“My research broadly looks at root functional traits of grasses and how roots are adapting to changes in nutrient availability," said Abby Schmidt, a master’s student at USU who works in Kruger National Park. Her research centers on roots, enzymes, nutrients, and fire.
“Savannahs are fire prone ecosystems and have been for millions of years," Schmidt said. "That's one of the key drivers in maintaining savannah vegetation structure, with a kind of mix between grasses and trees where they're coexisting."
Though Schmidt does most of her analysis in the lab, she does need to get into the field to collect her samples.
“So, I am collecting plants from the annually burned treatments, and then the tri-annually burned treatment and the unburned, which is the control, treatment,” she said.
By collecting grasses from these three areas, Schmidt can compare physical root traits associated with nutrient uptake along with chemical and metabolic traits to see if grass roots in areas with alternate fire regimes are actually significantly different.
“The idea here is that in savannahs — where fire is more frequent — there is more available phosphorus for these plants to take up," Schmidt said. "But in areas where fire becomes less frequent, you would see less available phosphorus for plants."
Schmidt looks not only at the physical complexity of the roots, but also at the enzymes they produce.
For example, in areas with less fire — and thus less available phosphorus — the plants should be producing more enzymes that convert unavailable phosphorus into a form that they can use.
“So, I'm able to directly look at how these different fire frequencies are affecting the soil chemistry, and then how that soil chemistry is affecting plant function,” she said.
In the era of climate change where fires are predicted to be more frequent and natural resource management is key, Schmidt thinks her research could shed light on soil and plant nutrient dynamics. But she doesn’t plan to stop at Kruger.
“What I would really like to do is look at this across other savannah systems, not just Kruger, but also in the Sertão or other systems, maybe in North America or across Africa, to see if this is something that's happening everywhere,” said Schmidt.
While it’s possible the trend will hold, we just don’t know yet. Which is really why we do science in the first place.
