Anyone who has walked the path between the Post Learning Commons and the Science Center at Saint Joseph’s has likely noticed signs that indicate the latter’s “green roof.” But what really goes on up there? Martin Ryan ’19 and Connor Long ’19 are exploring the answers as part of a project for the Summer Scholars Program. Together, they are analyzing the microbes in the soil of the green roof in search of bacteria and to discover the types of carbon sources they use.
“We both wanted to know more about the bacteria that live in the soil,” says Long, a biology major from Aston, Pennsylvania. “The green roof is a great resource to have on campus for this type of research.”
Long and Ryan collect soil from different areas on the green roof using a soil core sampler and then place the soil into a 50ml tube and fill it with water. After creating a dilution, they place the liquid onto an agar plate — a Petri dish that contains a growth medium — to count the colonies of bacteria within the soil. Finally, they use a pipette to place the solution into a Biolog “EcoPlates.” This tool has 96 wells, with three replicas of 31 different carbon sources and three wells filled with water that serve as the control. Long and Ryan use this to detect carbon: if the carbon solution turns purple upon contact with the soil solution, the bacteria in the solution is using that specific carbon source.
Their mentor for this research is Karen Snetselaar, Ph.D., graduate director and professor of biology, who has research experience in urban ecology. She has previously mentored students through the Summer Scholars Program on the green roof, and says that Long and Martin’s research has practical value for those who want to start green roofs in the Mid-Atlantic states.
“Because green roofs are still new in the United States, there isn’t a lot of information on some aspects of their ecology,” Snetselaar explains. “When our roof was started in 2010, the soil was essentially sterile, so it’s an opportunity to examine the kinds of microbes that colonize in the soil early on.”
By examining the four types of soil plots on the roof, the two scholars’ ultimate goals are to discover a difference between carbon sources, draining systems and whether there are dry or wet spots.
“So far,” says Ryan, a biology major form Webster, New York, “we have noticed that carbohydrates are the primary carbon source being used.”
Both students sought places in the Summer Scholars Program to engage in independent research and to discern their career paths, which include either research or medical school.
“Summer Scholars allowed me to pursue a question in science independently,” says Long. “I’ve become more involved and confident in my research as the weeks have progressed.”
To Ryan, Summer Scholars provided a chance to set himself apart from the rest of his classmates and to answer his own scientific questions.
Snetselaar enjoys working with both of the students, who each took a course in environmental microbiology, initially sparking their interest.
“Connor and Martin have a lot of data that they are working with to present in an understandable way,” says Snetselaar. “They are doing a great job of learning to read the literature in the field and then adapting methods used by other researchers to their project.”
Outside the research lab, Ryan is on the SJU Gaelic Football Club team and plays in intramural sports. He is also a member of Sigma Zeta Honors Society and Alpha Epsilon Delta Honors Society. Long also plays intramural sports and is involved in Sigma Zeta. Both students are on the Dean’s List.
Project Title: Microbial analysis using Biolog EcoPlates™ to Study Microbes Contained in the Soil of Different Plants Growing on the Green Roof
Mentor: Karen Snetselaar, Ph.D., professor of biology
Hometown: Aston, Pennsylvania / Webster, New York