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A presentation I gave at Utah Valley University in February of 2020 that details results from an analysis of how land cover change and hydrologic alteration have affected exposed sediment extent in Grand Canyon

Slides from a presentation I gave at the 2019 AGU Fall Meeting in Washington, D.C.

A presentation I gave at the 14th Biennial Conference of Science and Management on the Colorado Plateau and Southwest Region in Flagstaff, Arizona.

A poster that describes the methodology and results of an approach for automatically interpreting the geomorphic processes driving landscape change across large spatial areas.

A poster detailing a potion of my PhD research that was presented at the 2015 fall meeting of AGU in San Francisco.

Braided channels arise due to high sediment availability in conjunction with regular competent flows and readily erodible banks. Together, these boundary conditions lead to the deposition and reworking of a network of transient bars that characterize the braided planform. However, quantifying the geomorphic response of braided systems to alterations in these boundary conditions is not straightforward, as channels adjust over a wide range of timescales, rendering traditional field-based observation intractable. As such, the development of simple yet robust relationships between channel morphology and sediment transport has the potential to allow predictions of channel response to altered hydrologic or sediment regimes. In this research, I first use laboratory flume experiments to relate particle travel distance during floods (termed particle path length) and the spacing of channel bars in braided rivers (Chapter 2), finding that deposition sites for sediment in transport can be readily predicted by the characteristic confluence-diffluence spacing in a reach. I then use the relationship between path length and channel morphology to build a simple, open-source morphodynamic model for braided rivers that computes sediment transport using path-length distributions derived from bar spacing (Chapter 3). I explore the validity of this model, specifically noting that its modular framework allows exploration of process representations in morphodynamic modeling in ways existing models do not. Finally, I employ the model to determine the role of sediment supply in braided channel bar morphodynamics (Chapter 4). Specifically, I address the relative roles of sediment sourced from upstream versus sediment sourced from within a braided reach in terms of channel morphodynamics at decadal timescales. This research demonstrates that simple scaling relationships, while necessarily imperfect, nevertheless provide insight into morphodynamic processes in braided rivers, while also allowing predictions of channel response to sediment or hydrologic forcing at the timescales of channel adjustment.

This is a preprint of a chapter of Alan Kasprak's Ph.D. dissertation in preparation for submission to Geology.

The slides from my PhD defense seminar, given September 4th 2015 at Utah State University

The slides from my PhD defense seminar, given September 4th 2015 at Utah State University

Hough-Snee, N. et al., (eight authors). 2014. Riparian vegetation and instream wood dynamics in streams of the interior Columbia River basin. Society of American Foresters Intermountain Meeting, Logan, UT.

A poster documeting five years of geomorphic change on the River Feshie, Scotland. Details the methods for capturing the morphodynamic signatures of several braiding mechansisms from successive annual GPS and lidar surveys of the river.

A report detailing the application of the River Styles Framework to three streams in the John Day River Watershed, Oregon. Report may help researchers in linking reach-scale channel morphology and salmonid habitat.

A poster that details a comparison of four channel classification frameworks as applied in a physiographically-diverse basin of the Pacific Northwest. Implications for determining channel condition and prioritizing restoration activities are also discussed.

Environmental drivers of instream wood: models from the Columbia RIver Basin, USA. Poster presented at the 2014 Joint Aquatic Sciences Meeting, Portland, OR.

A poster documented the results of TLS scanning on a 3 km reach of the braided River Feshie, Scotland.

A presentation at the 2010 AGU Fall Meeting detailing part of my MS work, which developed a rapid and extensive method for delineating sources of large woody debris to New England streams using airborne lidar.