A Geomorphic and Ecological Analysis of Using Mosses for Controlling Stream Bank Erosion

Western Illinois University, Macomb IL

Investigators

Abstract

This research project will examine the degree to which mosses may serve as an alternative for stream bank stabilization in environments where there has been limited success by other riparian vegetation. Stream bank erosion often results in the loss of valuable land resources and a degradation of environmental quality because stream sediment and nutrient loads increase while water quality gets reduced. Stream bank erosion also affects infrastructure, such as roads, bridges, and buildings, by impacting their very foundations. Riparian vegetation plays both hydrological and mechanical functions on stream banks by increasing the tensile strength of soils and intercepting surface runoff and precipitation to potentially reduce bank failure. Perennial herbs and woody plants, including shrubs, are the two major vegetation types that traditionally have been used to help control stream bank erosion, because their deep root systems promote bank stability and reduce the rates of bank erosion. This project will evaluate the ecological condition of mosses and their effects on soil characteristics and bank erosion in different experimental settings. Project findings will provide new perspectives regarding how the presence or absence of moss carpets affects soil pressure and consequently the rates of bank erosion. The project will contribute new understanding about integrated relationships among fluvial geomorphology, riparian vegetation, ecosystem restoration, and biogeomorphology. Project results will provide information and insights that will assist decision makers, governmental agencies, and resource managers in adopting effective and sustainable approaches to stream bank stabilization. They also will be useful to those engaged in restoration activities by providing perspectives about alternative approaches to stabilize stream banks. The investigators will focus on analysis of the effectiveness of mosses for stream bank stabilization through a comparative analysis for study areas in the Chesapeake Bay and Upper Mississippi River watersheds. They will analyze biogeomorphic relationships and feedbacks between mosses and stream banks through a series of in situ and laboratory experiments over a three-year time frame. The experiments will survey multiple sites using terrestrial LiDAR, traditional geomorphic methods, and bioecological techniques. Geospatial data for the study areas, including digital elevation models (DEMs), satellite imagery, stream network, and land cover, will be integrated with information from field surveys for a detailed biogeomorphic analysis. Project findings will provide new perspectives about stream bank stabilization projects and the understanding of relationships between riparian vegetation and fluvial geomorphology for similar environmental conditions.