HR: 1330h
AN: H42E-1127    [PDF]
TI: Mapping Stream Hydrogeomorphic and Disturbance Regimes Throughout Drainage Networks
AU: * Cuhaciyan, C O
EM: fluvial@engr.colostate.edu
AF: Colorado State University, Campus Delivery 1320 Colorado State University, Fort Collins, CO 80523-1320 United States
AU: Sanborn, S
EM: ssanborn@engr.colostate.edu
AF: Colorado State University, Campus Delivery 1320 Colorado State University, Fort Collins, CO 80523-1320 United States
AU: Bledsoe, B P
EM: bbledsoe@engr.colostate.edu
AF: Colorado State University, Campus Delivery 1320 Colorado State University, Fort Collins, CO 80523-1320 United States
AB: Hydrologic regimes and geomorphic characteristics interact to create and alter the spatial and temporal distribution of aquatic habitats in drainage networks. We present an approach for mapping stream hydrogeomorphic types and disturbance regimes at the drainage network scale using geospatial data. We selected stream gauges of relatively high quality and long-term record to develop models for predicting membership of ungauged sites into ecological disturbance classes. Cluster analysis is used to group streams with similar disturbance regimes using significant, non-redundant streamflow characteristics. Different suites of metrics are used to represent disturbance and derive multiple sets of disturbance classes. Average frequencies and durations of hydrologic disturbance for each class are then computed to facilitate interpretation. Discriminant analysis is used to characterize the disturbance regime of ungauged sites using geologic, topographic, climatic and other watershed attributes. All of the watershed metrics used are computed from remotely sensed data using a GIS. Geomorphic characterization of each stream link is performed using previously developed models based, in part, on 10m digital elevation models to compute metrics including slope, stream power (SA$^{0.4}$) and substrate size. The models of disturbance regime and geomorphic context are then combined to map the hydrogeomorphic disturbance type of each stream link within an entire watershed. Two watersheds on the west slope of the Cascades in Washington are used to illustrate and test the approach. Predictions for stream links with USGS gauging stations are compared to disturbance metrics calculated directly from streamflow gauge data. The ability to identify stream hydrogeomorphic types and disturbance characteristics from readily available digital geospatial data can improve methods for stratifying aquatic habitats within ecoregions to more effectively explain patterns of biological variation and facilitate understanding of linkages between biotic and hydrogeomorphic diversity.
DE: 1824 Geomorphology (1625)
DE: 1848 Networks
DE: 1860 Runoff and streamflow
SC: Hydrology [H]
MN: 2003 Fall Meeting