Dune Dynamics & Management

Coastal dunes are natural and nature-based features that act as the first line of defense against oceanside flooding, and have been recognized as a viable & sustainable option to moderate coastal hazards. Consequently, coastal communities are increasingly constructing artificial dunes and/or encouraging growth of natural dunes to improve coastal protection. However, the response of natural & constructed dunes to storm impacts varies greatly, even over short spatial scales (i.e., tens of meters).

Current Studies

Internal structure of coastal dunes

Overview: The high spatial variability of dune response to storms may be due, in part, to complex feedbacks between sediment, dune vegetation, and overall morphology—not all of which can be replicated in managed coastal systems. Specifically, constructed dunes lack the complex internal ecologic & sedimentologic structure that develops in natural systems from slow and intermittent aeolian deposition and episodic erosion. These complex ecogeomorphic feedbacks & their implications for coastal management are at the core of this project. This research relies on the combination of field observations & numerical modeling to assess the trade-offs between natural dune dynamics and the instant flood protection services provided by a constructed dune. This project seeks to 1) document the internal structure of coastal dunes subjected to various management approaches; 2) quantify the role of internal structure in altering the style and rate of storm-induced erosion; and 3) develop trade-off curves that identify timescales at which naturally developed dunes exceed the protective services of constructed dune.

The role of beach nourishment in dune growth

Overview: In response to beach & dune erosion, many coastal communities elect to “nourish” their beaches with sand from offshore reservoirs for added protection. We are leveraging relationships with our management partners to study the effect of beach nourishment on dune dynamics during a joint (i.e., multi-town) beach nourishment planned for summer 2022. Specifically, we aim to 1) track sediment fluxes post-nourishment spatially and temporally; and 2) identify local factors that hinder or accelerate sediment transport & deposition processes.

Collaborators: Nicholas Cohn (US Army Corps of Engineers Engineer Research and Development Center), Julie Zinnert & the Coastal Plant Ecology Lab at Virginia Commonwealth University

Funding Sources: USACE ERDC Flood & Coastal Systems R&D Program Resilience of Coastal Dunes; NOAA Ecological Effects of Sea Level Rise program

Media

VIMS Write-Up: https://www.vims.edu/newsandevents/topstories/2019/hein_dune.php

Daily Press: https://www.dailypress.com/news/dp-nw-vims-dune-study-20191013-ewdzs7h2tvfntoogmnre4bxjcq-story.html

Publications

Please feel free to contact us for pdf copies of any of the following publications. Note: * - Coastal Geology Lab student author

*Davis, E.H., Hein, C.J., Cohn, N., Zinnert, J., White, A., 2024. Differences in internal sedimentologic and biotic structure between natural, managed, and constructed coastal foredunes, Geomorphology. doi: 10.1016/j.geomorph.2024.109083.

*Heminway, S.S., Cohn, N., *Davis, E.H., White, A., Hein, C.J., Zinnert, J.C., 2024. Exploring Ecological, Morphological, and Environmental Controls on Coastal Foredune Evolution at Annual Scales Using a Process-Based Model. Sustainability, 16, 3460. doi: 10.3390/su16083460.

*Heminway, S.S., *Davis, E.H., Cohn, N., Skaden, J., Anderson, D., Hein, C.J., 2023. Modeled changes in foredune morphology influenced by variable storm intensity and sea-level rise, In: Coastal Sediments ’23, Proceedings of the 13^th International Symposium on Coastal Engineering and Science of Coastal Sediment Processes, World Scientific Publishing Co., Singapore, p. 684-697, doi: 10.1142/9789811275135_0064

*Davis, E.H., Cohn, N., *Heminway, S.S., Skaden, J., Hein, C.J., 2023. Linking internal coastal foredune moisture dynamics to erosion vulnerability, In: Coastal Sediments ’23, Proceedings of the 13^th International Symposium on Coastal Engineering and Science of Coastal Sediment Processes, World Scientific Publishing Co., Singapore, p. 656-669, doi: 10.1142/9789811275135_0062

Abstracts & Presentations

Feel free to contact us for pdf copies of any of the following abstracts or their associated presentations or posters. Note: * - student author

*Davis, E.H., Hein, C.J., Cohn, N., White, D., Zinnert, J.C., Hein, E.A., 2021. Morphostratigraphic Differences Between Natural, Managed, and Constructed Coastal Foredunes. Abstract ID #891481, American Geophysical Union Fall Meeting, New Orleans, LA, USA.

*Davis, E.H., Hein, C.J., Cohn, N., White, D., Zinnert, J.C., Hein, E.A., 2021. Coupled ecologic and sedimentologic controls on coastal foredune resilience to storm impacts Abstract ID #9482, Coastal and Estuarine Research Federation (CERF), virtual.

Cohn, N., White, D., *Davis, E.H., Goldstein, E., Zinnert, J.C., Hein, C.J., 2021. “Alongshore variable coastal foredune responses: de-coupling morphologic, ecological, and anthropogenic controls” Abstract ID #, CERF, virtual.

White, D., Ramos, K., Cohn, N., *Davis, E.H., Goeke, M.E., Hein, C.J., Zinnert, J.C., 2021. “Patterns and characteristics of belowground biomass distribution across natural and managed coastal foredunes” Abstract ID #9387, CERF, virtual.

White, D., Ramos, K., Cohn, N., *Davis, E.H., Goeke, M.E., Hein, C.J., Zinnert, J.C., 2021 “Belowground differences in the biotic structure of natural and unmanaged coastal foredunes” Abstract ID #93950, Ecological Society of America, virtual.