** AWARDS ISSUED PRIOR TO JANUARY 20, 2025, WERE FUNDED UNDER PREVIOUS ADMINISTRATIONS AND MAY NOT REFLECT THE PRIORITIES AND POLICIES OF THE CURRENT ADMINISTRATION.** THE PREEMINENT CHALLENGE TO REDUCE SOIL DEGRADATION IS THE LACK OF ACCURATE AND WIDESPREAD DATA FOR ROBUST HEALTH ASSESSMENT. CONVENTIONAL SOIL SAMPLE COLLECTION AND LABORATORY ANALYSIS ARE LABOR-INTENSIVE, COSTLY, AND SLOW TO YIELD RESULTS. CONVERSELY, SPECTROSCOPY WHICH IS BASED ON THE INTERACTION OF ELECTROMAGNETIC SPECTRUM (OR LIGHT) WITH MATTER, IS A RAPID, NON-DESTRUCTIVE, AND LOW-COST METHOD WITH THE POTENTIAL FOR IN SITU SOIL HEALTH ESTIMATIONS. CURRENT LITERATURE LACKS A COMPLETE TECHNICAL ANALYSIS ON SOIL MOISTURE AND INTACTNESS EFFECTS ON ALL SPECTRAL REGIONS AND TECHNIQUES WHICH HAS CREATED A BARRIER FOR FIELD IMPLEMENTATION. THE GOAL OF THIS PROJECT IS TO ENABLE THE PRACTICAL APPLICATION OF SPECTROSCOPY FOR IN SITU SOIL HEALTH ASSESSMENT. TO THIS END, THREE OBJECTIVES ARE DEVISED: (I) INVESTIGATE DIFFERENT SPECTROSCOPIC TECHNIQUES FOR SOIL HEALTH ASSESSMENT, (II) STUDY THE EFFECTS OF SAMPLE CONDITION ON SOIL SPECTRA AND MITIGATION STRATEGIES, AND (III) DESIGN, DEVELOP, AND TEST AN INTEGRATED SPECTROSCOPIC SOIL SENSING SYSTEM (IS4) FOR IN SITU 3D MAPPING OF SOIL HEALTH PARAMETERS. THIS SENSOR PLATFORM WILL BE CAPABLE OF HIGH-THROUGHPUT, LOW-COST, RAPID, AND ACCURATE 3D SOIL HEALTH MEASUREMENTS TO SUPPORT DECISION MAKING ON CLIMATE-SMART MANAGEMENT PRACTICES AND TO SUPPORT RESEARCH TO UNDERSTAND MANAGEMENT OF PHYSICAL AND BIOGEOCHEMICAL PROCESSES.