Soil is critical to human civilization. Without it, we would not have natural ecosystems, agriculture, accessible aquifers, and many other benefits that make earth habitable. To be healthy, soil relies on millions of microbes to carry out processes that ensure the right nutrients are available. One of these processes is called denitrification, in which nitrogen dioxide (NO2) is turned into molecular nitrogen (N).
“The denitrification process is extremely important to microbial and overall soil health, yet the scientific community really doesn’t know enough about it,” says Alburuj Rahman ’16. “There remain a lot of soil secrets.” A biology major, Rahman works with Professor James P. Shapleigh, Microbiology, to unearth some of these secrets.
He first became interested in science through his mother, an astrophysicist, who encouraged him while growing up to “delve into the unknown.” Coming to Cornell, he was especially interested in the relationship between math and science.
“We work with a lot of different groups, which is allowing us to create a pretty large database for use by researchers around the country,” says Rahman.
Math and Soil Science
When he came across the Shapleigh lab, he knew it would be a good fit for him. “The lab looks at how we can use statistics and other types math to understand the ways biology and natural earth systems function,” he explains. Rahman uses both math and natural sciences in his research now. His project focuses on the microbes responsible for the denitrification process in soil. Using soil samples from the Hubbard Brook Experimental Forest in the White Mountains of New Hampshire, he writes programs to categorize the strains of DNA present in order to identify microbes.
In addition to the programs that identify microbes, Rahman has helped create programs that identify the proteins they secrete. “This tells us what stage of denitrification they’re in, which allows us to track the progress of these processes,” Rahman says. The team then classifies the data in two ways: functionally and taxonomically. Functional classification helps to discern which proteins are present, while taxonomic classification determines which microbes are producing the proteins. “It’s really difficult to identify microbes amongst seemingly innumerable possibilities, which is why our work is important,” Rahman emphasizes.
The project is truly collaborative. “We work with a lot of different groups, which is allowing us to create a pretty large database for use by researchers around the country,” says Rahman. The Shapleigh lab relies heavily on collaboration with other research institutions, such as Columbia University.
Supporting Life on a Changing Planet
“All applications for our research are still unclear,” Rahman says. “But with a planet that’s changing so rapidly, we have to understand the processes responsible for life if we want to continue to support life on it.” He lists climate change and deforestation as two phenomena that are changing our soils, and not for the better. “The Obama administration has been talking a lot about the need to move forward on policy for a changing planet. The best course of action should be based on research done by groups like ours,” Rahman states.