FLOwPER v3 user’s guide supplement: Field application for collection of FLOw PERmanence field observations
No abstract available.
Report↗
Geology topics
Emily Dawn Heaston
Publications and source records attributed to Emily Dawn Heaston.
A streamflow permanence classification model for forested streams that explicitly accounts for uncertainty and extrapolation
Accurate mapping of headwater streams and their flow status has important implications for understanding and managing water resources and land uses. However, accurate information is rare, especially in rugged, forested terrain. We developed a streamflow permanence classification model for forested lands in western Oregon using the latest light detection and ranging-derived hydrography published in the National Hydrography Dataset. Models were trained using 2,518 flow/no flow field observations collected in late summer 2019–2021 across headwaters of 129 sub-watersheds. The final model, the Western Oregon WeT DRy model, used Random Forest and 13 environmental covariates for classifying every 5-m stream sub-reach across 426 sub-watersheds. The most important covariates were annual precipitation and drainage area. Model output included probabilities of late summer surface flow presence and were subsequently categorized into three streamflow permanence classes—Wet, Dry, and Ambiguous. Ambiguous denoted model probabilities and associated prediction intervals that extended over the 50% classification threshold between wet and dry. Model accuracy was 0.83 for sub-watersheds that contained training data and decreased to 0.67 for sub-watersheds that did not have observations of late summer surface flow. The model identified where predictions extrapolated beyond the domain characterized by the training data. The combination of spatially continuous estimates of late summer streamflow status along with uncertainty and extrapolation estimates provide critical information for strategic project planning and designing additional field data collection.
Oregon↗
Fishes of Harney Basin revisited: An assessment of the distribution of native and nonnative fishes over a half century
The Harney Basin is Oregon's largest internally draining basin and contains a unique native fish assemblage. The first and only comprehensive study of the origin and distribution of Harney Basin fishes occurred in 1971. Here, we update this study and identify potential threats to the basin's native fishes a half century later. Our assessment documents that all species of native fishes are still present, and with some exceptions distributed as originally reported. The distinctive fish assemblages in each of the 3 major subbasins within the Harney Basin (Silvies River, Silver Creek, and Donner und Blitzen River) support the hypothesis that terminal lakes in the Harney Basin (Malheur, Mud, and Harney Lakes) act as dispersal barriers, at least for native species. More than half of the fish species in the basin at present are introduced, primarily inhabiting low-elevation sites. We suggest that native non-salmonid species cohabiting these sites face the most immediate threats from climate change, water demands, and impacts from introduced fishes. Overall, our results show that native fish are still relatively widespread across the Harney Basin, but also face increasing threats despite the basin having experienced less development than many other areas in the Pacific Northwest. Improved understanding of the unique fishes of the Harney Basin, along with more detailed assessments of likely future trajectories of environmental risks are proactive measures that could improve conservation outcomes.
Oregon↗