A paleolimnological record of anthropogenic disturbances at Holmes Lake, Adirondack Mountains, New York

Holmes Lake, Adirondack Mountains, New York, is a clear-water acidic lake that was treated with lime in 1983 to permit stocking of trout. Diatom assemblages in dated sediments reflect three anthropogenic modifications of the lake ecosystem: 1) assemblages from the mid- and late 1800's are associated with historical and sedimentary records of forest clearance, and indicate slightly increased pH; 2) acidobiontic species increase in sediments from the mid-1900's, a period of local reforestation and regionally increasing anthropogenic acid loading; 3) liming caused large increases of circumneutral periphytic species in the first growing season, and decreases of acidobiontic species by the second.