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Influence of habitat structure and conditions in floodplain forests on mollusc assemblages

Kappes H., Kopeć D., Sulikowska-Drozd A.

Polish Journal of Ecology

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2014

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Vol. 62, nr 4

739--750

EN

Alder floodplain forests are a rare and threatened forest type in Europe. These forests can be very rich in mollusc species. The intermediate disturbance hypothesis predicts that species richness should peak at intermediate inundation frequency, that is, at intermediate elevation above the river level. We additionally hypothesized that constantly high soil moisture can distort the usually positive correlation between the amounts of downed deadwood and snail richness, and that tree stems might be more favourable than deadwood because their vertical structure provides a better refuge during inundation events. To this end, we sampled molluscs from a core area of 20 × 20 m from eight alluvial forests with black alder in the surroundings of Łódź, Central Poland. In each core area, substrate was collected from eight random plots (0.25 m2 each). We also recorded soil pH, vascular plant species and mosses diversity, along with other structural variables. Plant indicator values were calculated according to Ellenberg. Soil quality (amongst others: soil pH, reactivity value, nutrient and moisture availability) decreased with increasing elevation above the river level. In the plot samples, we found a total of 18,497 individuals from 52 species. Mollusc species richness dropped stronger than densities with an increasing elevation above the river level. Main influences on mollusc richness and abundance originated from positive correlations with soil pH and moisture. An additional hand sampling campaign on tree stems and deadwood items in the core area revealed that coarse woody debris items on average carried twice as many individuals as did tree stems. Deadwood and tree stems supported similar numbers of snail species per item, but beta-diversity was higher on deadwood. Consequently, Jackknife 2 predicted that deadwood is utilized by about 46 species, whereas tree stems only support about 39 species. Our results indicate (1) that mollusc richness peaks at low elevations above normal water level in this type of forest, (2) that intact hydrological regimes are associated with high soil quality and mollusc biodiversity, and (3) suggest that coarse woody debris adds resources, refuges and a dispersal agent for the alder forest floor fauna.

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The late Silurian-Middle Devonian long-term eustatic cycle as a possible control on the global generic diversity dynamics of bivalves and gastropods

Ruban Dmitry A.

Geologos

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2013

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Vol. 19, No. 3

193--200

EN

A long-term eustatic cycle (fall and subsequent rise of the global sea level) embraced the late Silurian-Middle Devonian time interval. Potentially, these sea-level changes could drive global biodiversity. The stratigraphic ranges of 204 bivalve genera and 279 gastropod genera included into the famous Sepkoski database allow reconstructing changes in the total diversity and the number of originations and extinctions of these important groups of marine benthic macro- -invertebrates during this interval. None of the recorded parameters coincided with the long-term global sea-level cycle. It cannot be not excluded, however, that the global sea-level changes did not affect the regions favourable for bivalve and gastropod radiation because of regional tectonic mechanisms; neither can it be excluded that the eustatic control persisted together with many other extrinsic and intrinsic controls. Interestingly, the generic diversity of gastropods increased together with a cooling trend, and vice versa. Additionally, the Ludlow, Eifelian, and Givetian biotic crises affected, probably, both fossil groups under study. There was also a coincidence of the relatively high bivalve generic diversity, initial radiation of gastropods and the entire biota, and the diversification of brachiopods with the Early Devonian global sea-level lowstand, and this may be interpreted as evidence of a certain eustatic control on the marine biodiversity.

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Olenekian (Early Triassic) fossil assemblage from eastern Julian Alps (Slovenia)

Kolar-Jurkovšek T., Vuks V. J., Aljinović D., Hautmann M., Kaim A., Jurkovšek B.

Annales Societatis Geologorum Poloniae

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2013

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Vol. 83, No. 3

213--227

EN

New palaeontological and sedimentological data from the Lower Triassic strata of the eastern Julian Alps in Slovenia are presented., They are unusual for the Early Triassic of the Alps in representing a relatively deeper, unrestricted marine (mid-ramp) setting. There are two basic microfacies types in the section investigated (types A and B), which are organized as couplets with coarse-grained tempestitic deposits (microfacies A), overlain by laminated or bioturbated lime mudstones and/or marls (microfacies B), frequently containing ammonoids. This pattern is interpreted as storm deposition with occasional winnowing of bottom sediments and the formation of coarse-grained skeletal deposits (lags), followed by the slow settling of suspended particles, when the storm waned, in addition to background deposition. Dominantly lime mud deposition and the presence of ammonoids indicate deposition on a more distal, deeper ramp with an unrestricted connection to the open sea. Intense reworking of bottom skeletal-rich sediment and accumulation of storm lags suggest deposition above the storm wave base, possibly in a wide low-energy mid-ramp environment. Faunas from such settings have been reported relatively rarely from the Early Triassic of the Alps. The macrofauna contains ammonoids, bivalves and gastropods, whereas the microfauna is represented by foraminifer tests and conodont elements; rare fish remains also occur. In the foraminifer assemblages, species of Ammodiscus, Hoyenella, Glomospirella dominated, corresponding to the widespread “Glomospira-Glomospirella” foraminifer community, with some miliolids and nodosariids. The conodont fauna is characterized by Triassospathodus hungaricus (Kozur et Mostler), indicating an early Spathian (Olenekian) age. The fossil assemblage highlights the wide distribution of Early Triassic taxa in the Tethys and facilitates its worldwide correlation. Its relatively low diversity by comparison with shallow marine settings is interpreted as an evolutionary proximal-distal trend in the wake of the end-Permian mass extinction. Re-diversification first occurred in nearshore settings and expanded into deeper/distal marine environments through geological time.

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Faunal dynamics of gastropods in the Bathonian (Middle Jurassic) ore-bearing clays at Gnaszyn, Kraków-Silesia Homocline, Poland

Kaim A.

Acta Geologica Polonica

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2012

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Vol. 62, no. 3

367-380

EN

The succession of gastropods in the Gnaszyn section is quite monotonous and shows significant changes only in the proximity of concretion layers, at least partially because of diagenetic reasons. Otherwise, the section is dominated by gastropods (cylidrobullinids, bullinids, and mathildids) most of which preyed probably on sedentary organisms (polychaetes and/or coelenterates) that possibly flourished on the sea bottom at that time. The other groups of gastropods are represented by larval or juvenile shells. Their presence shows that the environmental conditions that were probably unfavourable for gastropods living directly on the sea bottom most likely because of a soupy substrate consistency, possible oxygen deficiency near the sediment-water interface and/or oxygen content fluctuations. Adult and/or subadult individuals of these gastropods occur only in the higher part of the section, reflecting a time when these conditions improved. A new heterostrophic gastropod species, Promathildia gedli, is described.

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Faunal dynamics of bivalves and scaphopods in the Bathonian (Middle Jurassic) ore-bearing clays at Gnaszyn, Kraków-Silesia Homocline, Poland

Kaim A., Sztajner P.

Acta Geologica Polonica

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2012

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Vol. 62, no. 3

381-395

EN

The environment at the Gnaszyn section - as deduced from bivalve and scaphopod dynamics - was controlled by the substrate consistency and possibly oxygen deficiency near the sediment-water interface and/or oxygen content fluctuations. The middle part of the section dominated by nuculoid and corbulid bivalves and Laevidentalium-type scaphopods probably reflects a soupy substrate and possibly oxygen deficiency in the sediment. Slightly coarser and better-oxygenated silts in the upper and lower parts of the section offered a less soupy substrate consistency, allowing the development of communities dominated by astartids, byssate bivalves, and Dentalium- and Plagioglypta-type scaphopods.

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Fauna z osadów plejstoceńskich w stanowiskach Sucha Wieś (Pojezierze Ełckie) i Czarnucha (Równina Augustowska), północno-wschodnia Polska

Skompski S.

Biuletyn Państwowego Instytutu Geologicznego

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2009

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nr 435

85--95

PL

Do badań faunistycznych wykorzystano próbki osadów pobranych z otworu wiertniczego Sucha Wieś (Pojezierze Ełckie) z głębokości 153,60-178,00 m oraz z otworu wiertniczego Czarnucha (Równina Augustowska) z głębokości 96,05-118,85 m. Z badanej serii osadów jeziorno-bagiennych opisano szczątki różnych grup zwierząt: ślimaków (Gastropoda), małży (Bivalvia), małżoraczków (Ostrazoda), ryb (Pisces), chrząszczy (Coleoptera) i innych. Do określenia wieku osadów, szczególnie przydatne okazały się mięczaki (ślimaki i małże) oraz małżoraczki. Na podstawie obecności ślimaka Lithoglyphus jahni oraz małżoraczka Scottia browniana uznano, że osady nie mogą być młodsze od interglacjału mazowieckiego.

EN

Samples collected from the Sucha Wieś borehole (Ełk Lakeland) from a depth interval of 153.60-178.00 and from the Czarnucha borehole (Augustów Plain) from a depth interval of 96.05-118.85 m were analysed for faunal content. The lacustrine-marsh deposits contain fragments of various animals including gastropods, bivalves, ostracods, fish, Coleoptera and others. Especially important for age determinations are moluscs (gastropods and bivalves) and ostracods. The presence of Lithoglyphus jahni (gastropod) and Scottia browniana (ostracod) indicates that the deposits cannot be younger than the Mazovian Interglacial.

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Shallow-water gastropods from Late Oxfordian sands in Kłęby (Pomerania, Poland)

Grundel J., Kaim A.

Acta Geologica Polonica

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2006

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Vol. 56, no. 2

121-157

EN

The Upper Oxfordian shell-bearing ferruginous sands from Kłęby in Pomerania (northwestern Poland) provide a rich and relatively well-preserved shallow-water gastropod fauna that has been known in the literature since the monograph by SCHMIDT (1905). A review of SCHMIDT.s collection and newly collected material confirms the distinctiveness of the assemblage from contemporaneous faunas in neighbouring areas. We identified 27 species belonging to 21 genera, with two species not attributed to generic level. Seven species introduced by SCHMIDT(1905) are re-described in detail, with the types being illustrated. They are: Gerasimovcyclus lorioli (Eucyclidae), Proconulus coelotropis, P. viadrinus (Proconulidae), Pseudomelania laeviuscula (Pseudomelaniidae), Katosira anaroides (Zygopleuridae), Gordenella ommerana (Gordenellidae), and Sulcoactaeon viadrinus (Bullinidae). We also described three new species: Ataphrus marschmidti (Ataphridae), Shurovites dmochae (Cryptaulacidae), and Ceritellopsis huckriedei (Cylindrobullinidae). The gastropod fauna from Kleby is dominated by shallow-water species of cerithioids (Exelissa distans, Rhynchocerithium limaeformeand Shurovites dmochae), the rissoid Rissoa valfini, the eucyclid Eucycloscala cf. augur, and the ataphrid Falsataphrus kljasmiensis.