Bacterial Community Adaption to Nutrient Regime Changes in a Midwestern Reservoir by the Saxton Aquatic Micrbiology Lab

Research Team

Natalie Heim, Taryn Willrath, Glorimar E. Sellas Ramírez, Carly Prochazka, Amy Weber, Michael Vanni, Matthew Saxton 

Department of Biology, Miami University, Oxford, Ohio 45056

Abstract/Introduction

Currently, there is a major issue in reservoirs and lakes everywhere with the frequency of algal blooms. Although our main study is determining how bacteria communities adapt to seasonal changes in the nitrogen-to-phosphorus ratio we are currently focused on how these nutrient shifts influence community composition across seasons. We hope that this will in turn help tackle our long-term goal of reducing the severity and frequency of algal blooms and improve water quality. We started by analyzing water samples from Acton Lake that were collected over the span of a year. After processing this data in RStudio we then further analyzed a subset of the data between July and August and created our different graphs. In our Alpha Diversity graph the Shanon diversity range is 5.0-5.6 and the Simpson diversity range is 0.981-0.993. For our Abundance graph Cyanobiaceae appears strongly in July and August and Nostocaceae is only prominent in late July. Our Bray NMDS graph showed that our group from August 12th was more tightly clustered together and the July 29th group was loosely clustered together. 

Conclusions and Future Study

Conclusions:

In our Alpha Diversity graph, we were able to see that our data has a relatively high diversity throughout the season, noting that no single bacterium was significantly more prevalent than the others. Our Abundance graph further supported this. Each colored segment of the graph stood for a different bacterial family, showing that different bacterial families rising and falling across the season. Together with the alpha diversity results, this tells us that while the overall diversity of the community stayed stable, the specific members of that community were shifting across the season. As for the NMDS graph we were able to see the same trends. Each date forms its own cluster and the community composition is genuinely different across sampling dates, not just randomly scatter which supports the abundance graph witht the falling and rising of families. Overall, these results heavily support the diversity in the ecosystem through the season, and this is important because more diverse communities tend to be more functionally stable, they have more redundancy, so if one group of bacteria is lost, others can fill that role. It's a sign of ecosystem health.

Future study:

• Determine how nutrient shifts influence community composition across seasons

• Reduce the severity and frequency of algal blooms and improve water quality

Acknowledgements

• Dr. Kiss CBFG

• NSF

Citations

Miami University. "You Live in a Watershed!: 

Student-Designed Exhibit Aims to Educate State Park Visitors." 17 Dec. 2014, https://miamioh.edu/news/top-stories/2014/12/watershed-exhibit.html

NACE Career readiness Competencies

Through our research process we demonstrated many NACE Competencies including teamwork, technology, and professionalism. We cooperated as a team, communicating with one another to create results and our poster. Entering our lab we learned how to use and navigate RStudio in order to analyze our raw data. Furthermore we demonstrated our dedication to the study by asking questions and being on time to meetings.