Life strategies of selected algae species along the habitat gradient on peat bogs

Abstract

Autecological studies on some selected algae species were conducted in 1998 and 1999 on transition mires and raised bogs situated in the water and peat-bog nature reserve "Dury" in the Wdecki Landscape Park. Apart from forms co-dominating at all studied sites, such as Penium silvae-nigrae f. parallelum or Anisonema ovale, also forms that occurred occasionally were selected for autecological studies, such as e.g. Tetmemorus brebissonii var. brebissonii occurring in summer, or Chroococcus turgidus connected with sites situated near the water table. From the literature data it appears that the selected algae species, perhaps with exception of Petalomonas sphagnophila, are cosmopolitan organisms, characteristic of oligotrophic raised bogs. Species such as Anisonema ovale and Penium silvae-nigrae, despite different nutrition methods and different life "strategies", have a similarly wide range of tolerance to changeable habitat parameters. They are eurytopic species, which can find their developmental optimum in all habitats. Chroococcus turgidus and Tetmemorus brebissonii are autotrophic species, which display certain characteristics corresponding to the K - strategy of development. They are stenotopic species connected with a highly hydrated habitat of low electrolytic conductivity and low concentration of biogenic substances. From the data presented in this paper, it appears that there exists a certain ecological group of algae adapted to life in raised bogs. It is a group, which finds its developmental optimum just on these habitats and which indeed deserves the term "sphagnum algae".