Fungal ecology and succession on <i>Phragmites australis</i> in a brackish tidal marsh. I. Leaf sheaths

Direct observation of fungal succession and community development on leaf sheaths of Phragmites australis have been studied over a period of 19 months in a brackish tidal marsh of the river Scheldt (The Netherlands). Seventy-seven taxa were identified: 33 ascomycetes (43%); 31 coelomycetes (40%); 9 hyphomycetes (12%) and 4 basidiomycetes (5%). Four microhabitats were screened, the top, middle and basal communities along the vertical axis of standing reed shoots and a community in the litter layer. Fungal community structure analyzed by multivariate analysis showed that all microhabitats are characterised by different mycota. Detrended correspondence analysis (DCA) of leaf sheath samples suggests the importance of a spatial separation (microhabitat) in explaining species variation between samples. Within each of those microhabitats DCA indicated a specific temporal pattern (succession). Fungal succession (community development) was described by a sequence of three phases in fungal sporulation. For the different microhabitats and all successional stages indicator species were assigned. The importance of screening host plants in situ and the use of indicator species analysis for fungal communities is addressed. The effect of seasonality on fungal succession is discussed