USDA-ARS Southwest Watershed Research Center Mission Sound Science for Watershed Decisions To develop knowledge and technology to conserve water and soil in semi-arid lands ARS Watershed Locations Selected Accomplishments from Walnut Gulch Precipitation Analyses Flood Frequency Transmission Losses Hydrologic Instrumentation Erosion and Sediment Transport Developing Natural Resource Simulation Models Data and Data Access Scope of the research unit Facilities Main office - Tucson 8 scientists, 3 support scientists, 20 Staff Field office - Tombstone 3 Field Technicians Experimental Watersheds Walnut Gulch Santa Rita Experimental Range
Walnut Gulch Experimental Watershed Grassland Brush Tombstone 0 2 4 6 8 10 Kilometers Hydrology Watershed models & decision support systems AGWA for watershed management and assessments Remote sensing to better parameterize models Semiarid water, carbon and energy balance Land-atmosphere exchange of CO2 and water flux Remote Sensing for Soil Moisture and Roughness Remote sensing and micrometeorological techniques combined for ET and CO2 fluxes. Satellite-based rainfall totals Urban-rural interface Ephemeral stream channel recharge Variability in infiltration due to urbanization Erosion and Sediment Rates and Processes Understanding Erosion Processes in Rangelands Channel Geomorphology and Processes Tracers to identify Source Areas and Processes Conservation Practices Small Rock and other Structures Conservation Effects Assessment Project Rangelands Models and Tools Rangeland Hydrology and Erosion Model Linking Satellite data to model input Economic returns of conservation Using remote sensing to estimate rangeland productivity - RANGES 10 watersheds 2-150 km 2 Evaluate the effects of channel network, spatial distribution of rainfall Event Hydrographs Flume 6 Runoff - Large Watersheds Runoff - Unit Source Area 10 watersheds.2-4.4 ha Evaluate the effects of soil, vegetation, rainfall intensity Event hydrographs Flume 103 Developing Natural Resource Simulation Models WEPP - Water Erosion Prediction Project KINEROS - Kinematic Erosion and Runoff Model EPIC - Erosion Productivity Impact Calculator CREAMS - Chemicals, Runoff, and Erosion from Agricultural Management Systems RUSLE Revised Universal Soil Loss Equation AGWA Geospatial Interface for SWAT & KINEROS RHEM Rangeland Hydrology and Erosion Model
Conservation Effects Assessment Project (CEAP) The purpose of CEAP is to quantify the environmental benefits of conservation practices implemented under the 2002 Farm Bill (retrospective analysis). Tracking these benefits over time will allow policy-makers and program managers to implement and modify existing programs to more effectively and efficiently meet goals (prospective analysis). The CEAP Project has Two Major Components and Reporting Scales National assessment - provides estimates of conservation benefits at the national scale Ecosystem assessment - provides detailed assessments of ecosystem goods and services in regional watersheds Reynolds Creek Grazing Land CEAP Proposed Timeline Fluxes Micrometeorological and ecophysiological techniques are used better understand and quantify ecosystem energy, water and carbon dioxide exchanges in order to: -quantify riparian water use and improve basin surface and ground water budgets -understand the interactions between CO 2 and water cycles in semiarid regions -determine the ecohydrologic consequences of woody plant encroachment Walnut Gulch Rangelands Shrub - Tree 2007 Rangelands Grass - Crops 2009 Pasture - Introduced Grass 2008 Improved Quantification of Semiarid Water Budget Components Rangeland Soil Conservation Research water control berms To quantify the impacts of conservation practices on: sediment retention soil moisture vegetation With respect to: design landscape position rainfall/runoff loose rock dams
Runoff and Erosion Processes Partial Area Response Spatial Heterogeneity Variable intensity (25-180 mm/hr) Small (0.75 m 2 ) and Large (2x6 m) plots Providing new fundamental knowledge on rangeland hydrologic response and erosion processes Infiltration and Runoff Steady state infiltration increases with rainfall intensity Erosion Partial area response raindrop detachment, deposition Entire area response potential flow detachment and continuous transport Semi-arid grassland, shrub, and oak woodland sites State and Transition models Grazing and Fire Runoff and Erosion infiltration rate (mm/hr) 120 100 80 60 40 20 0 0 50 100 150 200 Undisturbed Disturbed qs (g/s) 8 6 4 2 0 Undisturbed Fire Heavy grazing rainfall rate (mm/hr) 0.0 0.2 0.4 0.6 0.8 1.0 contributing area Improved Watershed Modeling Capabilities Urban-rural interface element combinations of various runoff run-on combinations The AGWA (Automated Geospatial Watershed Assessment) Tool Surface Water Hydrologic Modeling Incorporation of Remotely Sensed and GIS Data into Hydro Models Improved modeling of water quality and Best Management Practices (BMP s) Integration of Research with Elected Officials and Decision Makers The AGWA delineation of buffer strip BMP model elements in KINEROS2 AGWA Automated Geospatial Watershed Assessment Tool AGWA requires commonly available spatial data that describe an area s topography, soils, and land cover to perform watershed analyses Automatically prepares complex input files for two hydrologic models, SWAT & KINEROS. Provides visualization of landscapes & model results (interactive) Useful for management scenarios, identifying sensitive regions, & decision support AGWA is a cooperative effort with the US-EPA Remote Sensing Surface Soil Moisture (m 3 / m 3 in top 5 cm) Walnut Gulch boundary Surface Soil Moisture Value High : 0.4 Vegetation Temperature Soil Surface Roughness Soil Moisture & Water Deficit Index CO 2 Fluxes Dr. Moran Low : 0.0 Rahman et al. 2005
Net Daytime CO 2 Flux (g m -2 (12 h) -1 ) 9/30/92 9/17/93 From WDI (vegetation & temperature), calculations of instantaneous fluxes, and daily flux measurements < 0 0 1.99 2 3.99 4 5.99 6 7.99 8 9.99 10 11.99 12 13.99 14 15.99 16 17.99 18 19.99 > 20 g m -2 (12 hrs) -1 Methods: Cesium 137 and Rare Earth Element Tracers S Lucky Hills, WG Shrub Area 8/30/98 9/26/99 Holifield et al. 2004 Other Projects Upper San Pedro Partnership Conservation Effects Assessment Project (CEAP) Western Rangelands China Urbanization, and Vegetation Upper San Pedro Partnership (USPP) USPP Goal: Assuring an adequate long-term groundwater supply is available to meet the reasonable needs of both, the areas residents and property owners (current and future) and the San Pedro National Riparian Conservation Area
Upper San Pedro Partnership This effort is a step beyond the traditional science-stakeholder form of interaction to that of a true partnership where research is planned and conducted specifically to meet the needs of decision makers and resource managers