The ecology of sedges (Cyperaceae) in Maine peatlands

Sedges (Cyperaceae) are the most important family of vascular plants in terms of species richness on Maine peatlands. Carer has more species than any other genus including Sphagnum in these peatlands. Optima (abundance weighted means) and tolerances (abundance weighted standard deviations) of pH, Ca, and shade are given for the 21 most frequently occurring sedge species. These species are also characterized in terms of habitat (vegetation type). Most of the species occur in the open, but a few (e.g., Carer trisperma) are most abundant in wooded habitats. Eriophorum species characterize bog and poor fen habitats. The rarest peatland sedges are all calciphiles. Canonical correspondence analysis with forward selection entered shade, pH, Al, a climate factor, K, Ca, Fe, and Mg as the minimum number of variables which best account for the species distributions. Sedge distributions within this region are determined primarily by gradients of shade and alkalinity/base cations. A comparison with other studies from boreal North American peatlands reveals that ecological requirements can differ across a sedge species' range.