** AWARDS ISSUED PRIOR TO JANUARY 20, 2025, WERE FUNDED UNDER PREVIOUS ADMINISTRATIONS AND MAY NOT REFLECT THE PRIORITIES AND POLICIES OF THE CURRENT ADMINISTRATION.** PHOSPHORUS (P) IS A KEY NUTRIENT FOR PLANT PRODUCTION AND CAN BE SUPPLEMENTED EITHER THROUGH SYNTHETIC FERTILIZER OR ANIMAL WASTE. OVERUSE OF P IN AGRICULTURE HAS DEPLETED RESERVES AS WELL AS BUILT-UP P IN SOILS AND DETERIORATED WATER QUALITY. THIS INTEGRATED PROJECT AIMS TO DEVELOP DUAL-FUNCTION BIOCHAR (DUO-BIOCHAR) THAT WILL CAPTURE EXCESS P FROM AGRICULTURAL FIELDS AND ACT AS A SLOW-RELEASE P FERTILIZER. THE EFFICACY OF DUO-BIOCHAR WILL BE MEASURED IN GREENHOUSE AND FIELD STUDIES USING WINTER WHEAT AND RYEGRASS MODEL CROPS. THE PROPOSED RESEARCH WILL FOCUS ON FIVE OBJECTIVES: 1) DEVELOP DUO-BIOCHAR WITH FUNCTIONALIZATION OF SURFACE AND INTERNAL PORE NETWORKS TO ABSORB AND CO-PRECIPITATE P AND FINE-TUNE SLOW-RELEASE PROPERTIES, 2) DEVELOP A FUNDAMENTAL UNDERSTANDING OF SURFACE AND INTERFACIAL CHEMISTRIES OF DUO-BIOCHAR AND CORRELATE WITH THE FORM, COMPOSITION, AND CONTENT OF P; 3) OPTIMIZE P RELEASE EFFICIENCY OF THE DUO-BIOCHAR TO A MODEL AGRONOMIC CROP; 4) ASSESS ON-FARM ECONOMICBENEFITS OF USING BIOCHAR IN THE PARTICIPATING STATES; AND 5) DEVELOP EDUCATIONAL MATERIALS/RESOURCES AND FIELDS ACTIVITIES TO IMPROVE KNOWLEDGE ON DUO-BIOCHAR. OUTCOMES OF THIS RESEARCH EFFORT WILL PROVIDE FOUR COMPREHENSIVE AGRONOMIC AND ENVIRONMENTAL BENEFITS: I) RETAIN EXCESS P IN SOILS, THEREBY PROTECTING P LOSS FROM MANURE-LADEN SOILS, II) ACT AS A SLOW-RELEASE FERTILIZER TO PROVIDE SUFFICIENT P TO PLANTS WHEN NEEDED MOST DURING THE MID AND LATE GROWTH STAGES, III) IMPROVE SOIL QUALITY, AND IV) PROTECT WATERBODIES FROM EXCESS P-RELATED EFFECTS. THIS IS A TRANSATLANTIC COLLABORATIVE PROJECT AMONG INSTITUTES FROM THE U.S, THE REPUBLIC OF IRELAND, AND NORTHERN IRELAND.