**AWARDS ISSUED PRIOR TO JANUARY 20, 2025, WERE FUNDED UNDER PREVIOUS ADMINISTRATIONS AND MAY NOT REFLECT THE PRIORITIES AND POLICIES OF THE CURRENT ADMINISTRATION.** THIS POSTDOCTORAL RESEARCH PROPOSAL (A7201), ENTITLED MICROBIAL DYNAMICS GOVERNING CARBON STORAGE IN THE COVER CROP ROOT ZONE, ADDRESSES THE BIOENERGY, NATURAL RESOURCES, AND ENVIRONMENT (BNRE) AFRI PRIORITY AREA AND SOIL HEALTH PROGRAM FOCUS (A1401), WHICH ENCOMPASSES BASIC AND APPLIED RESEARCH ON SOIL BIOGEOCHEMICAL FUNCTIONS THAT CONTRIBUTE TO BUILDING RESILIENT AGRICULTURAL SYSTEMS. SOIL ORGANIC MATTER (SOM) IS AN EMERGING ECOSYSTEM PROPERTY THAT PROMOTES CARBON SEQUESTRATION ON AGRICULTURAL LANDSCAPES AND CONTRIBUTES TO SOIL HEALTH BY ACTING AS A RESERVOIR FOR NUTRIENTS. PLANTING COVER CROPS IS A COMMON STRATEGY TO IMPROVE SOIL HEALTH AND SEQUESTER CARBON BUT DOES NOT RELIABLY OR PREDICTABLY INCREASE SOM. SOM FORMATION IS LIKELY DRIVEN BY PLANT-MICROBE INTERACTIONS IN THE ROOT ZONE THAT AFFECT CARBON METABOLISM, BUT THESE MECHANISMS REMAIN UNEXPLORED. THE OVERARCHING GOAL OF THIS PROPOSAL IS THE PROBE THE ROLE OF ROOT-MICROBE INTERACTIONS DRIVING SOM IN TWO AGRONOMICALLY IMPORTANT COVER CROPS. THE WORK DESCRIBED HERE WILL BE UNDERTAKEN AT CORNELL UNIVERSITY BY THE PD, MARIE SCHAEDEL, AND SUPPORTED BY PRIMARY MENTOR DR. DANIEL BUCKLEY AND COLLABORATING MENTOR DR. LAURIE DRINKWATER. IN ADDITION TO BUILDING A FOUNDATIONAL UNDERSTANDING OF MICROBE-MEDIATED SOM CYCLING IN COVER CROPS, THIS POSTDOCTORAL RESEARCH PROGRAM WILL PROVIDE ESSENTIAL TRAINING AND SKILLS THAT WILL ENABLE THE PD TO ACHIEVE CAREER INDEPENDENCE IN AN ACADEMIC FIELD. MENTORSHIP AND PROFESSIONAL DEVELOPMENT EXPERIENCES AT CORNELL UNIVERSITY WILL ENABLE THE PD TO BECOME A LEADER EQUIPPED TO ADDRESS CRITICAL CHALLENGES TO SUSTAINABLE AGRICULTURAL INTENSIFICATION BY LEVERAGING KNOWLEDGE OF SOIL MICROBIAL PROCESSES.