2015 Undergraduate Research Day

Spring Water Assessment Network (SWAN), Springfield and Greene County, Missouri

Tyler Beeman and Beau Brummel
Ozarks Environmental and Water Resources Institute (OEWRI)
Faculty Advisor: Robert Pavlowsky

Spring discharges are important sources of water in areas of karst geology because they provide important ecological services to receiving water and reflect the overall quality of the local drinking supply. Potential sources of pollution in karst systems in both the rural and urban environment include point sources such as wastewater treatment plant outfalls, industrial waste discharges, poorly functioning onsite wastewater systems, as well as nonpoint sources from urban development and agricultural activities. This study reports on the preliminary results of the Spring Water Assessment Network (SWAN) involving three departments and two centers in the College for Natural and Applied Sciences. A total of 10 springs and 4 surface water sites that represent different land use characteristics within the recharge area within Springfield and outlying areas of Greene County were sampled for a variety of physical properties, chemicals, nutrients, and bacteria. We are interpreting water quality trends by assessing the spatial and seasonal variability of water quality at base flow and evaluating potential causes of water quality variations. This is a joint project with the Ozarks Environmental and Water Resources Institute and Center for Biological and Life Sciences (CBLS) with help from Dr. Paul Schweiger (BIO), GGP, and CHM.

Mining Influence on Lead Profiles in Historical Floodplain Deposits Along the Big River

Alison Keppel and March Owen
Ozarks Environmental and Water Resources Institute (OEWRI)
Faculty Advisor: Robert Pavlowsky

River floodplains function as sinks and sources of sediment in watersheds. In river systems affected by mining activities, floodplain soils can become contaminated with heavy metals by deposition and provide a long-term source of contamination as metal-rich sediment is released back to the channel by bank erosion. This study evaluates the concentration and spatial variability of floodplain contamination along Big River in southeast Missouri. The Big River drains the Old Lead Belt, a global leader in lead mining from 1900 to 1972. Sedimentological and geochemical analyses of floodplain deposits are used to demonstrate the long-term hazard of contamination in watersheds due to historical mining. A total of 18 cores were collected from a variety of floodplain elevations and ages of deposition ranging from 1 to 2 m deep. Concentrations of lead, zinc, inorganic/organic carbon, calcium and cesium-137 were used to determine stratigraphic relationships. The results reveal that floodplain deposits formed over the past 100 years are contaminated with lead concentrations >2,000 ppm. Lead concentrations in sediments deposited within the last 40 years have decreased to about 1,000 ppm after mine closure. Generally, Pb concentrations and depth of contamination decreases with elevation, lower flood frequency, and distance from the channel.

Spatial Distribution and Classification of Disturbance Zones in the James River, SW Missouri

Joe Nash and Marc Owen
Geography, Geology and Planning
Faculty Advisor: Robert Pavlowsky

Land use changes within a watershed can cause geomorphic responses in rivers such as bank erosion, sediment aggradation, and channel migration. The James River in the Ozarks region of Southwest Missouri has been affected by past and present agricultural practices and urban developments. To evaluate how the James River has responded over time, aerial photographs from the 1950’s, 1996 and 2008 were used to identify disturbance zones, or areas of significant channel change, along 157 km of the main channel for classification according to the four class system of Martin and Pavlowsky (2010). A total of 93 disturbance zones were identified including 59 megabars (63%), 17 extensions (18%), 14 translations (15%) and 3 cutoffs (3%). Forty-four percent of the disturbance zones are located in the 85 km downstream of Lake Springfield Dam, for an average of 0.48 disturbance zones per km, with 56% of the disturbance zones located upstream of Lake Springfield, for an average of 0.71 disturbance zones per km. These channel disturbance patterns are generally spatially-persistent over time and indicate the influence of both the natural controls of shallow bedrock and confined valleys on channel form as well as changes in flood regime and gravel sediment supply linked to human activities.

Influence of Riparian Buffer Width on Disturbance Zone Distribution in Big River, Missouri

Thomas Pesek and Marc Owen
Geography, Geology and Planning
Faculty Advisor: Robert T. Pavlowsky

Bank erosion is a leading cause of property damage, habitat loss, and sediment problems along rivers. Managers often plant trees to restore or maintain bank stability. However, it is common to see severe bank erosion along forested areas in some Ozarks rivers. To examine the role of forested buffer zones on bank erosion rates, this study compares average tree buffer widths along stable channel reaches and unstable, eroding channel reaches to test the hypothesis that the greatest erosion occurs along banks lacking forest cover. The study area is the Big River in the Ozarks Highlands region of Missouri. The methods for this study involve interpretation of aerial photographs using GIS. First, reaches of actively eroding channel were delineated. Second, forest buffer widths were measured at 100 m intervals and an average was found for each bank. Our hypothesis is supported if wide buffer widths tend to surround stable channels and narrow buffer widths surround disturbance zones. Recommendations will report critical buffer widths for bank protection and evaluate the effectiveness of riparian forests in controlling bank erosion.