales-UFRO