RUMNEY — Quincy Bog Natural Area may be best known as a local spot that provides opportunities for recreational walking, observing plants and animals and attending organized programs and walks for residents and visitors in the Pemi-Baker area.
But its educational mission extends further with partners. Local teachers run field trips with younger students hoping to earn a Jr. Naturalist Badge. University researchers bring students to apply their academic learning and research techniques to questions in a real-world setting.
Dr. Lisa Doner is one such researcher using the Bog as a teaching tool. Doner is a member of the Center for the Environment and the Department of Environmental Science and Policy at Plymouth State University.
Recently she led a group of future scientists to conduct field research and collect samples from underneath the ice at Quincy Bog, in the middle of winter. During the following semester, students began a basic analysis on the collected material at the sedimentology lab on the Plymouth State University campus.
What secrets are hidden in the layers of mud, sand and clay beneath the Quincy Bog in Rumney? First a couple of definitions to ground the reader. The students used methods from two branches of science called paleoecology and paleolimnology.
Paleoecology is the branch of ecology that deals with the interaction between ancient organisms and their environment. Paleolimnology is the study of ancient lakes from their sediments and fossils.
The primary method used in this study is analyses of physical characteristics of the sediments underlying the pond at the Quincy Bog. This includes each sample’s density, ratio of mineral to organic material, particle-size and tendency to respond to weak magnetic fields.
Two kinds of cores were collected: a surface core, that captures the delicate interface between the water and the sediments, and a long core. “The surface core is important,” said Doner, “because it holds recent sediments. It forms the bridge, in essence, between our written record and the geologic record, since they overlap in time.”
She continued to explain that the surface might contain a “record” of recent beaver dam expansion, Quincy Bog Road construction and development projects, and floods that occurred in the last century. The long core, according to Doner, is a sequence of 1-meterlong cores.
“The long core provided several surprises,” she said.
First, it seems that the pond at the Bog has been around for a very long time and that beaver are not the sole reason for the area being a wetland.
Second, the long core contains materials near the bottom that are consistent with glaciers that passed through New Hampshire 12,000 years ago. Therefore Doner surmises the core must contain at least 12,000 years of “geologic memory.
The last surprise comes from preliminary analysis of the surface core. “In recent times, perhaps within the last 150 years,” said Doner, “an enormous disturbance, or multiple disturbances, changed the character of the site.”
Before she can tell more about these disturbances, Doner needs to learn the age of the sediments involved. With the help of a grant from the Geological Society of America, two undergraduate environmental science students will use lead dating techniques which provide a timeline for events of the past 150 years.
“Having information about the age of the sediments will allow us to look at the deposits laid down during 1927, 1936, 1938, 1973 and 1989, to determine if the historically large floods in these years left a mark in the Bog’s sediments,” said Donor.
Other possible explanations will be reviewed as well as the cores continue to be studied. Additional dating is underway, using radiocarbon analyses to provide ages covering thousands of years.
To read more about this interesting project check out the current volume of Bog Notes at http://www.quincybog.org/bognotes.htm. Quincy Bog volunteer Dan Kemp has prepared a documentary of this activity and it can be viewed on the Quincy Bog website at http://www.quincybog.org/bognotes.htm.