**AWARDS ISSUED PRIOR TO JANUARY 20, 2025, WERE FUNDED UNDER PREVIOUS ADMINISTRATIONS AND MAY NOT REFLECT THE PRIORITIES AND POLICIES OF THE CURRENT ADMINISTRATION.** AS GLOBAL SEA LEVELS RISE, LOW-LYING COASTAL LANDS ARE SUBJECT TO SHALLOW COASTAL FLOODING AND SALTWATER INTRUSION (SWI) AFFECTING THE PRODUCTIVITY OF FARMLANDS WORLDWIDE. THE NORTH AMERICAN COASTAL PLAIN, AND THE CHESAPEAKE BAY REGION, IN PARTICULAR, ARE EXPERIENCING RATES OF SEA LEVEL RISE TWICE THE GLOBAL AVERAGE. SWI REDUCES SOIL QUALITY, CROP PRODUCTIVITY, AND INCREASES THE MOBILITY OF NITROGEN AND PHOSPHORUS INTO LOCAL WATERWAYS. OUR PROJECT DIRECTLY ADDRESSES THIS CHALLENGE AREA'S GOALS BY DETERMINING POTENTIAL ADAPTATION STRATEGIES FOR MANAGING CLIMATE-INDUCED SWI RISK AND BY EXAMINING BIOPHYSICAL, SOCIO-ECONOMIC, AND POLICY DRIVERS OF RISKS AND RESILIENCIES IN AGROECOSYSTEMS EXPERIENCING CLIMATE CHANGE AND VARIABILITY. SPECIFICALLY, OUR RESEARCH WILL (1) INVESTIGATE FARMER LAND USE RESPONSE TO SWI AND ECONOMIC AND POLICY FACTORS AFFECTING ADAPTATION DECISIONS; (2) DETERMINE THE EFFECT OF SWI ON PRODUCTIVITY AND SURVIVAL OF CROP AND NON-CROP SPECIES; (3) IDENTIFY BIOGEOCHEMICAL CHANGES THAT ACCOMPANY SWI AND THEIR IMPACT ON WATER QUALITY; AND (4) EXAMINE TRADEOFFS AMONG ECONOMIC AND ENVIRONMENTAL OUTCOMES FROM ADAPTATION CHOICES TO DETERMINE HOW POLICIES MAY ENHANCE AGRICULTURAL SUSTAINABILITY. OUR EXTENSION PORTFOLIO WILL (1) PROVIDE USER-DRIVEN, SCIENCE-BASED SOLUTIONS TO FARMERS EXPERIENCING SWI; (2) DEVELOP AN EXTENSION EDUCATION MODULE TO BE USED IN REGIONAL PROGRAMS, COMMODITY BOARD MEETINGS, AND TRADE SHOWS TO EDUCATE FARMERS ON HOW TO MANAGE SWI; (3) ENGAGE WITH MID-ATLANTIC EXTENSION EDUCATORS THROUGH TRAIN-THE-TRAINER EVENTS TO HELP THEM IDENTIFY SWI AND MANAGE RISK. WE WILL COMBINE EXTENSION ACTIVITIES, FIELD TRIALS, GREENHOUSE EXPERIMENTS, EMPIRICAL LANDCOVER ANALYSIS, AND BIOECONOMIC ANALYSIS TO JOINTLY ENHANCE AGRICULTURAL PRODUCTIVITY, FARM PROFITABILITY, AND ENVIRONMENTAL QUALITY.