Initial Publication Date: June 30, 2022

Using Project EDDIE modules in Environmental Science Senior Seminar

Gaston "Chip" Small, University of St. Thomas (MN)

About this Course

Environmental Science Senior Seminar

Lecture and Lab

Upper Level Undergraduate

students in the course

EDDIE Module Developed

This module explores seasonal dynamics in hydrology and biogeochemistry in a freshwater estuary. Students use a dynamic mixing model to tease apart the contribution of different sources of water at different locations throughout the estuary, and then use these results to infer hotspots of nutrient dynamics.

Jump to: Course Context | Teaching Details | Student Outcomes

Relationship of EDDIE Module(s) to my Course

This module would be appropriate an upper-level undergraduate aquatic biology, hydrology, or biogeochemistry course. My environmental science capstone course had a heavy aquatic biogeochemistry focus this semester, with students conducting research on urban lakes, so this module was an opportunity for them to dive into some real-world data before launching into their own projects.

Teaching Details

What key suggestions would you give to a colleague before they used the activity in their teaching?
In terms of context--students should have some background in eutrophication, and understanding why we care about nutrients in aquatic ecosystems. This module is also good for thinking about the assumptions behind models (both implicit and explicit) that scientists use all the time. The purpose of this activity is to show that, when you combine information with some basic assumptions and laws of mass balance, you can squeeze out new information. Sometimes science involves going out and directly measuring something, but sometimes it requires making inferences.



How did you address challenges in teaching with the module?

For our class, lab periods are dedicated to students working on their own research projects, so I had to use three one-hour "lecture" periods. It would work better to have a longer block of time.

There are some options described in the instructor handout for adjusting the length of time this activity takes. I had all of my students do all of the analyses and we were short of time.


Student Outcomes

Most of my students were not familiar with mixing models before this activity (although a couple of students had used them in their research with stable isotopes), but they are certainly familiar with weighted averages in calculating course grades, so they did have some relevant background knowledge. This activity is an application of applying a quantitative model to make inferences about dynamics in a complex environmental system. I also introduced students to principal component analyses through this activity. Again, that's something that could be included or taken out at the instructor's discretion.

The mixing models are over-defined, meaning that there is not a single solution that fits all of the data perfectly. This is because of both measurement error and (more likely) violations of the assumptions of the model. By manually finding the best solution to the mixing model, students get a feel for the sensitivity of the model to various parameter values, and the benefits and limitations of this model.