** AWARDS ISSUED PRIOR TO JANUARY 20, 2025, WERE FUNDED UNDER PREVIOUS ADMINISTRATIONS AND MAY NOT REFLECT THE PRIORITIES AND POLICIES OF THE CURRENT ADMINISTRATION.** HISTOSOLS ARE A TYPE OF SOIL CREATED FROM THE ACCUMULATION OF LARGE AMOUNTS OF DEAD PLANT LITTER OVER TIME, RESULTING IN DARK-COLORED, CARBON-RICH, SOIL ORGANIC MATTER. THESE SOILS SERVE AN IMPORTANT ROLE IN STORING GLOBAL CARBON BELOWGROUND, PROTECTING IT FROM BEING RELEASED INTO THE ATMOSPHERE WHERE IT CAN CONTRIBUTE TO CLIMATE CHANGE. HOWEVER, SOME HISTOSOLS ARE INTENSIVELY DRAINED FOR AGRICULTURAL PRODUCTION, CAUSING THE SOIL TO BRAKE-DOWN AND BE CONVERTED INTO CARBON DIOXIDE GAS. THIS IS BOTH A THREAT TO THE HEALTH AND SUSTAINABILITY OF THE AGROECOSYSTEM AND A SOURCE OF GREENHOUSE GASES. THIS PROJECT AIMS TO EVALUATE A POSSIBLE NEW BEST MANAGEMENT PRACTICE THAT COULD BE USED BY GROWERS TO REDUCE THE RATE OF SOIL BREAK-DOWN IN DRAINED HISTOSOLS, WHILE ALSO ENHANCING CARBON STORAGE. WE WILL SCIENTIFICALLY EVALUATE THE POTENTIAL FOR FINE SEDIMENTS (SILTS AND CLAYS) TO BE ADDED TO CULTIVATED HISTOSOLS AS AN AMENDMENT TO SLOW THE LOSS OF SOIL THROUGH THE CREATION OF A PROTECTIVE CHEMICAL BOND BETWEEN THE SEDIMENT AND THE SOIL ORGANIC MATTER, REFERRED TO AS MINERAL-ASSOCIATED ORGANIC MATTER (MAOM). SPECIFICALLY, THIS PROJECT WILL: (1) DETERMINE THE CURRENT AMOUNT OF MAOM IN A CULTIVATED HISTOSOL, (2) TEST THE TYPE AND AMOUNT OF SEDIMENT AMENDMENT NEEDED, HOW IT IS AFFECTED BY FLOODING, AND THE CONSEQUENCE TO SOIL HEALTH IN LABORATORY EXPERIMENTS, AND (3) TEST THE AMENDMENT IN AN OUTDOOR EXPERIMENT WITH PLANTED SUGAR CANE. THROUGH THESE STUDIES, OUR RESEARCH WILL ADVANCE THE SCIENTIFIC UNDERSTANDING OF MAOM FORMATION IN HISTOSOLS AND HELP TO INFORM THE POTENTIAL USE OF FINE SEDIMENT AMENDMENTS BY GROWERS TO IMPROVE THE SOIL HEALTH, RESILIENCE, AND SUSTAINABILITY OF HIGH ORGANIC MATTER AGRICULTURAL FIELDS.