This year, Plymouth State University’s (PSU) Center for the Environment and the White Mountain National Forest (WMNF) have worked together on assessing the condition of water bodies within the national forest in New Hampshire and eastern Maine.
“The Forest Service has a responsibility to ensure that state water quality standards are met while at the same time allowing the WMNF to support a variety of uses such as recreation, forestry, and wildlife habitat,” said Sheela Johnson, WMNF hydrologist. “One way we do this is to collect water samples from streams, ponds, and wetlands throughout the forest and analyze the samples monitor the water quality.”
The WMNF asked the Center for the Environment to assist in collecting water samples and other field data, and managing those data for future use. Mark Green, the Center’s hydrologist, worked with James Sherrard on the project giving him valuable applied work experience in hydrology and land management.
“Many of the sites I sampled were near WMNF recreation sites such as campgrounds and also areas near recent timber harvests. Sampling these locations allows the Forest Service to make sure their land management activities do not impact water quality,” said Sherrard. “Some data we can collect on site and other data are generated after the samples are tested in a laboratory. All of it is entered into a WMNF database so it will provide information that will be useful in the future.”
Land management activities such as timber harvests on the WMNF are designed to protect water bodies using Best Management Practices (BMPs) such as buffers of undisturbed forest around the water. Monitoring the streams, ponds, and wetlands assures that the design, location, and implementation of these BMPs is adequate for protecting water quality.
A unique part of the project was testing a new protocol for sampling groundwater dependent ecosystems, or areas where ground water emerges to the surface such as seeps, springs, and wetlands that are often rich in terms of their soils and plant life. The WMNF was one of five sites selected by the US Forest Service to assess a new integrated process that combines data on soils, vegetation, and water at these sites to help give a more complete assessment of the health of these areas. Johnson explained that, “The WMNF is interested in understanding the ecological value of groundwater dependent ecosystems and knowing if land use in the watershed is affecting these values. Monitoring these areas is also important as climate change may alter the groundwater sources in these areas.”
The work has provided an additional environmental research opportunity for PSU. The Environmental Research Laboratory now has the capability of measuring stable isotopes of hydrogen and oxygen in water, which can be used to trace water sources. For example, groundwater usually has a distinct signature, allowing its relative abundance in lakes, streams, and other surface water to be detected. Analyzing the isotopes of water samples from springs, seeps, and wetlands that are believed to be dependent on groundwater will verify if groundwater is the primary source.
Green explained the application of water isotopes to the WMNF project, “We can measure the isotopic composition of water at these groundwater dependent ecosystems to gain more insight into their hydrology. Furthermore, as we make more regional measurements, we can understand how much groundwater at the surface it takes for these unique ecosystems to thrive, or understand which ones may be near a threshold where any decrease in groundwater flows might endanger the ecosystem.”
Sherrard’s work involved sampling water at groundwater dependent ecosystem sites at different elevations across the WMNF, including Mt. Washington, and measuring their stable isotopes to see if the isotopic composition changes at different altitudes. This information will be useful to both the Center for the Environment’s continuing research on regional hydrology and the WMNF’s ecosystem management.
“Understanding the region’s hydrology while concurrently monitoring water quality helps both our research and the Forest Service’s land management,” noted Green. “It has been great seeing if these isotope measurements can help the management on the National Forest.”
Johnson agreed, “Working with PSU’s Center for the Environment has given us new tools to consider in our work and helps inform our land management decisions. We look forward to developing similar projects in the future.”