AGRICULTURAL ACTIVITIES MAY PRODUCE AN IMPORTANT IMPACT ON THE ENVIRONMENT. IT IS THEREFORE ESSENTIAL TO KNOW BETTER THIS EFFECT AND TAKE MEASURES TO CONTROL IT, AS IT IS HEREBY ADDRESSED, IN ORDER TO PURSUE THE FOLLOWING GOALS: I) GET TO KNOW, FOR FOUR EXPERIMENTAL AGRICULTURAL WATERSHEDS IN NAVARRA, THE CHARACTERISTICS AND PROPERTIES OF WATERS GENERATED FROM THEM AND THE EFFECTS OF AGRICULTURAL ACTIVITIES ON WATERS BY ASSESSING POSSIBLE ENVIRONMENTAL CONSEQUENCES, ESPECIALLY THOSE RELATED TO NITRATES AND PHOSPHATES, AND BY IDENTIFYING THE ELEMENTS THAT CONTROL THE DYNAMICS ON THE ANALYSED SUBSTANCES (SULPHATES, CARBONATES, POTASSIUM, CALCIUM, MAGNESIUM AND SODIUM, APART FROM THE ABOVE MENTIONED); II) DEFINE AND EXPLAIN THE DIFFERENT BEHAVIOURS OBSERVED IN THE CATCHMENTS AND EVALUATE THE IMPORTANCE OF DISSOLVED SUBSTANCES VS SOLIDS (LOADS); III) DELVE INTO THE KNOWLEDGE OF FACTORS THAT DETERMINE GULLY EROSION, WITH FOCUS ON EDAPHIC ELEMENTS; V) EVALUATE THE ANNAGNPS MODEL WITH ADVANCED TECHNIQUES IN ORDER TO SIMULATE GULLY EROSION EMPHASIZING IN THE EDAPHIC ELEMENTS, TOGETHER WITH COLLEAGUES FROM THE USDA, AND ANALYSING SCENARIOS AND HYPOTHESIS OF INTEREST FOR OUR CONDITIONS; VI) INVESTIGATE THE SPATIAL DISTRIBUTION OF THE BED MACRO-ROUGHNESS ON RILL EROSION, EXPLORING ITS CONSEQUENCES, PARTICULARLY ON MODELLING; VII) ASSESS THE IMPORTANCE OF GULLY EROSION IN NAVARRA; VIII) EVALUATE SEVERAL MODELS (ANNAGNPS, SWAT, TOPLATS) TO EXPLORE THEIR APPLICABILITY IN RAIN FED CATCHMENTS IN NAVARRA USING LEADING TECHNIQUES AND FOCUSING (WHERE APPLICABLE) ON NITRATES AND PHOSPHATE SIMULATIONS AND VINEYARDS EROSION; IX) USE ANNAGNPS SIMULATION MODEL, ONCE CALIBRATED IN AN EXPERIMENTAL WATERSHED, AS A MANAGEMENT TOOL IN ELORZ RIVER BASIN (282KM2) AS REFERRING TO WATER, SEDIMENTS AND WATER QUALITY (N AND P) TOGETHER WITH THE GOVERNMENT OF NAVARRE (ANALYSE OF SCENARIOS, SUSTAINABLE AND ECONOMICALLY OPTIMAL MANAGEMENT AND USES AND CONTRASTING CONSEQUENCES OF APPLYING CODES OF GOOD PRACTICE, ETC.); X) IDENTIFY KEY ELEMENTS IN THE CONNECTIVITY OF RAIN FED AGRICULTURAL WATERSHEDS BY OBSERVING AND MAPPING THE SURFACE WITH HIGH RESOLUTION IMAGES FROM DRONES, ANALYSING SEDIMENT CONCENTRATION VERSUS WATER DISCHARGE HYSTERESIS LOOPS, MEASURING THE HILLSLOPE RUN-OFF THROUGH DOZENS OF GUTTERS ON THE FLOOR, THE SPREAD OF RARE EARTH ELEMENTS AND FOLLOWING DETECTION DOWNSTREAM, USING SIMULATION MODELS AND ANALYSING THE ROLE OF CONCENTRATED FLOWS IN CONNECTIVITY. WE RELY ON, AMONG MANY OTHER ELEMENTS: THE INVALUABLE DATA BASE COLLECTED FROM FIVE EXPERIMENTAL AGRICULTURAL WATERSHEDS IN NAVARRA, LOCATED IN DIFFERENT ENVIRONMENTS AND INCLUDING IRRIGATED LANDS; AND THE UNIQUE STRUCTURE OF THE CHANNEL FOR HYDRO-ENVIRONMENTAL STUDIES ON SOILS AT THE INSTITUTE FOR SUSTAINABLE AGRICULTURE (CORDOBA) (CSIC). FROM OUR POINT OF VIEW, THIS PROJECT WOULD PERFECTLY FIT UNDER GOAL N. 2 OF SPANISH STRATEGY OF SCIENCE, TECHNOLOGY AND INNOVATION: �FOOD SAFETY AND QUALITY; PRODUCTIVE AND SUSTAINABLE AGRICULTURE, SUSTAINABILITY OF NATURAL RESOURCES, MARINE AND MARITIME RESEARCH�.