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Alexey A. Kotov - One of the best experts on this subject based on the ideXlab platform.
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disproportion among Cladocera crustacea skeletal components in lake sediment taphocoenoses and significance with respect to two methods of sub fossil enumeration
Journal of Paleolimnology, 2021Co-Authors: Anton A Zharov, Andrey V Tchabovsky, Alexey A. KotovAbstract:Analysis of Cladocera (Crustacea: Branchiopoda) subfossil remains in lake sediments features prominently in paleolimnological studies. It is well known, however, that species composition in a taphocoenosis (assemblage of subfossil remains in sediments) does not represent perfectly that of the original living community (biocoenosis) from which it came. We analyzed the representation of different Cladocera skeletal components in sediments of 27 Russian water bodies to compare two methods of enumerating relative abundances of Cladoceran remains: (1) recording the number of most abundant fragments of each taxon to represent the number of individuals, and (2) recording each fragment of a taxon as belonging to an individual specimen. Overall, for all Cladoceran taxa and all water bodies sampled, proportions of different skeletal components differed from what would be expected based on those in live individuals. Carapaces were the most abundant component in 23 of 27 water bodies. Head shields were common, but predominated in only four samples, whereas postabdomens were rare, accounting for < 10% of the whole sample set. Several hypotheses are proposed to explain the different proportions of Cladoceran skeletal remains in sediment samples. Both methods for counting remains yielded similar relative abundance estimates for different taxa, which can be regarded as evidence that both methods are adequate, with some exceptions. For example, Alona affinis was represented by a relatively high portion of postabdomens, a component that for other taxa was usually poorly represented. In general, recording of the total number of skeletal components, as compared to using the most abundant fragment method (MAF), slightly overestimates the significance of some taxa in the community. Disproportionate preservation of different skeletal components among Cladoceran taxa does not compromise the results of Cladoceran-based paleoecological analyses using either counting method, but should be considered when interpreting results.
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mitogenomics of Cladocera branchiopoda marked gene order rearrangements and independent predation roots
Molecular Phylogenetics and Evolution, 2021Co-Authors: Boping Han, Henri J Dumont, Alejandro Martinez, Martin Schwentner, Diego Fontaneto, Alexey A. KotovAbstract:Cladocera (Crustacea: Branchiopoda) is a key group of invertebrates. Despite a long history of phylogenetic research, relationships within this group remain disputed. We here provide new insights based on 15 new mitochondrial genomes obtained from high-throughput sequencing (HTS) and 40 mitogenomes extracted from published HTS datasets. Together with 25 mitogenomes from GenBank, we generated a matrix of 80 mitogenomes, 44 of them belonging to Cladocera. We also obtained a matrix with 168 nuclear orthologous genes to further assess the phylogenetic result from mitogenomes based on published data and one new HTS data ofLeptodora. Maximum likelihood and Bayesian phylogenetic analyses recovered all Branchiopoda orders as monophyletic and supported a sister-group relationship between Anomopoda and Onychopoda, making the taxon Gymnomera paraphyletic and supporting an independent origin of predatory Haplopoda and Onychopoda. The nuclear phylogeny and topological tests also support Gymnomera as paraphyletic, and the nuclear phylogeny strongly supports a sister-group relationship between Ctenopoda and Haplopoda. We provide a fossil-calibrated time tree, congruent with a Carboniferous origin for Cladocera and a subsequent diversification of the crown group of Anomopoda, Onychopoda, and Ctenopoda, at least in the Triassic. Despite their long evolutionary history, non-Cladoceran Branchiopoda exhibited high mitogenome structural stability. On the other hand, 21 out of 24 gene rearrangements occurred within the relatively younger Cladocera. We found the differential base compositional skewness patterns between Daphnia s.s. and Ctenodaphnia, which might be related to the divergence between these taxa. We also provide evidence to support the recent finding that Spinicaudata possesses mitogenomes with inversed compositional skewness without gene rearrangement. Such a pattern has only been reported in Spinicaudata.
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a new species of the daphnia sinevi group crustacea Cladocera daphniidae from sakhalin island russian far east
Zootaxa, 2020Co-Authors: Petr G Garibian, Alexey A. KotovAbstract:Daphnia curvirostris species complex is a Cladoceran group (Crustacea: Cladocera) with maximum diversity in Eastern Palearctic. To date, several representatives of this complex are known from the Russian Far East. Here we describe a new species of the Daphnia sinevi species group from water bodies of Sakhalin Island. Morphology of its parthenogenetic females is similar to that in D. sinevi from the continental part of Asian Eurasia. However, we found diagnostic traits of D. sakhalinensis sp.nov. in morphology of the second pecten on postabdominal claw, armature of seta 2 on exopodite III, proportions of setae 1/ and 2 length on exopodite V, relative length of male rostrum and structure of the second pecten of male postabdominal claw. This work contributes to our full revision of the D. curvirostris species complex. Separation between continental and Sakhalin populations of D. sinevi group probably happened in Pliocene (about 5 MA) when Sakhalin began to separate from the mainland. However, we cannot exclude a version that populations of D. sakhalinensis sp.nov. appeared as a result of colonization of Sakhalin from the continent and further independent evolution of the island populations.
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phylogeography of daphnia magna straus crustacea Cladocera in northern eurasia evidence for a deep longitudinal split between mitochondrial lineages
PLOS ONE, 2018Co-Authors: Eugeniya I Bekker, D P Karabanov, Alexey A. Kotov, Yan R Galimov, Christoph R Haag, Tatiana V NeretinaAbstract:Species with a large geographic distributions present a challenge for phylogeographic studies due to logistic difficulties of obtaining adequate sampling. For instance, in most species with a Holarctic distribution, the majority of studies has concentrated on the European or North American part of the distribution, with the Eastern Palearctic region being notably understudied. Here, we study the phylogeography of the freshwater Cladoceran Daphnia magna Straus, 1820 (Crustacea: Cladocera), based on partial mitochondrial COI sequences and using specimens from populations spread longitudinally from westernmost Europe to easternmost Asia, with many samples from previously strongly understudied regions in Siberia and Eastern Asia. The results confirm the previously suspected deep split between Eastern and Western mitochondrial haplotype super-clades. We find a narrow contact zone between these two super-clades in the eastern part of Western Siberia, with proven co-occurrence in a single lake in the Novosibirsk region. However, at present there is no evidence suggesting that the two mitochondrial super-clades represent cryptic species. Rather, they may be explained by secondary contact after expansion from different refugia. Interestingly, Central Siberia has previously been found to be an important contact zone also in other Cladoceran species, and may thus be a crucial area for understanding the Eurasian phylogeography of freshwater invertebrates. Together, our study provides an unprecedented complete, while still not global, picture of the phylogeography of this important model species.
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the fossil record of the Cladocera crustacea branchiopoda evidence and hypotheses
Earth-Science Reviews, 2016Co-Authors: Kay Van Damme, Alexey A. KotovAbstract:Abstract Waterfleas (Crustacea: Branchiopoda: Cladocera) are among the most successful invertebrates in current freshwater ecosystems, occupying a wide range of niches worldwide. Cladocerans are an important component of the zooplankton, occur in high abundance, and show a marked degree of morphological diversification and species richness with over 700 extant species, in > 100 genera. Though this group is of prime importance in the global aquatic food chain, comparably little is known of its early evolution. Until recently Cladoceran evolutionary history has been clouded by a mixture of assumptions, erroneous fossil identifications and circular reasoning without context. Our knowledge of the Cladoceran fossil record and our understanding of freshwater palaeo-ecosystems and their communities have made important progress over the last decades but still need further analysis of Cladoceran palaeontological data and a discussion of molecular clock estimates. Here we present a critical review of the complete fossil record of the Cladocera including the first ever deep-time palaeolimnological framework for the group. Cladocera are key primary consumers whose evolution is crucial to the understanding of the Mesozoic Lacustrine Revolution that helped to shape aquatic ecosystems. The fossil record is placed in the context of major historical changes in the freshwater environment including the appearance of predator-prey relationships and niche availability that have impacted Cladocera evolution. The Cladocera exhibit a striking morphological stasis over millions of years yet they have overcome significant ecological shifts and they continue to show remarkable plasticity which have been the key to their survival and success in the present day.
Jørgen Olesen - One of the best experts on this subject based on the ideXlab platform.
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AN UPDATED PHYLOGENYOF THE CONCHOSTRACA — Cladocera CLADE (BRANCHIOPODA,DIPLOSTRACA) BY
2015Co-Authors: Jørgen OlesenAbstract:An updated phylogenetic analysis of the Conchostraca and Cladocera (Branchiopoda, Diplo-straca) is presented in response to a recently published critique of Olesen (1998). Some errors are corrected and some scorings are modi ed. Practically all earlier conclusions are supported. Among these are (1) monophyletic Diplostraca and Cladocera; (2) an uncertain status of the Conchostraca and Spinicaudata, probably they are both paraphyletic with respect to the Cladocera; (3) uncertain relationships between the four distinct taxa within the Cladocera, though some support was found for the Gymnomera (Haplopoda and Onychopoda). ZUSAMMENFASSUNG Als Antwort auf eine jüngst publizierte Kritik an Olesen (1998) wird eine aktualisierte phylo-genetischeAnalyse der Conchostracaund Cladocera (Branchiopoda,Diplostraca) präsentiert. Einige Fehler der früheren Analyse werden korrigiert, einige Merkmals-Kodierungen modi ziert. Prak-tisch alle Schlußfolgerungen werden erneut unterstützt, so 1. die Monophylie der Diplostraca und der Cladocera, 2. der unsichere Status der Conchostraca und der Spinicaudata, beide Taxa sind wahrscheinlichparaphyletisch,und 3. die unsicherenVerwandtschaftsbeziehungender vier höhere
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Molecular phylogeny of the Branchiopoda (Crustacea)--multiple approaches suggest a 'diplostracan' ancestry of the Notostraca.
Molecular Phylogenetics and Evolution, 2006Co-Authors: Jesper Stenderup, Jørgen Olesen, Henrik GlennerAbstract:The evolutionary history of Branchiopoda (Crustacea) traditionally has attracted considerable interest due to the diversity of the group. Recently molecular methods have been applied to the study of branchiopod systematics with some success, but central questions, such as the phylogenetic position of Laevicaudata and Notostraca, and the intrinsic Cladoceran phylogeny, remain unanswered. We examined the phylogeny of Branchiopoda by using two genes, mitochondrial 16S rRNA and nuclear 28S rRNA, which previously have seen little use for inferring branchiopod phylogeny. The number of ingroup taxa included was 42, representing all eight extant branchiopod orders. The data were analyzed using parsimony, maximum likelihood, and Bayesian Inference of phylogeny. Some higher-level taxa were supported in all analyses of the combined data: Phyllopoda, Cladoceromorpha, Cladocera, and Gymnomera. Other higher-level taxa were not supported in any trees: Diplostraca and Conchostraca. A case is made for a possible diplostracan ingroup position of Notostraca based on our data and on previously published molecular and morphological evidence. The recent discovery of a Devonian branchiopod, which is morphologically an intermediate between a notostracan and a ‘conchostracan’, is congruent with a diplostracan ancestry of Notostraca.
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on the ontogeny of leptodora kindtii crustacea branchiopoda Cladocera with notes on the phylogeny of the Cladocera
Journal of Morphology, 2003Co-Authors: Jørgen Olesen, Stefan Richter, Gerhard ScholtzAbstract:Leptodora kindtii, a large predaceous clado- ceran, is among the most deviant species of the Cladocera. Therefore, its phylogenetic position has traditionally proven difficult to determine. Its many peculiar features include, among others, long, stenopodous, forwardly di- rected trunk limbs, a posteriorly placed dorsal brood pouch, a tri-lobed lower lip, and a long, segmented abdo- men. This study describes the ontogeny of L. kindtii (Hap- lopoda), including general body proportions, appendages, the carapace, and other external structures in an attempt to facilitate the comparison of its aberrant morphology to that of other branchiopods. In general, the early embryos are similar to the early embryos of other Cladoceran taxa with respect to body shape and size and position and orientation of the early limb buds. Many of the unusual features of L. kindtii appear late in ontogeny. The cara- pace appears at an early stage as a pair of dorsolateral swellings in a position corresponding to the gap between the mandibles and the first pair of trunk limbs; it later becomes posteriorly transposed by a gradual fusion of its more anterior parts to the dorsal side of the thorax. The tri-lobed "lower lip," under the labrum of the late embryo and the adult, develops as a fusion of the first maxillae (lateral lobes) to an elevated sternal region behind the mouth (median lobe). The stenopodous, segmented trunk limbs in the adult develop from embryonic, elongate, sub- divided limb buds, similar to those seen in early stages of other branchiopods. Two conflicting possibilities for the phylogeny of the Cladocera, involving two different posi- tions of L. kindtii (Haplopoda), are discussed. Several characters support a sister-group relationship between the Haplopoda and Onychopoda. However, some charac- ters support the Anomopoda and Onychopoda as sister groups, leaving the Haplopoda outside this clade. In con- trast to recent suggestions, we prefer to retain the term "Cladocera" in its original sense as comprising the Hap- lopoda, Ctenopoda, Anomopoda, and Onychopoda. J. Mor- phol. 256:235-259, 2003. © 2003 Wiley-Liss, Inc.
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larval and post larval development of the branchiopod clam shrimp cyclestheria hislopi baird 1859 crustacea branchiopoda conchostraca spinicaudata
Acta Zoologica, 1999Co-Authors: Jørgen OlesenAbstract:The larval and post-larval development of Cyclestheria hislopi is examined by SEM. There are at least nine stages (excluding the adult) – six larval and three post-larval stages. The first four stages are passed within the egg-membrane. The larval and the post-larval phase are separated by a profound change in morphology that takes place between stages VI and VII. The larva shifts from a dorso-ventrally flattened ‘larval’ appearance up to stage VI to a laterally flattened, more ‘adult’ appearance from stage VII. New morphological data have been revealed by this study, including (1) a large and globular larval dorsal organ; (2) the carapace starts its development from the segments of the first and second maxillae; (3) the anterior ramus of the second antenna in adult Cyclestheria hislopi is the endopod, and the posterior ramus the exopod. Direct development of the brood in Cyclestheria hislopi– unique among conchostracans – is compared with that of the Cladocera. If Cyclestheria is the sister group to the Cladocera, as favoured in this work, the classical neoteny theory of the Cladocera must be reconsidered, as there is no particular similarity between any adults of the Cladocera and any of the larval stages of Cyclestheria. It is suggested that Cyclestheria displays the type of development present in a Cladoceran ancestor. A comparison between Cyclestheria and the Upper Cambrian ‘Orsten’ fossil Rehbachiella kinnekullensis reveals a remarkable similarity in the endite morphology of the trunk limbs.
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External morphology of the male of Cyclestheria hislopi (Baird, 1859) (Crustacea, Branchiopoda, Spinicaudata), with a comparison of male claspers among the Conchostraca and Cladocera and its bearing on phylogeny of the ‘bivalved’ Branchiopoda
Zoologica Scripta, 1996Co-Authors: Jørgen Olesen, Joel W Martin, Ewald W. RoesslerAbstract:The adult male of Cyclestheria hislopi, sole member of the spinicaudate conchostracan clam shrimp family Cyclestheriidae and a species of potential phylogenetic importance, is described for the first time. Several previously unknown features are revealed. Among these are (1) the morphology of the dorsal organ, which is roughly similar in shape to the supposedly homologous structure in other clam shrimps but bears a relatively large, centrally located pore unique to the species; (2) an anterior cuticular pore presumably leading to the ‘internal’ space surrounding the compound eyes, and thereby homologous to the same pore in other clam shrimps and in the Notostraca; (3) the spination and setation of the antennae and thoracopods, and (4) the mature male first thoracopods (claspers). The male claspers are paired and essentially equal in size and shape on right and left sides of the body. The second pair of thoracopods are not modified as claspers, a situation different from all other spinicaudate families but shared (plesiomorphic we propose) with the laevicaudatans and most Cladocerans. The claspers bear a field of special spine-like setae on the extremity of the ‘palm’; this setal type, previously unrecognized, is unique to Cyclestheria. The palm of the clasper also bears two palps (one very small), as in other conchostracan species (both laevicaudatans and spinicaudatans). The movable finger of the clasper, modified from the thoracopod endopod, bears a row of long setae along its outer extremity, also unique. Cyclestheria exhibits a mixture of characters, some unique and others typical of the Spinicaudata (Conchostraca). Cladoceran clasper types are briefly reviewed. as are the claspers in the Spinicaudata and Laevicaudata (Conchostraca). Morphology of the clasper of Cyclestheria shows typical spinicaudate characters. It is suggested that claspers on the first thoracopods may be a synapomorphy for the Conchostraca and the Cladocera. The possible role of Cyclestheria or a Cyclestheria-like ancestor in Cladoceran phylogeny is briefly discussed in light of recent suggestions (Martin and Cash-Clark, 1995) of Cladoceran monophyly and possible ancestral relationships with this genus. Some possibilities concerning the phylogenetic position of Cyclestheria–either as a sister group to the rest of the Spinicaudata or as a sister group to the Cladocera—are discussed.
Ewald W. Roessler - One of the best experts on this subject based on the ideXlab platform.
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External morphology of the male of Cyclestheria hislopi (Baird, 1859) (Crustacea, Branchiopoda, Spinicaudata), with a comparison of male claspers among the Conchostraca and Cladocera and its bearing on phylogeny of the ‘bivalved’ Branchiopoda
Zoologica Scripta, 1996Co-Authors: Jørgen Olesen, Joel W Martin, Ewald W. RoesslerAbstract:The adult male of Cyclestheria hislopi, sole member of the spinicaudate conchostracan clam shrimp family Cyclestheriidae and a species of potential phylogenetic importance, is described for the first time. Several previously unknown features are revealed. Among these are (1) the morphology of the dorsal organ, which is roughly similar in shape to the supposedly homologous structure in other clam shrimps but bears a relatively large, centrally located pore unique to the species; (2) an anterior cuticular pore presumably leading to the ‘internal’ space surrounding the compound eyes, and thereby homologous to the same pore in other clam shrimps and in the Notostraca; (3) the spination and setation of the antennae and thoracopods, and (4) the mature male first thoracopods (claspers). The male claspers are paired and essentially equal in size and shape on right and left sides of the body. The second pair of thoracopods are not modified as claspers, a situation different from all other spinicaudate families but shared (plesiomorphic we propose) with the laevicaudatans and most Cladocerans. The claspers bear a field of special spine-like setae on the extremity of the ‘palm’; this setal type, previously unrecognized, is unique to Cyclestheria. The palm of the clasper also bears two palps (one very small), as in other conchostracan species (both laevicaudatans and spinicaudatans). The movable finger of the clasper, modified from the thoracopod endopod, bears a row of long setae along its outer extremity, also unique. Cyclestheria exhibits a mixture of characters, some unique and others typical of the Spinicaudata (Conchostraca). Cladoceran clasper types are briefly reviewed. as are the claspers in the Spinicaudata and Laevicaudata (Conchostraca). Morphology of the clasper of Cyclestheria shows typical spinicaudate characters. It is suggested that claspers on the first thoracopods may be a synapomorphy for the Conchostraca and the Cladocera. The possible role of Cyclestheria or a Cyclestheria-like ancestor in Cladoceran phylogeny is briefly discussed in light of recent suggestions (Martin and Cash-Clark, 1995) of Cladoceran monophyly and possible ancestral relationships with this genus. Some possibilities concerning the phylogenetic position of Cyclestheria–either as a sister group to the rest of the Spinicaudata or as a sister group to the Cladocera—are discussed.
Liisa Nevalainen - One of the best experts on this subject based on the ideXlab platform.
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Sedimentary Record of Cladoceran Functionality under Eutrophication and Re-Oligotrophication in Lake Maggiore, Northern Italy
MDPI AG, 2018Co-Authors: Liisa Nevalainen, Meghan Brown, Marina MancaAbstract:We examined fossil Cladocera (Crustacea) communities and their functional assemblages in a ~60-year sediment record from Lake Maggiore, northern Italy. Our main objective was to document the response of aquatic community functioning to environmental stress during eutrophication (1960–1985) and recovery (post-1985), and to identify environmental controls on Cladoceran functionality. Of the functional groups, large filter feeders and oval epibenthos thrived prior to eutrophication (reference conditions pre-1960) and globular epibenthos and small filter feeders increased during eutrophication and as the lake recovered. Multivariate analyses suggested that bottom-up controls (i.e., total phosphorus) were important for shaping functional assemblages but taxonomic community changes were likely related to top-down control by predators, particularly the predaceous Cladoceran Bythotrephes longimanus. Functional diversity (FD) was higher and Daphnia ephippia length (DEL) larger during the reference and early eutrophication periods and decreased during eutrophication and recovery. Both FD (high) and DEL (large) were distinct during reference period, but were similar (FD low, DEL small) between the eutrophication and recovery periods. The functional attributes and the assemblages did not recover post-eutrophication, suggesting that the system exhibited a clear shift to low FD and dominance of small filterers. Cladoceran functionality appears to be related to fundamental ecosystem functions, such as productivity, and may thus provide insights for long-term changes in ecological resilience
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late weichselian and holocene record of the paleoenvironmental changes in a small river valley in central poland
Quaternary Science Reviews, 2016Co-Authors: Dominik Pawlowski, Liisa Nevalainen, Tomi P Luoto, Ryszard K Borowka, Grzegorz Kowalewski, Krystyna Milecka, Daniel Okupny, Julita Tomkowiak, Tomasz ZielinskiAbstract:Abstract: The developmental history, from the Oldest Dryas to the Late Holocene, of a paleolake and mire located in a river valley in Central Poland was studied using high-resolution records of pollen, macrofossils, Cladocera, sedimentology, and geochemistry from a 14 C dated sediment core. We inferred temperature and water level dynamics using Cladocerans and palynological and geochemical methods were employed to investigate natural fluvial activity, particularly for these elements that are difficult to find through sedimentological methods. Our research demonstrates how climate fluctuation in the Late Glacial and Holocene periods influenced the development of a paleolake and mire in a small river valley and shows the importance of long-term research to establish hydroclimatic conditions in biogenic sediments. We propose that water level fluctuations were important in modifying biotic assemblages. The results of our multiproxy analysis clearly suggest that the main driver of changes in aquatic and terrestrial ecosystems, as well as in geomorphological processes in the valley, was climate: reconstructed temperatures generally follow the known trends, showing an increase at the beginning of the Bolling, Allerod, and Holocene and a decrease at the beginning of the Oldest and Younger Dryas. Similarly, periods of water level increase are synchronous with climatic changes. However, the local environmental forces were a significant factors affecting biotic diversity in the studied time span. Fish predation, macrophyte structure, pH, and calcium content partly influence the results of the Cladoceran-based water depth reconstruction in particular. Interestingly, the Cladoceran-inferred summer temperature reconstruction for Pawlowa appear realistic. Although the temperature trends can be considered reliable, our results indicate the important role of local factors which control the species composition of the subfossil assemblages.
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role of terrestrial carbon in aquatic uv exposure and photoprotective pigmentation of meiofauna in subarctic lakes
Freshwater Biology, 2015Co-Authors: Liisa Nevalainen, Tomi P Luoto, Marttiina V Rantala, Annukka Galkin, Milla RautioAbstract:Summary Aquatic organisms are adversely influenced by ultraviolet radiation (UV) and utilise photoprotective strategies, including pigmentation. We examined UV-protective melanin pigmentation of aquatic meiofauna (Cladocera) in relation to the UV exposure across 25 tree line lakes in Finland to address the potential effects of increased UV and altered input of UV-screening terrestrial dissolved organic carbon (DOC) on aquatic organisms. Bio-optical parameters, including concentration of DOC, the coloured dissolved organic matter (CDOM) fraction, a suite of carbon quality indices and chlorophyll a, were analysed from lake water, and their role in controlling underwater UV environment (measured as diffuse UV attenuation coefficient Kd at 305 and 340 nm) was examined. Cladoceran (Alona affinis) carapaces were extracted from the surface sediments, and their melanisation was assessed with spectroscopic UV-visible light absorbance measurements. DOC, CDOM and specific UV absorbance (SUVA) had strong positive relationships with the attenuation of UV in the lakes, suggesting that terrestrial organic carbon controls underwater UV exposure in the examined lakes. The absorbance measurements indicated the presence of melanin in the Cladoceran carapaces, the degree of melanisation varying strongly among the lakes. Melanisation had significant relationships with SUVA and fluorescence index (FI). It was higher in lakes with low SUVA and high FI, indicating that Cladocerans exhibit strong melanisation in lakes with low contribution of UV-attenuating allochthonous DOC (i.e. high UV exposure). The results suggest that Cladoceran meiofauna respond to UV by utilising photoprotective pigmentation and that the degree of pigmentation is affected by site-specific underwater UV exposure, which is ultimately controlled by UV-attenuating DOC of terrestrial origin. Although Cladoceran meiobenthos are able to adapt to varying underwater UV doses, climate change with its multiple consequences on hydrology, limnology and catchment vegetation in the tree line zone may cause major changes in underwater UV environment for the organisms to adapt.
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spatio temporal distribution of sedimentary Cladocera crustacea branchiopoda in relation to climate
Journal of Biogeography, 2013Co-Authors: Liisa Nevalainen, Tomi P Luoto, Seija Kultti, Kaarina SarmajakorjonenAbstract:Aim Spatial and temporal variations in the composition of freshwater invertebrate assemblages may be useful indicators of past climate change and help us to predict species responses to future climate change. The objective of this study was to understand the relationship between climate variables and fossil Cladocera assemblages in lake sediments along a contemporary climate gradient from hemiboreal to subarctic ecoregions in Finland and throughout the Holocene climate succession. Location Seventy-three small shallow lakes across a climate gradient from hemiboreal (60° N) to subarctic (70° N) Finland and a case study lake, Lake Arapisto, in south boreal Finland. Methods Fossil Cladoceran assemblages were analysed from the surface sediments of 73 lakes to investigate their association with climate, using ordination techniques (detrended correspondence analysis and redundancy analysis) and generalized linear modelling (GLM). The long-term variation of the abundance of specific climate-sensitive Cladoceran species was then analysed in a sediment core from a boreal lake and compared with a chironomid-based Holocene temperature reconstruction from an adjacent lake. Results Mean July air temperature was identified as a significant variable in explaining species distribution across the spatial climate gradient. This result, together with GLMs that recognized several climate-sensitive species, indicates that certain Cladoceran taxa may be useful indicators of climate. For example, the planktonic Bosmina longirostris and the phytophilous Graptoleberis testudinaria were more abundant in the warm southern lakes, in contrast to the benthic Alona affinis and Alona intermedia, which were typical for the cold northern lakes. The surface-sediment inferences were supported by the core analysis from Lake Arapisto, because species associated with cold lakes increased in abundance during the cold early Holocene, and species associated with warm lakes thrived during the Holocene Thermal Maximum and Anthropocene. Main conclusions The spatio-temporal distribution of Cladocera is regulated by regional climate, and therefore the species–climate relationships in space and time can be used to interpret past, present and future distributional patterns under a changing climate.
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Identification of subfossil remains of Cladocerans Latona setifera, Diaphanosoma brachyurum AND Holopedium gibberum
Studia Quaternaria, 2005Co-Authors: Liisa Nevalainen, Kaarina Sarmaja-korjonenAbstract:The preservation of chitinous outer body parts of Cladocera is mostly selective, except in two families, the planktonic Bosminidae and the littoral Chydoridae. In addition, at least some body parts of several other genera and taxa preserve but many of them have not been widely identified. The aim of the article is to present photographs and line drawings of the postabdomen and the postabdominal claws of Holopedium gibberum, together with the postabdominal claws of Latona setifera and Diaphanosoma brachyurum for use of Cladoceran analysts. In analysis of subfossil remains pictures and descriptions of separate body parts make the identification more reliable. It is hoped that with increasing knowledge about remains of as many taxa as possible, a more complete picture of the past Cladoceran assemblages can be obtained, together with a more precise assessment of past ecological conditions, such as pH and trophic state.
István Gyulai - One of the best experts on this subject based on the ideXlab platform.
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community response of Cladocera to trophic stress by biomanipulation in a shallow oxbow lake
Water, 2019Co-Authors: Csaba Berta, János Korponai, Bela Tothmeresz, Marta Wojewodka, Olga Augustyniuk, Boglarka Bertalanbalazs, Alex Sandor Nagy, Istvan Grigorszky, István GyulaiAbstract:Studying contemporary and subfossil Cladocera (Crustacea) communities, we explored the effect of top-down stressors on the Cladoceran communities; we are also interested in the coherence of the contemporary and subfossil communities. The studied Cibakhaza oxbow lake is in E Hungary, on the left-floodplain of the River Tisza; it is a large, long, and shallow oxbow lake. Three areas of the oxbow lake were distinguished based on the strength of top-down stress: protected area with low top-down stress, biomanipulated area with high top-down stress, and recreational area with moderate top-down stress. Altogether, we identified 28 taxa in the contemporary and subfossil communities in the oxbow lake. We found that the species number of the contemporary Cladocera communities was lower (protected area: 13; biomanipulated area: 9, and recreational area: 14) than in the subfossil communities (protected area: 20; biomanipulated area: 16, and recreational area: 14). Among the environmental variables, we observed differences between the protected and biomanipulated area, while the recreational area showed a transition. Species number, abundances, and Simpson diversity also showed the effect of the fish introduction. There were no differences in beta-diversity among the contemporary and subfossil Cladocera community. The non-metric multidimensional scaling (NMDS) ordination showed that the biomanipulated area in the case of the contemporary communities was separated from the other areas, while in the case of the subfossil communities, there was no separation according to top-down stress. Our results showed that the number of species of contemporary Cladocera communities was lower in each area (3–10; 3–9; 5–9) compared to the subfossil communities (6–17; 7–12; 8–12). However, the highest abundances were found in the biomanipulated area due to the appearance of small-sized Cladocera species. Our findings suggest that the effect of a short-time fish introduction is restorable when the oxbow lake has a protected part.
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reconstruction of flood events in an oxbow lake marotzugi holt tisza ne hungary by using subfossil Cladoceran remains and sediments
Advances in Oceanography and Limnology, 2016Co-Authors: János Korponai, István Gyulai, Mihály Braun, Csilla Kövér, István Papp, László ForróAbstract:Oxbow lakes are important components of the floodplain systems of lowland rivers. During flood events, oxbows are connected with the main river channel, and behave as lotic systems, while during inter-flood periods, these lakes can be considered as lentic ecosystems. Rivers are generally poor in planktonic organisms and their sediments contain scarce biological remains in comparison to lentic water ecosystems. However, due to their alternating running and standing water regime, sedimentary biological remains of oxbow lakes can be used as proxies for tracking changes of past hydrological regimes. In this study we investigated how Cladoceran communities respond to flood events, and whether flood events can be recognized by community analysis of Cladoceran remains. A sediment core from Marotzugi-Holt-Tisza oxbow lake was analyzed for identification of past flood events based on changes in the subfossil Cladocera community. Floods were defined based on the proportion of fine sand (50 µm grain size) in the oxbow sediments. If the fine sand portion was 90% of total remains. Discriminant analysis on Cladoceran data confirmed that lotic and lentic hydrological stages were characterized by different Cladocera species associations. Bosmina longirostris, Chydorus sphaericus, Alona rectangula, Acroperus harpae, Leydigia leydigi, A. quadrangularis and A. nana were mainly responsible for the differences between lotic and lentic species assemblages. Our results revealed that Cladocera remains can be used to track changes in the hydrological regime of oxbow lakes.
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Reconstruction of flood events in an oxbow lake (Marótzugi-Holt-Tisza, NE Hungary) by using subfossil Cladoceran remains and sediments
PAGEPress Publications, 2016Co-Authors: János Korponai, István Gyulai, Mihály Braun, Csilla Kövér, István Papp, László ForróAbstract:Oxbow lakes are important components of the floodplain systems of lowland rivers. During flood events, oxbows are connected with the main river channel, and behave as lotic systems, while during inter-flood periods, these lakes can be considered as lentic ecosystems. Rivers are generally poor in planktonic organisms and their sediments contain scarce biological remains in comparison to lentic water ecosystems. However, due to their alternating running and standing water regime, sedimentary biological remains of oxbow lakes can be used as proxies for tracking changes of past hydrological regimes. In this study we investigated how Cladoceran communities respond to flood events, and whether flood events can be recognized by community analysis of Cladoceran remains. A sediment core from Marótzugi-Holt-Tisza oxbow lake was analyzed for identification of past flood events based on changes in the subfossil Cladocera community. Floods were defined based on the proportion of fine sand (50 µm grain size) in the oxbow sediments. If the fine sand portion was <3%, the water regime of the oxbow was considered as lentic, otherwise it was lotic. Both organic and pigment contents were significantly higher in the core sections deposited during lentic stages. Thirty-four Cladocera species were determined in this core, all common to littoral habitats of eutrophic shallow lakes in Hungary. One planktonic (Bosmina longirostris) and four chydorid species (Alona rectangula, Acroperus harpae, Alonella nana and Chydorus sphaericus) were dominant throughout the core and contributed >90% of total remains. Discriminant analysis on Cladoceran data confirmed that lotic and lentic hydrological stages were characterized by different Cladocera species associations. Bosmina longirostris, Chydorus sphaericus, Alona rectangula, Acroperus harpae, Leydigia leydigi, A. quadrangularis and A. nana were mainly responsible for the differences between lotic and lentic species assemblages. Our results revealed that Cladocera remains can be used to track changes in the hydrological regime of oxbow lakes.