Jiarui Lei, Yinghao Zhang, Rachel Schaefer
Aquatic vegetation provides many natural benefits, including the protection of shorelines from storms and erosion, the provision of habitat, and the improvement of water quality. Waves can kick up sediment from the bed causing erosion, making the water cloudy and adding pollutants to the water. Vegetation reduces wave motion and keeps sediment from being kicked up. However, this benefit of vegetation cannot be incorporated into lake and coastal management plans, because there is no accurate method for predicting the reduction of wave motion by natural, flexible vegetation, such as freshwater eelgrass Vallisneria americana and the seagrass Zostera marina. This project will develop a model for predicting the reduction of wave energy from flexible vegetation based on the characteristic of the vegetation, including geometry, size and flexibility. In addition, the project will develop models for predicting the velocity threshold for resuspension and the impact of vegetation on this threshold. Combining the two models, engineers and watershed managers will be able to assess different scenarios of vegetation restoration for their potential to protect shorelines and to reduce resuspension events that drive poor water quality.
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