Specificity of zooplankton distribution in meteorite crater ponds (Morasko, Poland)

• Main Authors: Kuczyńska-Kippen N., Basińska A.M., Świdnicki K.
• Format: Article
• Language: English
• Published: EDP Sciences 2013-07-01
• Series: Knowledge and Management of Aquatic Ecosystems
• Subjects: astatic ponds; crustaceans; pond; rotifers; season; trophic conditions
• Online Access: http://dx.doi.org/10.1051/kmae/2013053

This study was conducted in order to define the most important factors responsible for the zooplankton community structure inhabiting four meteorite crater ponds, located near the city of Poznań (Poland). The functioning of the meteorite craters resembled that of other small water bodies, where seasonality, physical-chemical features (mainly chlorophyll a concentration, pH and conductivity) or biological parameters (lack of fish) structured zooplankton assemblages. Rotifer species richness and abundance were highest in the autumn (12 species and 5107 ind L-1 on average), while crustaceans prevailed in the summer (12 and 201, respectively). The dominating structure also depended on the season, with pelagic species occurring in the spring and autumn and mainly littoral species in the summer. Moreover, the temporary nature of the craters caused great differentiation in zooplankton among ponds and favoured organisms adapted to living in astatic reservoirs, e.g. bdelloids, Daphnia pulex or Macrocyclops viridis. The co-occurrence of a variable community of small crustaceans with large daphnids indicated the existence of an additional ecological niche – a thick layer of sediments. Despite the occurrence of adverse living conditions (oxygen deficiencies and periodic drying) and the eutrophic character of the waters, these ponds were a source of many rare species (e.g. Keratella paludosa), even in the status of dominants. Protective measures (a nature reserve) allowed the area of meteorite fall to remain quite natural, despite its location close to an urban area.