Mineralogy functionality and microbial community structure post-fire in temperaterain forest ecosyst

Karla Erazo Mora, Francisco Matus, Ignacio Jofré, Felipe Aburto, José Dörner, Paola Durán, Michaela Dippold, Carolina Merino.

Abstract

Fire is a central natural disturbance in forest ecosystems such as temperate rainforests of southern Chile regulating the carbon (C) balance in these ecosystems but due to climate change this disturbance has increased in frequency and area burned. These forests have a high C sequestration capacity. Most temperate rain forest soils stand in soils of volcanic origin with a high phosphate retention capacity (>85%) and a high soil organic matter (SOM) content, where more than 40% of this is complexed with metals such as Fe, Mn and Al in the soil matrix. Other important soils are derived from intrusive rocks like granodiorite and metamorphic origin, also with high SOM and Fe contents, but with lower pHs. During fire events, surface clay can dehydrate, and can collapse losing their physicochemical properties as allophanic soils. Wildfire alters the physical, chemical, and biological properties that modify soil porosity and greenhouse gas (GHG) emissions. The study of microbial communities, litter decomposition, humidity-oxygen fluctuation, enzymatic activity, clay mineralogy, and soil organic C (SOC) provides information on SOM changes, representing one of the most important components affected by wildfire. Therefore, it is essential to know the magnitude and directions of these changes and the impact on biogeochemical cycles.

Presented in 8th International Workshop Advances in Science and Technology of Bioresources, CHILE