Grantee Research Project Results
2005 Progress Report: Linking Watershed Characteristics with Flow Regime and Geomorphic Context to Diagnose Water Quality Impairment at Multiple Spatiotemporal Scales
EPA Grant Number: R831367Title: Linking Watershed Characteristics with Flow Regime and Geomorphic Context to Diagnose Water Quality Impairment at Multiple Spatiotemporal Scales
Investigators: Poff, N. LeRoy
Current Investigators: Poff, N. LeRoy , Bledsoe, Brian P. , Dean, Denis
Institution: Colorado State University
EPA Project Officer: Packard, Benjamin H
Project Period: November 1, 2003 through October 31, 2007
Project Period Covered by this Report: November 1, 2004 through October 31, 2005
Project Amount: $897,798
RFA: Development of Watershed Classification Systems for Diagnosis of Biological Impairment in Watersheds and Their Receiving Water Bodies (2003) RFA Text | Recipients Lists
Research Category: Watersheds , Water
Objective:
The objectives of the research project are to: (1) quantify interactions between watershed characteristics, flow regime components, and geomorphic settings that explain variation in sediment and biological indicators of water quality impairment in Environmental Monitoring and Assessment Program (EMAP) datasets; (2) create a national classification of water quality impairment in terms of flow regime components and land use; and (3) regionally test flow regime-water quality linkages by conducting field studies in Rocky Mountain streams.
Progress Summary:
We completed data analysis for our fall 2004 field experiment (Objective 3) aimed toward isolating the independent and interactive effects of streamflow reduction and fine sediment deposition on biotic condition. We examined the response of 14 measures of macroinvertebrate community structure and function (as defined by species traits). We analyzed the data using an information-theoretic approach to model selection to determine the relative contributions of four factors (Flow, Fine Sediment, Flow-Fine Sediment Interaction, and Flow x Flow) to each of these 14 community attributes. Model selection results showed greatest support for an additive effect between reduced flow and fine sediment deposition for several measures of biotic condition; however, there was also some evidence to suggest that these two stressors interact synergistically in some cases, with fine sediments causing a greater decline in biotic condition at higher flow velocities than at lower flow velocities. The results from this study will contribute toward the refinement of biological indicators used to detect water quality impairment caused by fine sediment deposition and reductions in streamflow.
We also completed field sampling for a natural experiment aimed toward quantifying the effects of reductions in baseflow on stream geomorphic and biological condition. We sampled stream reaches above and below 14 diversion structures in summer and fall of 2005. These streams varied in the proportion of flow diverted from the stream channel, ranging from 0.1-99 percent flow removed. We collected streamflow data and detailed measurements of physical habitat at 8 transects in each reach. We measured channel and bankfull widths, thalweg depth and velocity, and mapped geomorphic units along each transect. We also determined particle-size distributions and areal coverage by fine sediments by doing a 400-pebble grid count in each reach. We collected macroinvertebrates from six locations (three fast-velocity and three slow-velocity) and measured depth, velocity, and percent of fine sediments at each sampling location. We will analyze these data by contrasting undiverted reaches with diverted reaches in the same stream and will relate changes in biotic condition to changes in habitat using multiple regression and multivariate approaches. These data will be analyzed in FY 2006.
We also made substantial progress on Objectives 1 and 2 in 2004-2005 with regard to database compilation and development of novel modeling tools for predicting streamflow regimes and geomorphic context at EMAP sites across the western United States. These activities are summarized below:
- Completed compilation and integration of several nationwide geospatial datasets including geology, land cover, climate, reservoirs, and all 10-m digital elevation models (DEMs) available for the conterminous United States in preparation for large-scale hydrologic modeling with artificial neural networks.
- Compiled a large set of U.S. Geological Survey (USGS) daily gauge data for four large hydrologic regions of the United States and delineated watershed boundaries for each gauge location. Determined extent of landuse/landcover and hydrologic change in these regions.
- Performed an inter-region comparison of landuse/landcover and streamflow gauge availability by watershed scale (Strahler stream order) to assess the potential for modeling ungauged, wadeable streams in various regions of the United States.
- Developed new GIS-based metrics for predicting floodplain presence and extent using 10 m DEMs. Expanded modeling capability by developing an algorithm to characterize valley context (entrenchment, slope, floodplain width, and hillslope connectivity) and similar geomorphic metrics on a stream network scale.
- Applied and tested a regional hydrologic regime classification to insect assemblages in the Pacific Northwest and identified associations with several types of hydrologic metrics (low flows and high flows).
- Developed and tested GIS-based tools for predicting stream morphologic types. In initial testing for the Pacific Northwest, these models correctly predicted channel type with 76 percent accuracy using only widely available geospatial data and without reliance on field survey data.
- Developed and tested two empirical models for predicting median substrate size across entire drainage networks. Testing in mountainous ecoregions of the Pacific Northwest suggests that these models (which include both hydrologic and geomorphic predictors) are more accurate than previously published models based solely on geomorphic characteristics.
- Developed an along-stream network function for automated statistical analysis of various drainage network characteristics.
- Developed and tested a new algorithm for automated watershed delineation and hydrologic analysis that rectifies biomonitoring site locations to appropriate watershed outlet locations in DEMs.
Future Activities:
We will analyze data from the diversion gradient experiment and present these results at the 2006 North American Benthological Society meeting and will prepare a manuscript reporting our findings. We also are compiling all EMAP biological data for analysis in conjunction with the GIS-generated physical data. We plan to complete development of artificial neural network (ANN) models for predicting streamflow regimes at ungauged EMAP sites and quantifying departures from least disturbed hydrologic conditions across the western United States in 2006. After the ANN models are tested and verified with USGS gauge data, model predictions will be used to develop a classification of hydrologic alteration and to examine associations between departures from least disturbed hydrologic conditions and stream biota at western EMAP sites.
Journal Articles on this Report : 5 Displayed | Download in RIS Format
Other project views: | All 47 publications | 15 publications in selected types | All 13 journal articles |
---|
Type | Citation | ||
---|---|---|---|
|
Flores AN, Bledsoe BP, Cuhaciyan CO, Wohl EE. Channel-reach morphology dependence on energy, scale, and hydroclimatic processes with implications for prediction using geospatial data. Water Resources Research 2006;42:W06412, doi:10.1029/2005WR004226. |
R831367 (2005) R831367 (2006) R831367 (Final) |
Exit |
|
Olden JD, Poff NL, Bledsoe BP. Incorporating ecological knowledge into ecoinformatics: an example of modeling hierarchically structured aquatic communities with neural networks. Ecological Informatics 2006;1(1):33-42. |
R831367 (2005) R831367 (2006) R831367 (Final) |
Exit Exit |
|
Poff NL, Olden JD, Pepin DM, Bledsoe BP. Placing global stream flow variability in geographic and geomorphic contexts. River Research and Applications 2006;22(2):149-166. |
R831367 (2005) R831367 (2006) R831367 (Final) |
Exit Exit |
|
Poff NL, Bledsoe BP, Cuhaciyan CO. Hydrologic variation with land use across the contiguous United States: geomorphic and ecological consequences for stream ecosystems. Geomorphology 2006;79(3-4):264-285. |
R831367 (2005) R831367 (2006) R831367 (Final) |
Exit Exit |
|
Wohl E, Angermeier PL, Bledsoe B, Kondolf GM, MacDonnell L, Merritt DM, Palmer MA, Poff NL, Tarboton D. River restoration. Water Resources Research 2005;41:W10301, doi:10.1029/2005WR003985. |
R831367 (2005) R831367 (2006) R831367 (Final) |
Exit |
Supplemental Keywords:
watershed classification, hydrologic impairment, water quality, hydrologic modeling, stream ecology, fluvial geomorphology,, RFA, Scientific Discipline, Water, Water & Watershed, Hydrology, Environmental Monitoring, Ecology and Ecosystems, Watersheds, ecosystem modeling, watershed classification, hydrogeomorphic categories, geomorphic, GIS, water quality, spatial & temporal scalingProgress and Final Reports:
Original AbstractThe perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.