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Functional Linkage of Water Basins and Streams: FLoWS v1 ArcGIS tools. David Theobald, John Norman, Erin Peterson Natural Resource Ecology Lab, Dept of Recreation & Tourism, Colorado State University Fort Collins, CO 80523 USA 17 May 2006. Project context.
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Functional Linkage of Water Basins and Streams: FLoWS v1 ArcGIS tools David Theobald, John Norman, Erin Peterson Natural Resource Ecology Lab, Dept of Recreation & Tourism, Colorado State University Fort Collins, CO 80523 USA 17 May 2006
Project context • Challenges of STARMAP (EPA STAR): • Addressing science needs Clean Water Act • Integrate science with states/tribes needs • Develop landscape-based indicators to assist in testing tenable hypotheses generated using understanding of ecological processes
Premise Challenges to develop improved landscape-scale indicators (Fausch et al. 2002; Gergel et al. 2002; Allan 2004) are: - clearer representation of watersheds & hierarchical relationship; - incorporate nonlinearities of condition among different watersheds and along a stream segment Need to characterize spatial heterogeneity & scaling of watersheds when developing indicators of biological condition Goal: to develop indicators that more closely represent our understanding of how ecological processes are operating
From watersheds/catchments as hierarchical, overlapping regions… River continuum concept (Vannote et al. 1980)
“Lumped” or watershed-based analyses • % agricultural, % urban (e.g., ATtILA) • Average road density (Bolstad and Swank) • Dam density (Moyle and Randall 1998) • Road length w/in riparian zone (Arya 1999) • But ~45% of HUCs are not watersheds EPA. 1997. An ecological assessment of the US Mid-Atlantic Region: A landscape atlas. EPA ATtILA 2002.
… to network of catchments Network Dynamics Hypothesis - Benda et al. BioScience 2004
Reaches linked to catchments • 1 to 1 relationship • Properties of the watershed can be linked to network for accumulation operation
Covariates: landscape context • Co-variate(s) at spatial location, site context - E.g., geology, elevation, population density at a point • Co-variate(s) within some distance of a location - Housing density at multiple scales • Watershed-based variables - Proportion of urbanized area • Spatial relationships between locations - Euclidean (as the crow flies) distance between points - Euclidean (as the fish swims) hydrologic network distance between points • Functional interaction between locations - Directed process (flow direction), anisotropic, multiple scales - How to develop spatial weights matrix? - Not symmetric, stationary violate traditional geostatistical assumptions!?
USGS NHD, NED
USGS NHD, NED
“true” catchments “adjoint” catchments Segments Pre-processingGenerating reach contributing areas (RCAs) Automated delineation • Inputs: • stream network (from USGS NHD or other) • topography (USGS NED, 30 m) Processes: • 1. traditional WATERSHED command requires FILLed DEM – “hydro-conditioned” • 2. Cost-distance using Topographic Wetness & Position Indices
Generating RCAs: FILLed 1.) Filled DEM 2.) Flow Direction
Generating RCAs: cost-distance 1.) DEM
2.) Topographic Wetness Index 3.) Topographic Position Index
Generating RCAs 4) Stream Reaches 5.) RCAs (Yellow)
a b c Evaluation of RCAs • “Truth” • Hand-delineated from 1:24K • Modeled (1:100K, 30 m DEM): • A. traditional (FILL-ing) • B. cost-distance • Measure: Jaccard’s similarity coefficient: • b / (a + b + c)
Preliminary results Cost-distance RCAs Mean accuracy: 85% FILLed DEM 50 m/WATERSHED Mean accuracy: 78%
Within RCA hydro-weighting Instream flow (hydro network distance to outlet) Overland flow (hydro distance to stream)
Landscape Network Landscape network features and associated relationships table From graph theory perspective, reaches are nodes, confluences are edges
Selections • User-defined field • Polylines or RCAs • Cumulative (distance from selected feature)
Estimated discharge • Average annual precipitation & temperature, basin area • Vogel et al. 1999 Vogel
Export to distance matrices Instream distance Straight-line
Distance matrices (cont.) Downstream only Upstream only
Distance matrices (cont.) Proportion upstream Proportion downstream
Distance matrices (cont.) Downstream portion dist only Number of confluences
Summary • River Continuum to Network • From overlapping waterbasins to network spatial structure • Open • Simple data structure • Python linked to GeoProcessing object • Non-GIS (thru Access, SQL, etc.) • Flexible • User-defined variables to accumulate, navigate network • Different selection sets, combinations • Compute framework once, use with many point configurations (samples) • Robust • Flow-based vs. Strahler stream order • Cost-weighted methods • Developed, tested (broken), refined • E.g, Mid-Atlantic Highlands; Oregon; Central Shortgrass Prairie; Alaska;
Next steps • Project/tool website: • www.nrel.colostate.edu/projects/starmap • FLoWS, FunConn, RRQRR • FLoWS database to complement tools • Attach additional attributes to FLoWS database • Land cover (urban, ag, “natural”) • Historical, current, future housing density • Hydro & slope weighted road density • Human accessibility • Within reach/segment • Streams as 2D features
SCALE: Grain Landscape River Network Microhabitat Microhabitat COARSE Climate Atmospheric deposition Geology Topography Soil Type Network Connectivity Stream Network Nested Watersheds Connectivity Flow Direction Network Configuration Drainage Density Confluence Density Vegetation Type Basin Shape/Size Land Use Topography Segment Contributing Area Segment Tributary Size Differences Network Geometry Localized Disturbances Land Use/ Land Cover Reach Riparian Zone Riparian Vegetation Type & Condition Floodplain / Valley Floor Width Cross Sectional Area Channel Slope, Bed Materials Large Woody Debris Overhanging Vegetation Substrate FINE Biotic Condition, Substrate Type, Overlapping Vegetation Detritus, Macrophytes Shading Detritus Inputs Biotic Condition Terrestrial Aquatic Peterson 2005
CR - 829095 Thanks! • Comments? Questions? • Thanks to K. Verdin at USGS EROS Data Center for sharing EDNA datasets • Funding/Disclaimer: The work reported here was developed under the STAR Research Assistance Agreement CR-829095 awarded by the U.S. Environmental Protection Agency (EPA) to Colorado State University. This presentation has not been formally reviewed by EPA. The views expressed here are solely those of the presenter and STARMAP, the Program (s)he represents. EPA does not endorse any products or commercial services mentioned in this presentation. • FLoWS: www.nrel.colostate.edu/projects/starmap • davet@nrel.colostate.edu
Water basin - Stream Process/Functional Zonal Accumulate Up/down (net.) Watershed HUCs/WBD Reach Contributing Areas (RCAs) Grain (Resolution)