FARMERS ARE UNDER PRESSURE TO INCREASE NITROGEN USE EFFICIENCY AND REDUCE NITRATE LEACHING TOGROUNDWATER UNDER INTENSIVE AGRICULTURAL PRODUCTION, BUT MEASUREMENT OF NITRATE LEACHING FLUX TOGROUNDWATER IS CUMBERSOME AND EXPENSIVE. THERE IS AN URGENT NEED TO DEVELOP COST-EFFECTIVE TOOLSFOR MONITORING NITRATE LEACHING FOR ON-FARM ASSESSMENT, TESTING EFFECTS OF MANAGEMENT, ANDIMPROVING NUTRIENT TRANSPORT AND BIOGEOCHEMICAL MODELS. OUR MAJOR GOAL IS TO COMBINEAFFORDABLE MULTI-FUNCTIONAL MULTI-DEPTH SOIL SENSORS AND SOIL PROCESS MODELS FOR REAL-TIME IN SITUNITRATE LEACHING MONITORING AND WATER QUANTITY AND QUALITY MANAGEMENT. WE WILL ACHIEVE THEPROJECT GOAL WITH FOUR SPECIFIC AIMS: 1) DESIGN AND TEST OF FULLY PRINTABLE MULTI-FUNCTIONAL SOILSENSORS IN THE LAB; 2) ASSEMBLE SENSORS INTO A MULTI-DEPTH (0-1.1 M) SENSING SYSTEM FOR IN SITU REAL-TIMENITRATE LEACHING MONITORING; 3) USE SENSOR MEASUREMENTS TO EVALUATE THREE PROCESS MODELS FORNITRATE LEACHING MODELING; 4) ENHANCE THE UNDERSTANDING AND ADOPTION OF AFFORDABLE SENSOR-MODELFUSION APPROACH THROUGH EDUCATION AND EXTENSION ACTIVITIES.PROJECT OUTPUTS WILL GUIDE STAKEHOLDERS TO USE COST-EFFECTIVESENSORS FOR IRRIGATION, FERTILIZATION, AND MANURE APPLICATION TO IMPROVE AGRICULTURAL PRODUCTIVITY ANDREDUCING ENVIRONMENTAL POLLUTION.