**AWARDS ISSUED PRIOR TO JANUARY 20, 2025, WERE FUNDED UNDER PREVIOUS ADMINISTRATIONS AND MAY NOT REFLECT THE PRIORITIES AND POLICIES OF THE CURRENT ADMINISTRATION.** CROP DIVERSIFICATION OFFERS A GREAT OPPORTUNITY FOR ACHIEVING FOOD SECURITY WITHOUT COMPROMISING OUR ENVIRONMENT. CROP ROTATION AND COVER CROPPING ARE TWO EFFECTIVE STRATEGIES TO ACHIEVE INCREASED DIVERSIFICATION IN AGRICULTURAL SYSTEMS. DESPITE THIS IMPORTANCE, WE DON'T HAVE A CLEAR UNDERSTANDING OF HOW TWO-WAY DIVERSIFICATION OF CASH CROPS AND COVER CROPS OPTIMIZE SOIL BIOGEOCHEMICAL PROCESSES THAT SUPPORT ECOSYSTEM SERVICES INCLUDING PRODUCTIVITY, SOIL HEALTH, AND SOIL'S RESILIENCE TO CLIMATE EXTREMES. THEREFORE, WE PROPOSE TO INVESTIGATE THE POTENTIAL OF THIS TWO-WAY DIVERSIFICATION IN THE SOUTHEAST U.S., AN UNDER-REPRESENTED REGION WITH MARGINAL SOILS AND WARMER CLIMATE. SPECIFICALLY, THE PROPOSED PROJECT WILL QUANTIFY THE EFFECTS OF SINGLE, DOUBLE AND MULTI-SPECIES COVER CROPS ON SIMPLIFIED TO DIVERSIFIED CROPPING SYSTEMS INCLUDING CORN MONOCULTURE, SOYBEAN MONOCULTURE, CORN-SOYBEAN ROTATION, AND CORN-SOYBEAN-COTTON ROTATION ON (I) SOIL HEALTH, (II) SOIL BIODIVERSITY WITH PARTICULAR EMPHASIS TO ARBUSCULAR MYCORRHIZAL FUNGI, (III) AGRONOMIC OUTCOME, AND (IV) SOIL RESILIENCE TO CLIMATE EXTREMES. IN ADDITION, WE WILL INTEGRATE THE KNOWLEDGE GENERATED INTO EXTENSION PROGRAMS TO IMPROVE PRODUCERS' AWARENESS AND ADOPTION OF CROP DIVERSIFICATION.THE EXPECTED OUTCOME IS TO OPTIMIZE THE EXTENT OF DIVERSIFICATION OF BOTH CASH AND COVER CROPS TO SUPPORT SOIL HEALTH AND RESILIENCE, AND CROP PRODUCTIVITY IN THE WARM AND HUMID REGIONS OF SOUTHEAST U.S.