The Potential Influence of Short-term Environmental Variability on the Composition of Testate Amoeba Communities in Sphagnum Peatlands

摘要: Testate amoebae are a group of moisture-sensitive, shell-producing protozoa that have been widely used as indicators changes in mean water-table depth within oligotrophic peatlands. However, short-term environmental variability (i.e., sub-annual) also probably influences community composition. The objective this study was to assess the potential influence on composition testate amoeba communities Sphagnum-dominated and conditions, including hourly measurements relative humidity upper centimeter peatland surface, were examined throughout 2008 growing season at 72 microsites 11 peatlands Pennsylvania Wisconsin, USA. Relationships among communities, vegetation, water table, pH, an index (EVI), using nonmetric multidimensional scaling correlation analysis. Results suggest EVI with some taxa more abundant under highly variable conditions (e.g., Arcella discoides, Difflugia pulex, Hyalosphenia subflava) others when surface relatively stable Archerella flavum Bullinularia indica). magnitude experienced appears be primarily controlled by vegetation density. In particular, sites dense Sphagnum cover had lower values than loose-growing or dominated vascular plants and/or non-Sphagnum bryophytes. Our results information may inferred from previously recognized. Knowledge relationships between should lead detailed refined inferences.