Tom Craven Matt Simon Anne Trainor

 Construct a RHESSys ecohydrologic model for Sandhills Region

Sandhills Eight-County Area. Shown on a blue to red color ramp is an 20 foot elevation model of the region. Dashed black lines indicate primary roads, blue lines - major hydrology. Ft. Bragg (right) and Camp Mackall (left) boundaries are shown in fuchsia.

 Sub-basin – Cape Fear 14, Part of the Cape Fear River Basin

The entire sub-basin was processed using Arc Hydro in ArcGIS 9.2 using a LiDAR-derived digital elevation model (DEM) created from the North Carolina Floodplain Mapping Program (NCFMP) by the North Carolina Department of Transportation (NCDOT This DEM has a 20 ft spatial resolution or roughly 6 meters.

Reclassified LULC from 15 to 4 classes – Hardwood Deciduous Forest Shrub/Scrub Woody Wetlands – Evergreen Evergreen Forest Mixed Forest – Open/Barren Developed (open space, low and medium intensity) Barren – Herbaceous Grassland Herbaceous Cultivated Crops Emergent Herbaceous Wetlands Open Water

Land Use Type30 m pixelsPercentageCumulative % Evergreen Forest % Grassland/Herbaceous %67.98% Barren Land (Rock/Sand/Clay) %82.91% Woody Wetlands - Deciduous %90.72% Developed, Open Space %96.06% Developed, Low Intensity %97.27% Deciduous Forest %98.35% Mixed Forest %99.38% Shrub/Scrub %99.88% Cultivated Crops120.05%99.93% Emergent Herbaceous Wetlands60.03%99.96% Open Water60.03%99.98% Developed, Medium Intensity40.02%100.00% Totals %

 Arcview (Arc2World) to construct world file  Template File Parameters  Single Soil Type: Sandy Loam  Land use: Undeveloped  4 Vegetation Types from 30 m LULC  Topography  DEM, Hill slope, Wetness index, Slope, Aspect  Patch Identification  Composite of hill slope, wetness index and LULC  Trial 1: 4,161 discrete patch ids Raster calculator: LULC + WI*100 + hill slope *  Trial 2: 91 discrete patch ids Raster calculator: LULC + WI*10

 Get the model running  Incorporate variation in soil types and depths  Use explicit routing to examine hydrologic connectivity

 Add option to write a logfile with state variables  Examine templates and create worldfiles in class for the example watershed  Initial gray areas  Exact method for creation of useful grids  Headers in.def files  Going from scratch was difficult but yields a better understanding of the inner workings