A group of MIT students presented their findings Thursday from a field study earlier this month in Puna that looked at Kilauea’s residual volcanic emissions and the health of surrounding ohia forest.
The students were part of Massachusetts Institute of Technology’s Traveling Research Environmental eXperiences (TREX) program, which affords undergraduate environmental and engineering majors from the East Coast institute hands-on studies and experiments on their winter break.
The 14 undergrads — as well as three teaching assistants and two professors — set up a home base in Mountain View, where they spent two weeks observing and analyzing residual volcanic emissions at Kilauea’s Fissure 8 and the ohia forest around it.
In their presentation, the students explained when Kilauea was erupting, sulfur dioxide, carbon dioxide and water particles were released into the atmosphere.
After eruption activities ceased in September 2018, the group wanted to measure residual emissions by setting up a sensor approximately 100 meters from the fissure. They recorded sulfur dioxide levels over a period from Jan. 16-22 by measuring emissions related to humidity, temperature and wind direction.
Their data showed SO2 levels peaked around 9 a.m. with maximum levels occurring on Jan. 18 at 113.4 ppb. The EPA sets the maximum safe level at 75 ppb, with higher levels affecting sensitive groups. Their conclusion from data gathered inferred levels of SO2 rose under conditions of lower humidity, which is why residents in the lower Puna area could smell sulfur when rain subsided that week.
The next group presented their findings on ohia forest health in the Waiakea Forest Reserve.
They discussed the importance, both culturally and ecologically, of the tree, noting ohia is one of the first trees to inhabit lava flows, which leads to soil creation.
To study the impacts of rapid ohia death (ROD) and the invasive strawberry guava on the forest, the students gather data over a 5,000 square meter area. In the area where strawberry guava was prevalent, ohia only accounted for 11% of the canopy. This, they said, shows how the invasive species is able to take over a healthy forest.
The group proposed preventative measures for controlling the nonnative species that included fencing, hand-cutting, herbicides and controversial biocontrol.
They also concluded that when ohia dies from ROD, it makes room for strawberry guava, which further degrades the forest.
The students also studied volatile organic compounds (voc) emitted from ohia using a gas chromatograph mass spectrometer. They were looking for resveratrol, which is released when a plant is under stress and being attacked by pathogens, such as the ROD fungus. Although their study was too short in duration to draw conclusions from that study, the students believe voc will be different in healthy ohia versus ROD infected ones.
Future research using longer sample time and longer research duration will need to be done in order to compile significant data, the said.