PhD candidates Cecilia Howard and Diana Velazquez are collecting underwater sinkhole samples for analysis in the Thunder Bay National Marine Sanctuary in Alpena. They conducted similar research last year and returned to Thunder Bay recently for more sample collection.
Cecilia and Diana used sediment traps to gather particulate matter for long-term studies on the impact of low-oxygen conditions in the Middle Island Sinkhole, especially focusing on nutrient cycling of essential elements like carbon and nitrogen.
“It was deployed over winter,” said Cecilia. “We redeployed it in October, and now we are cleaning it up. This is a sediment trap, which collects particulate matter that’s falling down in the water column and funnels it down into a bunch of bottles, and, on a schedule, we’ll rotate the bottles, so you can get samples that were collected over this time period.”
Those samples will then be analyzed to determine any changes or discoveries about the sediment.
“We’re really interested in how the low-oxygen conditions in Middle Island Sinkhole impact nutrient cycling of essential elements like carbon and nitrogen,” said Diana. “So we’re basically tracing, what are the sources that make their way into the sediments and are ultimately preserved in Middle Island Sinkhole.”
Read more about Cecilia’s and Diana’s research here.
