It’s late May in Northern Michigan. Baby oak and maple leaves are growing toward light that on this day shines down in abundance. Four mini-vans caravan into the forest and stop at the UMBS Burn Plots, those ¼-acre sections of forest that have been progressively cleared and burned in 20-40 year increments. Students pile out of vans, bringing buckets of measuring tapes. Immediately the mosquitoes begin an assault. This is week one of the Introductory Biology Lab at UMBS. For the next month, these 20 students will study carbon cycling and forest disturbance first-hand. Along the way they’ll learn the concepts, such as experimental design, figure preparation, and data analysis, and skills, like using a research-grade balances, performing serial dilutions, and pipetting, that are the ends of a traditional introductory lab course. Seven months later, one of the labs from this course is the featured “Resource of the Week” on the website for QUBES, a national network of biology instructors.
The Biological Station began hosting basic college Biology and Chemistry lab classes in 2017. The courses are funded by a Transforming Learning for a Third Century grant from the U-M Provost’s office and the Authentic Research Connection (ARC) program at U-M. ARC classes organize introductory student experiences around ongoing faculty research rather than “cookbook” experiments that don’t relate to any larger inquiry.
Students in the UMBS biology lab are learning the foundational ideas behind work that a team of researchers have been pursuing for over a decade. Gil Bohrer (Ohio State), Peter Curtis (Ohio State), Chris Gough (VCU) and Chris Vogel (UMBS) intentionally “disturbed” a nearly-100-acre section of UMBS forest by killing all of its aspen and birch trees in the “Forest Accelerated Succession ExperimentT” (FASET). They then studied the changes in net carbon sequestration (a.k.a. flux) as the dead trees decomposed (releasing carbon) and new trees filled in (capturing carbon through photosynthesis).
A Lesson Worth Sharing
In one assignment for the class, students explore how net carbon measurements are affected by environmental variables such as soil moisture, temperature, and time since disturbance. They use flux data from the UMBS AmeriFlux monitoring tower (and other towers throughout the FLUXNET network) to test their predictions of how environmental conditions would affect carbon flux.
“It was very helpful in introducing us to the concept of carbon cycling in forests,” says Annie Bonds, a student from Introductory Biology Lab. “Many of us had never really learned about this prior to taking the class.” Another student, Summer Eubank, says “One thing that surprised me was how a relatively small disturbance, like a falling tree, could greatly affect the carbon cycle. And you could tell based off of the data from the AmeriFlux tower.”
It is this lab, complete with links to data sources, explanatory slide shows, and recommended discussion questions, that appears this week as the QUBES Featured Resource. QUBES is a network of scientists and science educators who share STEM instructional materials. One of the services it offers is a free repository of classroom resources that are tagged by DOI (digital object identifier). Says Introductory Biology Lab instructor Cynthia Giffen, “A very cool thing about these instructional modules is that they are designed to be complete packages to give an instructor everything they need to teach the module in their course. It's a great way for instructors to expand their course to include high quality materials developed by an expert in that field.” In addition contributing this to the QUBES platform, the team will present a poster on the lab resource at the American Geophysical Union (AGU) Fall 2018 meeting in Washington, D.C. on December 14, 2018.
More Questions to Answer
Introductory Biology Lab ARC will return to the Station this May. Students will explore more of the unfolding story of carbon sequestration in forests disturbed by pathogens and in which the natural process of succession has been altered. The Gough lab received funding for a follow-up study to FASET. They will again cause forest disturbance by killing trees. But this time they will aim for 3 different levels of disturbance -- low, medium and high -- across all trees in the plots, not just aspens and birches.
Giffen’s students will be watching, talking with and learning from the research team, using the lab featured on QUBES as well as others that Giffen and Gough developed expressly for the class. “One interesting result [from the 2018 class’s research] was that the carbon-nitrogen ratio in spring leaves was much lower than what the historical FASET dataset showed,” Says Giffen. “We don't know why that is, so that's a result we'll see if we can repeat and investigate more.”
Bonds says exploring these real-world questions was her favorite part of the class. “As someone intending to go to grad school and conduct similar ecological or geochemical research someday, this course was a wonderful opportunity to learn how it is done, in a hands-on way, from other researchers in the field.”