Effect of fire severity and presence of bamboo (Chusquea culeou) on soil chemical properties in Andean Patagonian forests of Argentina

Background Fire is recurrent in Patagonian forests of Argentina, and is frequently associated with the die-off of bamboo (Chusquea culeou). Fire induces changes in soil properties, which may affect vegetation recovery. Aims This study assesses how fire severity affects soil chemical properties in different Patagonian forests, in the absence and presence of C. culeou. Methods We collected samples from the upper 5 cm of mineral soil from 44 plots distributed in five forest types affected by low-severity and high-severity fire, and unburned areas. Half of the plots also had C. culeou. Key results Fire severity affected soil pH, organic matter, electrical conductivity, nitrogen, C:N ratio, and cation exchange capacity. Changes in organic matter and C:N ratio varied among forest type, and variations in pH and sodium were detected among forest types. The presence of C. culeou affected soil pH, C:N ratio, and calcium. Conclusions The changes recorded were expected and could have a lasting effect on long-term productivity. Nothofagus pumilio and Nothofagus antarctica, and forests with C. culeou, varied in their soil chemical properties, sometimes regardless of fire. Implications Considering the heterogeneity of vegetation and soil in postfire environments is vital for predicting possible successional trajectories and defining restoration objectives.