Research projects


REU student research projects will investigate a range of invasive elements and other stressors affecting the Missouri River including:  
invasive tree and fish species and their effects on birds and food webs, dam-modified sediment loads, competing values and beliefs about the river, 
loss of prairie and wetlands surrounding the river due to land-use change, and agrochemical contamination of the river.


Individual Research Projects


Effects of Invasive Trees on Native Floodplain Forest Vegetation & Breeding Birds

Research mentors: Drs. Mark Dixon and David Swanson, Department of Biology

(2 students/year)

Project Background: Floodplain forests, particularly those dominated by plains cottonwood (Populus deltoides), support among the highest levels of bird diversity of any habitat type in the Great Plains region, but native floodplain forests have been greatly reduced and degraded since the time of Euro-American settlement.  These changes have promoted the invasion of floodplain forests by native upland and non-native tree species.  These changes are likely to substantially impact breeding bird populations and nesting success, so we propose to investigate (1) the factors influencing the abundance and distribution of invasive woody plant species along the Missouri River and (2) the relative habitat quality of habitats dominated by native vs. invasive woody species.  

REU Research Project: For question #1, we will evaluate relationships between landscape factors (e.g., fragmentation), site factors (e.g., soils, management history), historical land cover change and the distribution, abundance, and age structure of invasive woody plants along the Missouri River.  For question #2, we will compare nest site selection and nesting success for bird species occupying habitats dominated by native and invasive trees and shrubs within floodplain forests along the Missouri River. We will compare nesting success using statistical models, with variables including the preponderance of invasive tree species, to determine factors influencing nesting success for floodplain forest birds. REU students will work with Drs. Dixon and Swanson to conduct vegetation surveys, find and monitor bird nests, and conduct statistical analyses of both vegetation and nest data. Students will learn identification skills and survey methods for birds, bird nests and floodplain forest plants, as well as methods of data analyses for bird nesting and community ecology data.

Student Qualifications:  No prior experience is necessary for this research project, but coursework in ecology and ornithology and skills in bird identification would be beneficial.  This project involves field work, so the student must be willing and able to work outside in summer conditions.



Effects of Modified Sediment Loads on Missouri River and Tributary Hydrology

Research mentor: Dr. Mark Sweeney, Department of Earth Science

Project Background: Suspended load is an important component of the total sediment load carried by a river, and it is an important nutrient source for numerous aquatic organisms. The installation of Gavins Point Dam resulted in a drastic reduction in suspended sediment load along the 59-mile stretch of the Missouri National Recreational River (MNRR), while also increasing sedimentation in Lewis and Clark Lake upstream of the dam. A recent two-year assessment of the suspended sediment contribution of tributaries to the Missouri River within the MNRR indicated that the tributaries had minimal impact on the river’s overall sediment load, however, a longer study is needed to evaluate seasonal impacts and long-term trends. A study upstream of the dam sought to determine sources of sediment depositing in Lewis and Clark Lake, predicted to fill in about 160 years. This REU project seeks to accurately determine seasonal changes in suspended load along the Missouri River and its tributaries both upstream and downstream of the dam, and to help identify potential sources of that sediment.

REU Research Project: This research will measure the suspended load concentrations of the major tributaries (from bridges) and the Missouri River (from a boat) at multiple times which will help to determine the role of the tributaries in sedimentation on the Missouri River. The REU student will use a depth-integrated sampler to collect samples and will process samples in the lab. The REU student will compare suspended load data to previous work and analyze the data for trends. S/he will investigate how differing land uses surrounding the Missouri River and its tributaries (e.g. grazing land, row-crop agriculture, riparian forest) affect local sediment contributions and the overall sediment load of the Missouri River. The student selected for this project will work in a geoscience-focused group of 2-3 students and compare data with GIS land-use mapping of the watershed.

Student Qualifications: No prior experience is required for this research project, although introductory coursework in environmental sciences or geosciences would be helpful. The REU student must be able to work outdoors and repeatedly lower and lift a 26-lb sampling device by rope 10s of feet from a bridge or boat.


Effects of Invasive Fish on Missouri River Food Webs

Research mentor: Dr. Jeff Wesner, Department of Biology

Project Background:  Invasive Asian carp are present in the Missouri River below the Gavins Point Dam. While the effects of Asian carp in aquatic food webs are relatively well-studied, their effects on terrestrial food webs are not. The goal of this research is to understand how invasive Asian carp affect linked aquatic-terrestrial food webs in the Missouri River. In particular, Dr. Wesner’s research group measures how invasive carp affect emerging aquatic insects and the terrestrial predators they feed. They use manipulative experiments and field surveys to determine whether carp ingest insects during feeding, and if their presence alters the emergence of aquatic insects to terrestrial ecosystems. The effect of carp on emerging aquatic insects will be measured directly by isolating Asian carp in enclosures in the Missouri River and in artificial streams at USD’s Experimental Aquatic Research Site (ExARS). The carp’s effect on terrestrial food webs will be measured by quantifying the density of terrestrial long-jawed spiders, which track aquatic insect emergence.

REU Research Project:  The REU student will assist with manipulative experiments, and will lead the diet survey with the assistance of Dr. Wesner. Specifically, the REU student will collect fish, extract gut contents, and identify prey items to determine whether Asian carp ingest insects (directly or indirectly). The REU student will learn concepts in life-history, entomology, food webs, experimental design and ecosystem ecology.

Student Qualifications:  Required qualifications are an ability to work independently and in relatively strenuous outdoor conditions. Preferred qualifications include coursework in ecology, ichthyology, experimental design, or other related subjects.


Construction of a Missouri River Participatory Geographic Information System Database

Research mentors: Drs. Matthew Sayre and Silvana Rosenfeld, Department of Anthropology

Project Background:  Participatory Geographic Information System (PGIS) enables the integration of historical and ethnographic data with spatial data. A PGIS database provides a means to organize historical and ethnographic data collected across the landscape and run valuable spatial analyses. Whereas traditional GIS modeling can be used to combine cultural and natural datasets into a simple cohesive format that allows for the examination of patterns in data features and to run spatial analyses, a PGIS goes further by including local voices in the entire database construction process. The resulting data will allow users to examine land use, pollution sources, and cultural ideas and practices. This research constructs a PGIS database that works with archival findings and communities of traditionally associated peoples to map and document historical relationships, changing relationships with invasive inputs, and contemporary values and beliefs associated with the Missouri River.  



REU Research Project (2017):  The REU student will construct a PGIS database; GIS expertise is required.  This will require the student to do survey work and data processing and evaluation. This project will need to establish a baseline map of early land-use in the area. The REU student will work with archival findings and communities to map and document historical relationships with the land. This will include mapping early cultivation practices and how they shifted over time.


Terrestrial Land-Use Changes along the Missouri National Recreational River

Research mentor: Dr. Brennan Jordan, Department of Earth Science

Project Background: Wetlands, vegetated natural swales, and perennial stream channels provide critical ecosystem services by slowing surface-water runoff, increasing infiltration, and thus increasing natural filtration and improving water quality. Increases in agricultural commodity prices have motivated significant land-cover/land-use change (LCLUC) from of wetlands, grassland, shrubland, and forest to agriculture in South Dakota and adjacent states. Regional studies of LCLUC commonly use USGS LANDSAT imagery with a 30-m resolution, sometimes using time-series images from GoogleEarth for validation. Such studies miss fine-scale (<30 m) LCLUC within fields. These fine-scale changes, particularly in vegetated natural swales and perennial stream channels, may be cumulatively significant.

REU Research Project: An REU student will conduct a survey of fine-scale land-cover/land-use change in selected sub-watersheds of watersheds that drain into the Missouri River. Historical imagery in GoogleEarth will be used as the primary observations, and observed changes will be compiled in ArcGIS for analysis, with field validation of selected sites. The student will calculate the linear fraction of LCLUC in swales/perennial steam channels in studied areas and consider possible impacts on water quality.  The student selected for this project will work in a geoscience-focused group of 2-3 students with additional GIS and field components.

Student Qualifications:  A working knowledge of ESRI’s ArcGIS software is necessary for this project.  Students should only apply of this position if they will have completed at least one course in GIS or geospatial information technology by the time the summer program begins.


Understanding Competing Value Claims of the Missouri River

Research mentors: Drs. Matthew Sayre and Silvana Rosenfeld, Department of Anthropology

Project Background:  How people understand and assign value to natural systems affects their interactions with those systems. In an analysis in the Missouri River basin, Gewertz and Errington (2015) have described this key issue as: “Discussions of nature’s worth in South Dakota (and elsewhere) frequently take the form of competing value claims concerning private gain versus public trust, nature as having instrumental versus inherent significance, and the control of private property versus state and federal systems of authority.” Focusing on competing value claims lays out some of the differences between what people consider economically valuable as opposed to what they state to be their broader values. 



REU Research Project (2017):  This social-science research evaluates land-use practices in the Missouri River and its uplands in order to document how changing use patterns and species’ composition impact communities’ views of the river. This will include ethnographic surveys of local perspectives on farming, ranching, recreation, and other activities conducted alongside the river. This research informs the Participatory GIS research described above, and the students from both projects will work collaboratively.  Surveys and interviews will be used to elicit ideal visions for a sustainable UMRB with a specific focus on land uses and human health and wellbeing. This work will be combined with archival research of early perspectives on land-use. During summer 2017, the REU student will collect archival materials about changing land-use over time. 


Interactive Effects of Contaminants & Pathogens on Amphibians along the Missouri River

Research mentor: Dr. Jacob Kerby, Department of Biology

Project Background:  Corn and soybean production, which routinely includes the use of multiple agrochemicals, is the dominant land use in the MNRR watershed and is the leading cause of water pollution within the Corn Belt. Additionally, new strains of deadly pathogens are continually being introduced into altered aquatic systems like the Missouri River Basin. The interactive effects of agrochemical pollution and increased pathogen load has been purposed to be a potential cause of amphibian declines across the US, and is likely contributing to the declines of amphibian abundance in the Missouri River Basin. Due to the large number of potentially problematic contaminants in the Missouri River system, Dr. Kerby’s research group conducts both field and laboratory studies examining the impacts of agrochemicals and disease dynamics in several amphibian species. Dr. Kerby’s group has extensively researched the potential interactions between contaminants and pathogens along the Missouri River using amphibians as the focal taxon. His research group runs thousands of samples annually to diagnose the presence of amphibian pathogens via quantitative PCR methods.

REU Research Project:  The REU student will gather water quality data on contaminant concentrations via field surveys along established Missouri River study sites. The student will also examine the interactive effects on amphibian disease via experimental manipulations. This work will provide important information on water quality and its potential effects on aquatic organisms. Additionally, it will provide a wide range of training opportunities for the REU student including field-survey methods, toxicological experiments, and molecular laboratory skills.


Ethnohistorical Relationships among American Indian Tribes & the Missouri River

Research mentor: Dr. David Posthumus, Department of Anthropology

Project Background: In order to understand the Missouri River basin as a dynamic ecosystem, and in particular, the impacts of invasive elements on the sustainability of the river and those who depend upon it, an ethnohistorical baseline explicating the relationships between the Indigenous inhabitants of the region, the Missouri River, and its resources must be established. Numerous American Indian tribes are connected to the Missouri River basin, including the Sioux (Lakota, Yankton, and Yanktonai), Omaha, Arikara, Mandan, and Hidatsa, yet an ethnographic synthesis of these relationships has not been completed.

REU Research Project (2017): The objective of the first phase of this research is to establish a baseline of cultural and historical data documenting traditional Indigenous relationships with the Missouri River in the Plains region. Utilizing ethnohistorical sources—both published and unpublished archival materials—this research explores and documents the historical values of Native communities who have lived in close proximity to the Missouri River and their evolving patterns of interaction with it. In particular, this research seeks to identify traditional cultural properties: “significant remnants of the past, present, and future of Native American and other traditional societies” (Kenmotsu et al. 1995:237) or places “associated with cultural practices or beliefs of a living community that (a) are rooted in that community’s history, and (b) are important in maintaining the continuing cultural identity of the community” (Parker and King 1990:1). Dr. Posthumus’s research expertise and the resources contained in USD’s South Dakota Oral History Center, which remain largely untapped by scholars, are strong assets to the project.

Student Qualifications: No prior experience is necessary for this research project, but coursework in anthropology, history, and Native American studies are preferred. The REU student will combine methods and theory from both anthropology and history. The REU student will address pre- and early-contact period ecological relational patterns of Indigenous peoples in the region with the Missouri, focusing on subsistence and sustainability. Using data from both primary and secondary sources the student will construct a baseline of ethnohistorical data that will be used in the next two phases of this project.


Reincorporating Prairies into Missouri River Landscapes

Research mentor: Dr. Meghann Jarchow, Sustainability Program and Department of Biology

Project Background: Tallgrass prairies, which are the native ecosystem of most of the MNRR watershed, are among the most endangered ecosystems globally with less than 5% remaining. Prairies are known to enhance environmental quality compared to agricultural uses and can also provide a number of marketable goods. Whether prairies are used to produce marketable goods or maintained for biodiversity conservation, they are actively managed, and that management affects the composition and functioning of the prairies. Dr. Jarchow’s overall research focus examines how management activities affect diversity and plant community composition in tallgrass prairie.

REU Research Project: The objective of the experiment included in the Sustainable RIVER project is to determine how two factors, the timing of disturbance and plant functional-group identity, interact to affect biomass production, plant community composition, and exotic species invasion in managed tallgrass prairie systems. This research is based on a 0.8 ha field experiment near Vermillion, SD that was initiated in 2014 (for more information about the experiment see Dr. Jarchow’s website). In the experiment, Dr. Jarchow’s research group measures plant community composition, aboveground biomass production, and root biomass. The REU student will work with Dr. Jarchow’s group to assist with all aspects of the experiment. Additionally, the REU student will choose a research topic for her/his project beyond the research currently being conducted on the experiment (e.g. effects of the treatments on floral resource availability, effects of the treatments on mycorrhizae colonization of roots). Through this project the REU student will learn common plant community ecology research and data analysis methodologies (e.g. plant diversity sampling, statistical analyses). The REU student will also learn prairie-plant identification.

Student Qualifications: No prior experience is necessary for this research project, but coursework in ecology is desirable. This project involves field work, so the student must be willing and able to work outside in summer conditions.