THE RESINOUS SCENT of Engelmann spruce wafted over a shallow, mossy pool surrounded by lush sedges near the 11,800-foot summit of Ophir Pass, in southwestern Colorado’s rugged San Juan Mountains. This type of wetland, known as a fen, forms when perennial water saturates the ground, limiting plant decomposition and allowing organic matter to accumulate as peat.
Just downhill, however, on that hot, sunny July day, another part of the fen was visible: a degraded area, bare soil exposed on a steep slope.
Peatlands — fens and bogs — are key climate regulators. (Bogs are maintained by precipitation, but fens, which, in North America, occur in the Northeast, Midwest and Mountain West, depend on groundwater.) Their peat retains plant carbon that would otherwise decompose and be released as carbon dioxide. Despite…