The blurred line between form and process: a comparison of stream classification frameworks
- Published
- Accepted
- Subject Areas
- Aquaculture, Fisheries and Fish Science, Biogeography, Ecology, Ecosystem Science, Environmental Sciences
- Keywords
- Stream classification, Natural Channel Design, watershed monitoring, River Styles, John Day Watershed, Fluvial geomorphology, Watershed planning, Stream processes, Columbia River Basin
- Copyright
- © 2015 Kasprak et al.
- Licence
- This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, reproduction and adaptation in any medium and for any purpose provided that it is properly attributed. For attribution, the original author(s), title, publication source (PeerJ PrePrints) and either DOI or URL of the article must be cited.
- Cite this article
- 2015. The blurred line between form and process: a comparison of stream classification frameworks. PeerJ PrePrints 3:e885v2 https://doi.org/10.7287/peerj.preprints.885v2
Abstract
Stream classification provides a means to understand the diversity and distribution of channels and floodplains that occur across a landscape while drawing linkages between geomorphic form and process. Accordingly, stream classification is frequently employed as a watershed planning, management, and restoration tool. At the same time, there has been intense debate and criticism of particular frameworks, on the grounds that these frameworks classify stream reaches based largely on their physical form, rather than direct measurements of the hydrogeomorphic processes operating therein. Despite this critical debate surrounding stream classifications, and their ongoing use in applied watershed management, direct comparisons of channel classification frameworks are rare. Here we apply four classification frameworks that contain a range of form- and process-based methods within a watershed of high conservation interest in the Columbia River Basin, U.S.A. We compare the results of the River Styles Framework, Natural Channel Classification, Rosgen Classification System, and a channel form-based statistical classification at 33 field-monitored sites. For stream network-based frameworks (Natural Channel Classification and River Styles) we compare classification outputs across the entire Middle Fork John Day Watershed. We found that the four frameworks consistently classified reach types into similar groups based on each reach or segment’s dominant hydrogeomorphic elements. Where divergence in classified channel types occurred, differences can be attributed to the (a) spatial scale of input data used, (b) the requisite metrics and their order in completing a framework’s decision tree and/or (c) whether the framework attempts to classify current or historic channel form. The relative agreement between frameworks indicates that criticism of classification based simply on whether a classification contains form-based measurements, devalues each framework’s relative merits. These form-based criticisms may also ignore the geomorphic tenet that channel form reflects formative hydrogeomorphic processes across a given landscape.
Author Comment
This manuscript was submitted to and subsequently declined at Water Resources Research (WRR). We have incorporated WRR's reviewers' suggestions and the manuscript is currently formatted for submission to PLOS ONE.