Plankton metacommunities in floodplain wetlands under contrasting hydrological conditions

PTACNIK, ROBERT; CHAPARRO, GRISELDA; O'FARRELL, INÉS; HEIN, THOMAS; HORVÁTH, ZSÓFIA

FRESHWATER BIOLOGY (PRINT)

WILEY-BLACKWELL PUBLISHING, INC

Lugar: Londres; Año: 2018 vol. 63 p. 380 - 391

0046-5070

Abstract1. Species diversity is affected by processes operating at multiple spatial scales,although the most relevant scales that contribute to compositional variation andthe temporal shifts of the involved mechanisms remain poorly explored. Westudied spatial patterns of phytoplankton, rotifers and microcrustacean diversityacross scales in a river floodplain system of the Danube in Austria under contrastinghydrological conditions (post-flood versus low water level).2. The species turnover between water sections (b2) and between wetlands (b3)was the major components of regional diversity for all studied groups, with speciesturnover between habitats (b1) as a minor contributor. b1 diversity and b2diversity were lower than expected by chance in most cases, suggesting thatcommunities are more homogeneous than expected at these scales. b3 diversitywas higher than expected by chance in many cases, indicating more distinct communitiesat the wetland level. Patterns were highly similar under different hydrologicalconditions, indicating no major immediate effect of flood events.3. Local environmental and spatial factors were similarly important in structuring phytoplankton,rotifer and microcrustacean communities in both hydrological conditions.Relevant environmental factors were spatially structured in post-flood conditionsespecially between sections, suggesting flood-driven homogenisation within thewetlands. Under low water level, spatial structuring of environment decreased andpure environmental factors gained relevance for phytoplankton and rotifers.4. Our results suggest that although b2 diversity between water sections is a major componentof regional diversity, long-term spatial processes responding to connectivity acrossthe wetland structure phytoplankton, rotifer and microcrustacean communities. Aquaticsections within the limited spatial extent of the remaining floodplain areas appear morehomogeneous than expected probably due to flood recurrence over the years.5. These results highlight that adequate planning of restoration and conservationstrategies of floodplain wetlands should consider environmental heterogeneitytogether with long-term spatial processes.