Forest Service scientists are working with university partners to develop and apply new methods to map mountain peatlands.
Peatlands—also known as bogs, moors, fens, peat swamps, and mires—accumulate organic matter over thousands of years. The layers of peat build up because plant material does not fully decompose in the wet, oxygen-starved conditions. Peatlands cover just 3 percent of Earth’s land surface but store about 30 percent of its soil carbon, about as much as is stored in all land plants. In spite of their environmental importance, peatlands are not well-mapped; in particular, tropical mountain peatlands contain extensive peat soils that have yet to be mapped or included in global carbon estimates.
“This lack of data hinders scientists’ ability to inform policymakers and land managers of management practices to sustain and restore peatlands,” said Erik Lilleskov, a research ecologist with the USDA Forest Service’s Northern Research Station in Houghton, Mich. In addition to storing carbon long-term, peatlands prevent erosion by holding onto water, and filter the water they do release, benefitting human communities downstream. Many peatlands around the world are shrinking or disappearing altogether due to land use changes or other environmental stressors. Some countries are still discovering new peatlands within their borders, so accurately mapping them is essential to their protection and proper management.
Lilleskov and his partners with Michigan Technological University and the Universidad San Francisco de Quito in Ecuador are working in the Andes Mountain Range where rapid large-scale mapping activities are needed urgently to quantify the extent of the country’s wetlands and their current rate of degradation. Although individual mountain peatlands are small in size compared to many lowland peatlands, they are abundant across the Andean landscape and are likely a key component in regional carbon cycling processes.
Remote sensing of these peatlands is challenging because from above peatlands can look very similar to non-wetlands in this cold and rainy region, and steep mountain slopes and cloud cover make it challenging to gather and interpret remote sensing signals. The team’s advanced mapping technique combines data from multiple satellites with information gleaned from core samples of peat to determine the location, size and depth of Ecuador’s peatlands. Drilling repeatedly into the peat with a short, hollow tube with a long handle to extract core samples for analysis allows the scientists to “ground-truth” their satellite information, a necessary process to ensure accurate mapping. This mapping technique accurately estimates both where mountain peatlands are, and how much carbon they harbor.
From the data collected to date, mountain peatlands represent less than 1 percent of the total land area of Ecuador but contain as much carbon as 23 percent of the forest biomass found in that country, which includes extensive tropical rainforests.
When the research project is finished, the Ecuadorian people will have detailed maps of their peatland resources, as well as trained scientists to monitor and protect their country’s peatlands. Ultimately, that information will contribute to an accurate global assessment of peatland distribution and carbon storage, and permit sustainable land use management. The same mapping techniques developed for this project can be applied to peatlands in the Rocky Mountains that have been impacted by roads, ski areas and grazing to quantify their distribution, carbon and water storing capacity, and help protect and restore them.