Zooplankton of the European soda pans: Fauna and conservation of a unique habitat type

Abstract

Despite the high conservation value of intermittent soda pans, these habitats were mostly targeted by small‐scale studies and little is known about their microscopic fauna. We sampled all the remaining 110 representatives of this habitat type (including recently restored ones) in Europe in an area covering approximately 125 000 km2. We analyzed spring and summer zooplankton species composition including rotifers, copepods, and cladocerans. We found 105 Rotifera, 26 Cladocera, and 26 Copepoda taxa, with local species richness ranging between 1 and 38 taxa. Alpha diversity was comparable in the two main groups (Rotifera, Crustacea), while beta and gamma diversity was higher in rotifers. The most frequently occurring zooplankters were crustaceans, while rotifer taxa were rarer as the most frequent species inhabited less than half of the pans. Dominance of the natronophilic Arctodiaptomus spinosus proved to be a reliable indicator for high quality soda pans. We concluded that the most typical soda pan zooplankton communities developed by early summer, in the concentrated pans, thus we would suggest considering this period as a reference for ecological state monitoring, and especially for evaluating the success of soda pan rehabilitations or reconstructions with the help of zooplankton. Based on these criteria, restorations could be considered only moderately successful.

Habitat loss over six decades accelerates regional and local biodiversity loss via changing landscape connectance

“…In 2009 and 2010, we re‐sampled all of these sites (Tóth et al . ). We randomly collected 20 litres of water from the open water of the pans, and sieved it through a plankton net with a mesh size of 30 μm.…”

Environmental constraint of intraguild predation: Inorganic turbidity modulates omnivory in fairy shrimps

“…In the predatory feeding tests, two typical members of soda pan zooplankton communities were used Tóth et al, 2014): a copepod (A. spinosus, 20 individuals in 70 ml) and a rotifer (B. asplanchnoidis, 100 individuals in 70 ml). In the predatory feeding tests, two typical members of soda pan zooplankton communities were used Tóth et al, 2014): a copepod (A. spinosus, 20 individuals in 70 ml) and a rotifer (B. asplanchnoidis, 100 individuals in 70 ml).…”

“…Anostracans can reach high densities in their habitats (Daborn, 1977;Horváth, Vad, Vörös, et al, 2013b;Vanschoenwinkel, Brendonck, Pinceel, Dupriez, & Waterkeyn, 2013; and they act both as competitors and predators of smaller zooplankton (Jocque, Vanschoenwinkel, & Brendonck, 2010;Lukić et al, 2018;Waterkeyn et al, 2011), which suggests a high impact on the zooplankton community. Moreover, anostracans disappear before temporary ponds dry out, while many zooplankton species occur throughout the whole wet season (Horváth, Vad, Vörös, et al, 2013a;Jocqué, Riddoch, & Brendonck, 2007;Tóth et al, 2014;Vanschoenwinkel, Waterkeyn, et al, 2010), which overall provides a temporal refuge for zooplankton (Kratina et al, 2012). Moreover, anostracans disappear before temporary ponds dry out, while many zooplankton species occur throughout the whole wet season (Horváth, Vad, Vörös, et al, 2013a;Jocqué, Riddoch, & Brendonck, 2007;Tóth et al, 2014;Vanschoenwinkel, Waterkeyn, et al, 2010), which overall provides a temporal refuge for zooplankton (Kratina et al, 2012).…”

“…The zooplankton groups used in the experiments as food were also collected live on the field in the Seewinkel area (47°48′49.4″N 16°47′34.4″E) and cultivated in the laboratory during the experiments. In the predatory feeding tests, two typical members of soda pan zooplankton communities were used Tóth et al, 2014): a copepod (A. spinosus, 20 individuals in 70 ml) and a rotifer (B. asplanchnoidis, 100 individuals in 70 ml).…”

“…Even though B. orientalis hatches very early after inundation/ice break (Lukić, Vad, & Horváth, 2016;Petkovski, 1991), it is probably predominantly herbivorous in the early stages of its life (similar to other anostracans; Daborn, 1975;Fryer, 1983), which gives some time for zooplankton communities to establish at the beginning of the wet phase of their habitats. Moreover, anostracans disappear before temporary ponds dry out, while many zooplankton species occur throughout the whole wet season (Horváth, Vad, Vörös, et al, 2013a;Jocqué, Riddoch, & Brendonck, 2007;Tóth et al, 2014;Vanschoenwinkel, Waterkeyn, et al, 2010), which overall provides a temporal refuge for zooplankton (Kratina et al, 2012). In addition, anostracans do not feed on the largest zooplankton such as adult D. magna (they are only susceptible to anostracan predation in the earliest stages of their life, Lukić et al, 2018).…”