Bryophyte community composition and diversity are indicators of hydrochemical and ecological gradients in temperate kettle hole mires in Ohio, USA

Abstract

Peatlands are subject to increased pressure from environmental and land-use change, particularly in temperate regions such as the US Midwest. Bryophytes dominate the ground cover of peatlands and play a key role in their functioning. Effective management and restoration of degraded peatlands requires good understanding of their bryophyte communities, and how these are shaped by environmental conditions. Furthermore, bryophytes are sensitive indicators of environmental conditions. We monitored microhabitat characteristics (hydrology, hydrochemistry, abundance of vascular vegetation, microtopography) alongside bryophyte community composition in nine kettle hole mires in Ohio (USA). We found that the most important drivers of bryophyte community composition and diversity were water level and hydrochemistry. Sampling locations showing poor fen characteristics (high water level, pH and electrical conductivity) were associated with generalist pleurocarpous mosses (indicator species: Amblystegium serpens) and lower species richness. Where bog conditions prevailed, Sphagnum species dominated, and Sphagnum fallax and the liverwort Cephalozia sp. were indicator species.

Keywords

• hydrochemistry
• hydrology
• indicator species analysis
• peatland
• wetland