Event Title

The Influence of Crew Variability when Using High Resolution Topographic Surveys to Monitor Instream Habitat: A Case Study from the Columbia River Basin

Presenter Information

Sara Bangen

Location

ECC 216

Event Website

http://water.usu.edu/

Start Date

4-3-2012 4:40 PM

End Date

4-3-2012 4:45 PM

Description

Worldwide, native fish species decline has resulted in efforts to protect and conserve imperiled populations. In the Columbia River basin alone Pacific salmonids are estimated at 10% of historic levels with 13 distinct populations federally listed as threatened or endangered. Knowledge of the status and trend of available habitat is fundamental to conserving these species. The Columbia Habitat Monitoring Program (CHaMP), piloted in 2011, conducts topographic surveys of sample stream reaches to provide spatially-explicit maps and snap-shots of habitat conditions. Like any monitoring campaign that might rely on data collected by different crews, distinguishing calculated differences that are a real signal from those simply due to noise is of critical importance. To better understand the influence of crew variability on topographically derived metrics and trends, an experiment was set up where seven crews sampled the same six sites. Analyses included identifying the magnitude and source of observed differences between crews, estimating spatially variable DEM errors using a Fuzzy Inference System (FIS), and modeling plausible geomorphic change detection (GCD) scenarios. Overall, the influence of crew variability on topographically-derived metrics was negligible. We observed some instances of substantial localized inter-crew elevation differences yet these could generally be attributed to a systematic error by a single crew and did not effect the overall distribution of DEM-derived metrics such as water depths. The surveys were of adequate quality to support change detection for both obvious changes and subtle changes along the channel margins. In the context of CHaMP and other monitoring programs using topographic surveying, observed results are encouraging as they imply that with minor protocol adjustments, improved training and better QA/QC measures, crew derived sources of error can be minimized.

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Apr 3rd, 4:40 PM Apr 3rd, 4:45 PM

The Influence of Crew Variability when Using High Resolution Topographic Surveys to Monitor Instream Habitat: A Case Study from the Columbia River Basin

ECC 216

Worldwide, native fish species decline has resulted in efforts to protect and conserve imperiled populations. In the Columbia River basin alone Pacific salmonids are estimated at 10% of historic levels with 13 distinct populations federally listed as threatened or endangered. Knowledge of the status and trend of available habitat is fundamental to conserving these species. The Columbia Habitat Monitoring Program (CHaMP), piloted in 2011, conducts topographic surveys of sample stream reaches to provide spatially-explicit maps and snap-shots of habitat conditions. Like any monitoring campaign that might rely on data collected by different crews, distinguishing calculated differences that are a real signal from those simply due to noise is of critical importance. To better understand the influence of crew variability on topographically derived metrics and trends, an experiment was set up where seven crews sampled the same six sites. Analyses included identifying the magnitude and source of observed differences between crews, estimating spatially variable DEM errors using a Fuzzy Inference System (FIS), and modeling plausible geomorphic change detection (GCD) scenarios. Overall, the influence of crew variability on topographically-derived metrics was negligible. We observed some instances of substantial localized inter-crew elevation differences yet these could generally be attributed to a systematic error by a single crew and did not effect the overall distribution of DEM-derived metrics such as water depths. The surveys were of adequate quality to support change detection for both obvious changes and subtle changes along the channel margins. In the context of CHaMP and other monitoring programs using topographic surveying, observed results are encouraging as they imply that with minor protocol adjustments, improved training and better QA/QC measures, crew derived sources of error can be minimized.

https://digitalcommons.usu.edu/runoff/2012/Posters/16