**AWARDS ISSUED PRIOR TO JANUARY 20, 2025, WERE FUNDED UNDER PREVIOUS ADMINISTRATIONS AND MAY NOT REFLECT THE PRIORITIES AND POLICIES OF THE CURRENT ADMINISTRATION.** SYNCHRONIZING CROP N DEMAND WITH SOIL N SUPPLY CONTINUES TO CHALLENGE AGROECOSYSTEM SUSTAINABILITY. COMPLEX INTERACTIONS BETWEEN BIOCHEMICAL AND PHYSICAL COMPONENTS OF SOIL ORGANIC MATTER CYCLING HAVE RESULTED IN SUBSTANTIAL UNCERTAINTY IN PREDICTING SOIL N SUPPLY. INCREASINGLY, SOIL MINERAL COMPOSITION IS RECOGNIZED TO INFLUENCE BOTH THESE COMPONENTS OF N CYCLING, YET MECHANISMS ARE UNDERSTUDIED AND DISCONNECTED FROM AGROECOSYSTEM OUTCOMES. MOREOVER, THE ABILITY OF CURRENT SOIL HEALTH METRICS TO ACCURATELY DESCRIBE THESE DYNAMICS ACROSS DIFFERING SOIL MINERALOGICAL CONTEXTS IS NOT WELL UNDERSTOOD. THESE GAPS IN UNDERSTANDING PREVENT THE PRESCRIPTION AND IMPLEMENTATION OF EFFICIENT N MANAGEMENT. THIS PROJECT SEEKS TO CLOSE THOSE GAPS BY DETERMINING THE EXTENT TO WHICH SOIL MINERALOGY INFLUENCES SOIL N AVAILABILITY AND RELATED SOIL HEALTH MEASUREMENTS. BY LEVERAGING LONG-TERM NO-TILL SITES (>15 YEARS) ACROSS THE BREADTH OF MINERALOGICAL CONTEXTS IN THE UNITED STATES, WE WILL QUANTIFY THE RELATIVE IMPORTANCE AND DIRECTIONALITY OF MINERALOGICALLY MEDIATED CONTROLS ON N INPUT FATE AND AVAILABILITY TO CROPS. ADDITIONALLY, WE WILL INTEGRATE USDA-RECOMMENDED SOIL HEALTH METRICS INTO AN N MANAGEMENT FRAMEWORK BY ACCOUNTING FOR SITE-SPECIFIC SOIL MINERALOGICAL CONTEXT. THIS WORK WILL SUPPORT THE PROGRAM AREA GOALS BY IMPROVING THE SUSTAINABILITY OF AGROECOSYSTEM MANAGEMENT AND WILL SUPPORT THE PRIORITY AREA GOALS BY ADVANCING UNDERSTANDING OF BASIC BIOGEOCHEMICAL PROCESSES WHILE CONTEXTUALIZING GROWER DECISION SUPPORT TOOLS (I.E. SOIL HEALTH INDICATORS). PROJECT FINDINGS ARE ANTICIPATED TO HELP EXPLAIN WHY AND PREDICT HOW SOIL N SUPPLY DIFFERS ACROSS CONTEXTS WHILE DISTINGUISHING WHICH SOIL HEALTH INDICATORS CAN BE USED BY RESEARCHERS AND PRODUCERS TO BEST CAPTURE THESE PROCESSES AND OUTCOMES.

University Of Missouri System, Columbia MO

Investigators