197 research outputs found

    Molluscan and Vertebrate Successions from the Veľká Drienčanská Cave

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    Here we present a biostratigraphy of entrance deposits in the Veľká Drienčanská Cave based on molluscan and vertebrate successions in correlation with prehistoric pottery records. This corresponds to the final Last Glacial – Holocene time-span and reflects the following environmental history: the coexistence of open-country and woodland snail communities throughout the whole succession documents the persistence of high-diversity karsts parkland since the Late Glacial up to present, which has been supported by human activities since the Neolithic occupation. However, the molluscan succession shows a general agreement with the standard mid-European developmental pattern. The molluscan evidence is confirmed by vertebrate fossil finds

    K malakologické charakteristice mokřadů Kokořínska

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    FERTILIZATION OF VINE BY A 5-AMINOLEVULINIC ACID-BASED FERTILIZER AND ITS PROFITABILITY

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    In this work we investigated the effect of different doses of NPKS fertilizer added into the soil for nutrient contents in the soil, as well as the quantity and quality of grapes. During the vegetation of the vine, we tested the 5-aminolevulinic acid-based fertilizer (ALA). We summarize that higher doses of fertilizer added into soil caused higher amounts of available nutrients. During the vegetation of the vine an increase of ALA had a positive effect on the optimal balance of nutrients. Fertilization also increased the grape-vine yield, with the strongest effect (by 68%) observed due to the application of ALA during the vegetation period of the vine. Added fertilizers had a statistically significant influence on decreased sugar concentration in the grape-vine however the addition of fertilizer into the soil, mainly the application of ALA during vegetation of the vine (by 57%) had a positive effect on increase of the total content of sugar in the grape-vine, produced on 1 hectare. The year had a significant influence on the economical evaluation

    Nivní malakofauna povodí Úštěckého potoka a její vývoj během holocénu

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    This paper presents a research of floodplain mollusc assemblages of the Úštěcký Brook catchment basin (Elbe tributary, North Bohemia, Czech Republic). Altogether, 71 mollusc species (69 species of Gastropoda, 2 species of Bivalvia) were recorded in the study sites between 2007 and 2011, representing 29% of the total Czech malacofauna. The common forest species dominated (41% of all recorded species) and included some rare woodland species as Daudebardia rufa, Discus perspectivus, Macrogastra ventricosa, and Sphyradium doliolum. Rare wetland species protected by the NATURA system Vertigo angustior and endangered wetland species Vallonia enniensis were also found. The richest assemblages occurred on the upper part of the brook, while the lower part was very species poor due to agriculture land use in this fertile floodplain. A small calcareous moorland, situated in the northeastern vicinity of Úštěk Town (north Bohemia) includes a Holocene mollusc succession that was subdivided into three local mollusc zones: I – basal zone with marked numbers of Discus ruderatus, Vertigo geyeri and numerous aquatic taxa, II – with forest species including Platyla polita and III – dominated by open-ground and catholic species. Despite the specific conditions of the moorland habitat the succession largely corresponds with the standard developmental pattern of the mollusc fauna in the zone of mid-European uplands. Of particular interest is the developmental break reflected by the poor fauna in the layer 3. The malacofauna of the Úštěcký Brook can be used as a model of alluvial mollusc assemblages of the brook floodplain that is situated in the warm area of Central Europe with long-term history of agriculture land use

    Alpine Crossroads or Origin of Genetic Diversity? Comparative Phylogeography of Two Sympatric Microgastropod Species

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    The Alpine Region, constituting the Alps and the Dinaric Alps, has played a major role in the formation of current patterns of biodiversity either as a contact zone of postglacial expanding lineages or as the origin of genetic diversity. In our study, we tested these hypotheses for two widespread, sympatric microgastropod taxa – Carychium minimum O.F. Müller, 1774 and Carychium tridentatum (Risso, 1826) (Gastropoda, Eupulmonata, Carychiidae) – by using COI sequence data and species potential distribution models analyzed in a statistical phylogeographical framework. Additionally, we examined disjunct transatlantic populations of those taxa from the Azores and North America. In general, both Carychium taxa demonstrate a genetic structure composed of several differentiated haplotype lineages most likely resulting from allopatric diversification in isolated refugial areas during the Pleistocene glacial periods. However, the genetic structure of Carychium minimum is more pronounced, which can be attributed to ecological constraints relating to habitat proximity to permanent bodies of water. For most of the Carychium lineages, the broader Alpine Region was identified as the likely origin of genetic diversity. Several lineages are endemic to the broader Alpine Region whereas a single lineage per species underwent a postglacial expansion to (re)colonize previously unsuitable habitats, e.g. in Northern Europe. The source populations of those expanding lineages can be traced back to the Eastern and Western Alps. Consequently, we identify the Alpine Region as a significant ‘hot-spot’ for the formation of genetic diversity within European Carychium lineages. Passive dispersal via anthropogenic means best explains the presence of transatlantic European Carychium populations on the Azores and in North America. We conclude that passive (anthropogenic) transport could mislead the interpretation of observed phylogeographical patterns in general

    Damages caused by predation of invertebrates on the earliest development stages of fish

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    Cílem bakalářské práce bude zjistit do jaké míry je přítomnost bezobratlých predátorů pro raná stádia ryb nebezpečná a má vliv na míru jejich přežívání. Většina hospodářsky chovaných druhů ryb se do rybníků nasazuje ve stádiu váčkového plůdku a nedochází k předchozímu rozkrmování na vacích či jiných odchovných zařízeních s pozdějším vysazením již silnějšího rozkrmeného plůdku. V prvních dnech po nasazení dochází také k největším ztrátám, které mohou být způsobeny ať už nedostatečnou potravní nabídkou nebo zejména predací bezobratlými predátory. Mezi ně mohou patřit tzv. "dravé" buchanky, larvy vážek nebo vodních brouků, a i některé druhy vodních ploštic. Student v průběhu bakalářské práce uskuteční několik laboratorních pokusů na rozplavaném plůdku kaprovitých, případně i okounovitých ryb, které bude konfrontovat s dravci, tedy dravými larvami hmyzu, vodními plošticemi či buchankami. Na základě pokusů vyhodnotí potenciální nebezpečnost jednotlivých dravců vzhledem k plůdku ryb

    Branchiobdellidan population on alien species of crayfish in the Czech Republic

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    The thesis summarizes the current knowledge about the class Branchiobdellae including their anatomy, ecology and geographic distribution with respect to the presence of introduced species in Europe. Using samples of Branchiobdellidan obtained from two introduced species of crayfish caught in a pond near Čáslavice u Moravských Budějovic (signal crayfish, Pacifastacus leniusculus) and in Černíský stream (eastern crayfish, Orconectes limosus), two out of seven European species of Branchiobdellidan were identified, namely B. parasita with 100% presence in the eastern crayfish and 58.7% presence in the signal crayfish, and B. pentodonta with 41.3% presence. Based on data collected from the caught crayfish and samples of Branchiobdellidan, the individual weight of eastern crayfish was proved to influence the quantity and biomass of Branchiobdellidan on the body of crayfish (p<0.001), i.e. increased quantity and biomass of Branchiobdellidan was found on more robust specimens of crayfish, however the effect of gender was not statistically significant. With respect to the signal crayfish, a significant difference was observed in the quantity and biomass of Branchiobdellidan depending on the weight of the crayfish (p<0.001), and the influence of the gender of the crayfish was detected (p<0.001), i.e. the quantity and biomass of Branchiobdellidan was higher on the surface of male specimens of crayfish. The presence of eggs in some female signal crayfish had no significant effect on the quantity and biomass of Branchiobdellidan (p=0.052), however in combination with the weight, the influence of the presence or absence of eggs was proved (p=0.011), more robust females showed increased quantity and biomass of Branchiobdellidan
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