TEMPORAL CHANGES IN THE SOIL MICROBIOME IN RESPONSE TO CLIMATE CHANGE DRIVERS

We used the B4WarmED open-air climate system to explore the effects of warming on the temperate boreal ecotone microbiome in a controlled experiment. This northern Minnesota experiment was established in spring 2008 and comprises two upland forested sites in Cloquet and Ely. The sites are 150 miles apart and the Local climates for both the sites are broadly similar. Local soil is primarily sandy loam, with roughly 10% clay at each site; per USDA soil taxonomy, most CFC soil is classified as Inceptisols, and HWRC as Entisols. B4WarmED features on-site datalogging of hourly precipitation, above- and below-ground temperatures, and other pertinent environmental traits, including volumetric soil moisture. We collected soil samples from 2010-2020 one time per year from an unmodified control condition with no temperature elevation; a warming condition elevated by 1.8C; and a second warming condition elevated by 3.4C. The warming treatment condition were maintained during April-November field seasons with combined above- and belowground heating elements with real-time feedback. We extracted the DNA and perform 16S rDNA analysis using amplicon sequencing using 515f-806r primers.