Eastern Bohemia Research Articles

Multi-proxy analysis of an Early Neolithic wooden well in a pastoral landscape in eastern Bohemia

Abstract Some of the most remarkable Neolithic finds encountered in central Europe are wells with a wooden construction. These features provide unusual insights into Neolithic societies, their subsistence strategies and the landscape they inhabited. In the last fifteen years, four Early Neolithic wells out of a total of seven such wells known since the 1970s have been discovered in Czechia. One of them is the well at Ostrov, the wooden construction and sedimentary infill of which have made it possible to study diverse topics by taking a multi-proxy approach using a range of complementary methods. The study presented here compares different periods of the well’s existence, examines the carpentry skills of the first farmers, investigates sedimentary processes, reveals details about the use and decline of the well, addresses its location relative to that of the settlement, and reconstructs the environment of the well itself and the surrounding landscape. The water well at Ostrov is a highly unusual find because it probably existed outside of a settlement. The grooved wooden lining used is identical to that of previously investigated wells inside settlements, as are the processes of its use and decline. However, environment-related indicates that the Ostrov well was located in an open landscape with sparse vegetation and was perhaps only used by-passing herdsmen.

Paleolitické bifaciální artefakty z východních Čech

Four Paleolithic lithic artefacts that were produced using the bifacial technique are currently known from the territory of Eastern Bohemia. Three of them, namely a knife from Bolehošt’ and leafpoints from Jaroslav and Černčice, were subjected to traceology analysis and 3D models of these artefacts were created. These models served as a basis for enhanced visualisation of their surface features using APSS surface analysis. Although in the case of the knife from Bolehošt’ and the point from Jaroslav no traces could be detected by tracer analysis, the point from Černčice can probably be interpreted as a knife on the basis of this method. One of the fractures on the artefact is also interesting, which seems to be the result of its re-shaping during the Paleolithic. The APSS analysis, in turn, has been proved to be a very promising tool for the documentation of lithic artefacts whose surface is also heavily weathered.

Nástin železniční dopravy ve východních Čechách

The following article outlines certain aspects of railway transport in Eastern Bohemia on the Pardubice – Česká Třebová line based on its own field sociological research from the personnel side. In their statements, two cultural consultants Jiří Rokos from the local line Cerekvice nad Loučnová and Miloslav Kolář from Moravany individually interpret their occupations in railway transport. They also present the development and individual layers of the history of this technique.

The Role of Cultural Life in a Small Town in Eastern Bohemia, and Its Potential Development of Cultural Tourism

The contribution of this paper is a discussion on the role of cultural life and the potential of cultural tourism in the small town of Choceň in Eastern Bohemia, which is not one of the first-class tourism localities in the Czech Republic. Despite this fact, there is a richness of natural and cultural attractiveness and the organization of varied cultural events. The goal of this research was to determine the assumptions of tourist attractiveness from the point of view of local actors, based on the hypothesis that the attractiveness of the city is closely linked to the attractiveness of tourism. Local actors are the ones who can recognize the genius loci of the place, which should have been considered in development planning. The literature review is mainly devoted to the role of culture, cultural tourism, and rural tourism. This research works with primary and secondary data, with the secondary data being based on location, selection, and implementation assumptions for tourism. The primary data were obtained using a quantitative questionnaire survey method for two target groups—local visitors and local entrepreneurs. This research shows that local actors are aware of their destination’s potential and support tourism development. However, cultural events are more likely intended to meet residents’ needs, not visitors. It is clear that small industrial towns are rather marginally devoted to the development of tourism. Yet, all local actors need to cooperate for further rural (and tourism) development.

Identifying silver-coated surfaces on Early Bronze Age axes from Bohemia

Deposits of bronze and copper artefacts are a common feature of the developed Únětice culture in Central Europe. Hoards of axes are especially frequent in Central Germany in the area between Halle, Salle and Dieskau. From this area come the most impressive assemblages of axe hoards. In Bohemia, Czech Republic, a more distant area from Central Germany, the hoards are less frequent and less rich. Until recently the largest hoards came from Northwest Bohemia, which was explained by its geographical closeness to Germany. However, this changed due to a find in Kukleny in Eastern Bohemia of 57 axes; it is the largest axe hoard in Bohemia so far. In total, 65 bronze axes were analysed in hoards found in Kukleny and Kunčice, a smaller hoard found only several kilometres from Kukleny. Our multimethod analysis, based on electron and reflected-light microscopy, identified surprising data related to the axes’ chemical composition, including strong evidence of silver and gold coatings, and we analysed the use-wear of the majority of the found axes.

Georg Bernard Verbeeck a jeho Vanitas ze šternberské sbírky na zámku v Častolovicích

The article deals with the cabinet picture Vanitas from the Sternberg collection, exhibited at the château in Častolovice in eastern Bohemia. This still life on copper plate was painted by Georg Bernard Verbeeck (†1673), a portraitist from the German town of Emmerich near the Dutch border. He moved to Prague with his nephew Jodokus Justus (1646–1700) and worked for the Lobkowitz family in Roudnice nad Labem and the Kolowrat family in Rychnov nad Kněžnou. The only painting attributed to Verbeeck that is not a portrait is an exploratory still life that has survived in relatively good condition. The work is signed and partially dated. The painting was in the possession of the Sternbergs at least from the time of Adolf Wratislaw of Sternberg (1627?–1703) and in the family asset inventories in Zásmuky and Častolovice it was designated Ein Todtenkopf The painting demonstrates exceptional realism and attention to detail. It combines many artistic symbols typical of the 17th century, expressing the themes of the finiteness of life and profligacy. This study, which is an addendum to our knowledge of the work of the almost unknown author of this painting, may help art historians in the future in the attribution of other paintings by Verbeeck, or more exactly, his circle.

K počátkům životní dráhy významného šlechtice husitské doby v českých zemích Haška z Valdštejna

The study provides the first detailed account of the early life of an important nobleman in the Czech lands, Hašek of Valdštejn. While his political career in the period after 1419 is relatively well known, the period prior to this date has not received due attention from historians. Hašek of Valdštejn was the most important member of the Valdštejn family until the time of the great Albrecht Václav Eusebius of Valdštejn in the 17th century. Like his famous relative nearly two hundred years later, Hašek had a major career in the military and diplomatic sphere in the 15th century. The author describes Hašek’s early life in the text. He came from the impoverished Dětenice branch of the family, which held domains in eastern Bohemia, as was first mentioned in written sources in 1404. It can be assumed that he was born sometime between 1385 and 1390. An important strategic decision was his departure from Bohemia to Moravia in 1410, where he managed to establish a prominent position for himself in the local aristocratic society. In Moravia, Hašek acquired the domain of Uherský Ostroh as a pledge by 1411 at the latest. Hašek also acquired the Víckov domain in Moravia at an unknown time. And while it is said that Hašek was the leader of the Budějovice-Hrotovice group of highwaymen in Moravia, the author emphasises that the existence of such a group of outlaws is not sufficiently documented in the sources. He concludes that this is an artificial construct of historians and that no such group existed.

Numbers and distribution of eagles in the Czech Republic: reason for optimism

At present, four eagle species are regular breeders in the Czech Republic: White-Tailed Sea-Eagle (Haliaeetus albicilla), Eastern Imperial Eagle (Aquila heliaca), Lesser Spotted Eagle (Aquila [Clanga] pomarina), and Golden Eagle (Aquila chrysaetos). There is also a historical record of confirmed breeding of Greater Spotted Eagle (Aquila [Clanga] clanga) in 1847 in the region of Eastern Bohemia. At present, this species is only a rare visitor on autumn and spring passage. White-Tailed Sea Eagle (Haliaeetus albicilla) has re-colonized the country since the mid-1980s, after approx. one hundred years absence as a breeder. The recolonization started at two separate areas: South Bohemia, with birds coming mainly from German and Poland source population, and South Moravia, with birds coming from Pannonia, i.e. mainly from Hungary. Later the species occupied nearly the whole area of suitable habitats. The population is still increasing and currently reaches ca. 160–180 breeding pairs. Eastern Imperial Eagle (Aquila heliaca) has bred in the Check Republic for the first time in 1998 (there is one unconfirmed note about its breeding also in 1930s). Since then, the population is slowly growing, similarly as the whole Pannonian population (with source populations mainly in Hungary and Eastern Slovakia). So far, the breeding is limited to Pannonian region of the country (i.e. south-eastern part) but the first pairs have spread north and west during the last years. 23 territorial pairs were monitored in 2023. The Lesser Spotted Eagle (LSE, Aquila [Clanga] pomarina) was never an abundant species in the Czech Republic. Scarce population existed especially in submountainous regions and in the mountains throughout the CR. The last breeding pairs were documented at the end of 1980’s and the beginning of 1990’s in Šumava Mts. After more than 20 years, breeding of LSE was surprisingly confirmed in western Bohemia. Since 2012, one pair breeds there regularly. In 2018, a small new population was discovered in the north of Morava region and currently three pairs breed there. Since 2020, another pair breeds in eastern Bohemia. Presently, two pairs breed in this region but we presume that another 1–2 breeding pairs could be hiding in this region. Therefore, in 2023 we estimate the breeding population of the LSE in the Czech Republic as 6–8 pairs. Golden Eagle (Aquila chrysaetos) started to breed in Northern Moravia (NE part of the country) in 2013 (similarly as White-Tailed Sea Eagle after more than one hundred years of absence), partly as a result of re-introduction project carried out during 2006–2017 (27 birds originating from Slovakia were released). Along with the growing population size and range expansion in the neighbouring Slovakia, there are now min 5–6 occupied territories in Czech Republic. Osprey (Pandion haliaetus) is a regular passage migrant (both spring and autumn), with some birds oversummering and very rarely also wintering. Historical data about its regular breeding in 19th or even early 20th century are not fully confirmed. Several breeding attempts were recorded also during the last 20 years. These included nest building but the clutch was never laid. Short-Toed Snake Eagle (Circaetus gallicus) is a very rare visitor in the Czech Republic, but the number of observations seems to increase rapidly during the last 10 years. With the increasing population in Hungary and possibly also Slovakia, its breeding cannot be excluded in the near future.

Smoothie Drinks: Possible Source of Resistant and Biofilm-Forming Microorganisms.

Smoothie drinks are currently very popular drinks sold especially in fast food establishments. However, smoothies are a significant source of microorganisms. The aim of this study was to evaluate the microbiological quality of smoothies purchased in Eastern Bohemia. A higher prevalence of mesophilic aerobic bacteria (5.4-7.2 log CFU/mL), yeast (4.4-5.9 log CFU/mL) and coliform bacteria (3.1-6.0 log CFU/mL) was observed in vegetable smoothies, in which even the occurrence of enterococci (1.6-3.3 log CFU/mL) was observed. However, the occurrence of S. aureus, Salmonella spp. and Listeria spp. was not observed in any samples. Nevertheless, antimicrobial resistance was observed in 71.8% of the isolated strains. The highest level of resistance was found in isolates from smoothie drinks with predominantly vegetable contents (green smoothie drinks). Considerable resistance was observed in Gram-negative rods, especially to amoxicillin (82.2%) and amoxicillin with clavulanic acid (55.6%). Among enterococci, only one vancomycin-resistant strain was detected. The vast majority of isolated strains were able to form biofilms at a significant level, which increases the clinical importance of these microorganisms. The highest biofilm production was found in Pseudomonas aeruginosa, Kocuria kristinae and Klebsiella pneumoniae. Overall, significant biofilm production was also noted among isolates of Candida spp.

Situovaná (auto)mobilita ve venkovském mikroregionu

The paper examines the assumptions and conditions of (auto)mobility in a rural microregion in eastern Bohemia, specifically in the localities of municipalities of Široký Důl and Trstěnice. In this manner situated mobility becomes an important part of the research. Using this background, the relationships of transport users to mobility, their experiences, ideas and opinions are studied. Knowledge included in the study was obtained through the author’s own field research. The overall picture of historical development of motoring would not be complete without rural environment forming specific conditions for this area of practical human activity.

Křídové pískovce u Ždírce nad Doubravou (Českomoravská vrchovina): materiál pro gotické sakrální stavby v širokém okolí

The narrow, 40 km long belt of the Cretaceous sediments called „The Dlouhá mez“ has been preserved along the NW-SE-striking Železné hory fault within crystalline rocks in the Eastern Bohemia (Fig. 1). The youngest relic of this belt corresponds to the middle part of Jizera Fm. of middle Turonian age. In the southeastern part of the „Dlouhá mez“ belt, these deposits have fine-grained, glauconitic sandstone nature. Near the town of Ždírec nad Doubravou, the sandstone had been exploited for a long time in several presently abandoned quarries and used as a building material. The old quarry at the margin of Ždírec nad Doubravou was founded in the end of the 13th century, and it was replaced by new quarries between Ždírec nad Doubravou and the village of Nový Studenec in the second half of the 19th century. This sandstone was discovered in four gothic buildings in the wide surroundings of these quarries within the course of the macroscopic investigation by the author. To confirm this discovery, the author carried out microscopic investigation of ten sandstone samples taken both in the quarries and in the gothic buildings. Petrographic features of the sandstone were also specified. Microscopic study confirmed the identical character of all studied samples. The identity of sandstone exploited in the quarries and sandstones used in gothic buildings was also demonstrated by the analysis of total SiO2 content. The sandstone is fine-grained, with matrix-supported texture, variable content of glauconite grains and fragments of silicisponge spicules and rare foraminifera tests. Muscovite and feldspars occur in accessory amounts. The sandstone is silicified and exhibits a porosity from 6–8 to 20 %. The pores with very elongated, needle-like form originated by diagenetic dissolution of silicisponge spicules while the diagenetic quartz penetrated the original clayey and possibly also calcareous matrix. The foraminifera tests were also silicified during this process. Within subordinate thin layers in sandstone, the content of terrigenous quartz grains drops below 25 % (20–22 %) while the content of silicisponges fragments increases to 10–12 %. These layers can be classified as spiculitic, sandy silicite. The sandstone from Ždírec nad Doubravou was documented in two village churches (Krucemburk, Havlíčkova Borová), in a big church in the town of Havlíčkův Brod and in the chapel in the Lipnice Castle in the town of Lipnice nad Sázavou. These buildings originated in the last quarter of the 13th and in the 14th century. These localities are from 4 to 32 km away from the quarries near the town of Ždírec nad Doubravou (Fig. 1). The sandstones were used as ashlar masonry, window jambs and tracery, vault ribs and also in sculptures (figural corbels). A further investigation can probably reveal the Ždírec nad Doubravou sandstone in a higher number of medieval buildings.

Audioprůvodce – běžná součást, nebo nadstavba expozice?

The article deals with the possibilities of using audio guides in current museum exhibitions. It represents their potential, risks of implementation and also the limits that they may represent for visitors during a routine inspection of memory institutions. At the same time, through the author‘s own experience with the preparation of the audio tour for the exhibition City roads of the Museum of Eastern Bohemia in Hradec Králové, provides the reader with a critical evaluation of the positives and negatives resulting from the preparation of the entire route.

Podrobnosti o počátcích sedimantace a vulkanické činnosti na začátku permu (asselu); rudnický obzor v sz. části podkrkonošské pánve

A succession of the early Permian (Asselian) Rudník member exposed at the locality Škodějov – Hrádecký potok in the northwestern part of the Krkonoše Piedmont Basin (eastern Bohemia) contains light-colored clastic rocks with macroscopically conspicuous lamination, overlying lacustrine bituminous claystones and siltstones (ʻblack shalesʻ). This work aims to constrain the origin of those laminated strata. They can be macroscopically described as heterolithic sequence formed by fine- to medium-, exceptionally coarse-grained sandstone with intraclasts of mudstone, calcified fine-grained sandstone, mudstone and claystone with interlayers of organic-rich laminae. Volcaniclastic rocks are also present. The heterolithic volcanosedimentary sequence comprises cyclic (up to 4 dm), mostly horizontally laminated rocks, in places with soft- sediment deformation structures. Diagenetic phenomena, related to calcification of volcaniclastic layers and growth of pyrite crystals and framboids, are common. Volcaniclastic rocks with a predominance of albitized volcanic glass fragments are interpreted as vitritic tuffs. Fragments of volcanic glass floating in silty to fine-grained sandy matrix contain vesicules and are locally brown- colored. They are reinterpreted as being derived from contemporary intermediate (andesitic) volcanism, most likely extrabasinal. Extensive alteration of volcanic material makes characterization of the original composition of volcaniclastic deposits difficult. Trace element analysis using a portable XRF spectrometer revelaed negligible concentrations of V, Ni and Ti, which are indicative of rather basic volcanism. Results of outcrop-scale gammaspectrometry are presented here as trends of Th/U ratio of relevant lithotypes from several localities of the Rudník member. Organic-rich laminae present within the heterolithic succession at Hrádecký potok section are commonly rich in pyrite clusters. Those are the most probably related to formation of algal mats stimulated by input of fine-grained volcaniclastic material into the Rudník Lake. However, elevated siliciclastic and volcaniclastic input, particularly during periods of intensified volcanic activity, with related seismic events (that may have triggered gravity flows), may have disturbed or punctuated growth of algae on the lake floor. Our work has shown that the volcanic activity at the onset of deposition of the Rudník member in the northwestern part of Krkonoše Piedmont Basin (Škodějov – Hrádecký potok) was probably of intermediate nature and that it influenced depositional environment. Particularly, the fluctuating input of clastic and volcanogenic material could have caused an alternation of oxic and dysoxic conditions in the lake lacustrine environment over time. The intermediate character of volcanism in this locality contrasts with confirmed acidic volcanism documented in volcaniclastic layers in another lacustrine succession at Vrchlabí – roadcut (Martínek et al. 2006) that probably represent a different eruptive phase recorded within the Rudník member.

Finding an imprint of solar and climatic cycles in tree rings of European beech (Fagus sylvatica L.)

The present study is focused on European beech (Fagus sylvatica L.) growth in eastern Bohemia in the Broumovské stěny National Nature Reserve, Czech Republic. The objective of this research was to develop an evaluation of European beech radial growth in relation to solar activity (number of sunspots), air temperature in the growing season, annual precipitation and air pollution (SO<sub>2</sub> depositions). The highest positive significant correlation coefficient was found between radial growth of European beech and number of sunspots, followed by the correlation with air temperature in the growing season. The radial growth showed a negative significant correlation with SO<sub>2</sub> depositions. The correlation of the radial growth indicates that precipitation and sunspots have a lower correlation coefficient with beech growth than seasonal temperature during an air pollution disaster in the 21st solar cycle. Radial growth, precipitation total and air temperature in the growing season were processed by spectral analysis for the evaluation of periodic cycles. The 7.5- to 11-year cycles were observed in air temperature and in sunspot cycles. Precipitation and air temperature in the growing season indicate a higher frequency at 3.7-year cycles. The long-term periodicity of radial growth was influenced by both solar activity and fluctuations of growing-season air temperature.

Differences in Potamogeton praelongus Morphology and Habitats in Europe

AbstractOne of the most southern European occurrences ofPotamogeton praelongusis in the Czech Republic (CR), with only one native population in the Orlice River floodplain in Eastern Bohemia, the only surviving site from 10 Czech localities known 45 years ago. This species is critically endangered in the CR and needs to be actively protected with a rescue program. The number ofP. praelongussites increases along a latitudinal gradient, from Central to North Europe (CR, Poland, Sweden, and Norway), and correlates with improving conditions (water transparency and nutrient content in water) for this species along this gradient. Although differences in site conditions between Central and North Europe were caused by changes in landscape geomorphology and vegetation during the glacial and postglacial eras, presently, anthropogenic impact is primarily observed.The Czech sites forP. praelongushave distinctly lower water depth and transparency, and conversely, higher conductivity, temperature, and shade levels than the Nordic ones. These extreme conditions in most biotopes of this light-demanding and mesotrophic species in the CR result in lower fitness and different morphological parameters in the Czech populations. These changes lead to decreased competitive ability against filamentous algae and more competitive aquatic plant species and increase the impact of animals.The Nordic nonintensively managed landscape provides numerous large, deep lakes, which are optimal for this aquatic species. In the CR,P. praelonguscan currently only survive in rivers and their oxbows, but these are heavily influenced by intensive landscape management and fishing. Comparison of the populations and their site conditions in the CR and other European countries showed that all Czech native and artificially established sites are exposed to eutrophication and its consequences, which are the most important factors affecting the survival ofP. praelongus.

Two trajectories of the development of pottery forming methods in central Europe in the Iron Age: The contribution of analysis of the orientation of components of a ceramic body

In this article, the development of pottery-forming techniques employing rotational movement during the La Tène period in two different regions of central Europe is compared. One region represents a small, rather peripheral, region in Eastern Bohemia (Czech Republic). Results of the technological analysis in this region have already been published. The other region is a newly-analysed region situated in South Moravia (Czech Republic) with evidence of intensive use of the local landscape throughout the La Tène period. The comparison is based on a quantitative analytic technique measuring the orientation of a ceramic body’s components. Results of the analysis indicate different conditions for the transmission of the technology. In one case, there is evidence for disruptive changes in the technology, while in the other case, continuous development with an increasing proportion of wheel-thrown pottery is observed.

Vodní měkkýši přírodní rezervace Maštale (východní Čechy) [Aquatic molluscs of the Maštale Nature Reserve (East Bohemia)

The Maštale Nature Reserve (Eastern Bohemia, Czech Republic) represents a system of rocky sandstone valleys with springs, ponds and several streams. Aquatic molluscs of this area have never been studied, which became a reason for the first inventory conducted in 2019 and 2020. Altogether 19 species were found at 39 sites, from which Radix labiata, Gyraulus albus, Ancylus fluviatilis and Pisidium casertanum belonged among the most often recorded species while Bythinella austriaca, Acroloxus lacustre, Lymnaea stagnalis, Anodonta anatina, Pisidium milium and P. personatum were found at only one or two sites. Majority of recorded molluscs belonged to common and widespread species; only gastropod Bythinella austriaca and pea mussels Pisidium milium and P. obtusale are listed in the Red List of the Czech Republic in the category Near Threatened. The occurrence of hydrobiid B. austriaca in the area where sandstone dominated is noteworthy. Two non-native species Physa acuta and Ferrissia californica were found.

Hidden below‐ground plant diversity buffers against species loss during land‐use change in species‐rich grasslands

AbstractQuestionsTheory suggests that while plant diversity of grasslands decreases in response to increased competition for light, many plant species persist below‐ground even in the temporary absence of shoots. Thus, we hypothesized that below‐ground, diversity is less affected by increased competition during land‐use change compared to above‐ground.LocationSpecies‐rich, oligotrophic grasslands in the Železné hory Mts, eastern Bohemia, Czech Republic.MethodsWe quantified above‐ and below‐ground plant richness (roots and rhizomes, seed and bud bank) in grasslands subjected to seven years of experimental abandonment and fertilization. We used conventional species identification to measure richness above‐ground and 454 sequencing of the chloroplast trnL (UAA) gene to measure richness of roots and rhizomes; additionally, we used the shoot emergence method to measure soil seed and bud bank richness.ResultsWhile above‐ground richness decreased with abandonment and fertilization, below‐ground richness remained less affected or even increased compared to the control (traditional mowing). Overall, compared to above‐ground the proportion of plant species found only below‐ground as roots and rhizomes increased, particularly in the abandonment with fertilization treatment.ConclusionsBelow‐ground plant diversity could potentially buffer against biodiversity losses during short‐term land‐use change. Our findings highlight that measuring the complete plant species diversity improves our understanding of processes that underlie plant diversity and coexistence and refine predictions of vegetation responses to biodiversity threats.

Epigravettian in Eastern Bohemia

Until recently the Epigravettian occupation of Bohemia has remained relatively unknown. After re-evaluating an old assemblage from Ostroměř (first published by S. Vencl like the Ostroměř group of Late Palaeolithic) we can assign it to the Epigravettian cultural complex. A newly excavated site in Slatinky near Jičín probably dates to the Late Epigravettian, but only the specialised part of the site related to the production of microblades was excavated. Eastern Bohemian sites fit into the general form and framework of the Epigravettian stone industries with a dominance of short scrapers (often on flake) and a lower incidence of burins. Geographically, sites can be placed mainly in lower altitudes (256–400 m asl), while their number decreases with increasing altitude. There is no link to large watercourses, and on the contrary, the main ones seem to be rather smaller watercourses (sites are located 100–300 m from them) while at the same time it is clear that there was an effort made to search for places protected against adverse climatic phenomena. At the moment we can first provide a deeper insight into the Epigravettian site structure in Eastern Bohemia.

Vodní měkkýši Sázavy a vybraných přítoků se zaměřením na ohrožené a nepůvodní druhy [Aquatic molluscs of the Sázava River and its selected tributaries with a focus on threatened and non-native species

This paper presents the results of a malacological survey of the Sázava River and its tributaries conducted over the last 20 years. The Sázava River (Czech Republic, Central and Eastern Bohemia) is one of the major tributaries of the Vltava River. Altogether 45 species of aquatic molluscs were found at 221 sites located at the Sázava River and its tributaries. More than 60% of recorded species of the Sázava River and its tributaries are common and widespread. The population of critically endangered Margaritifera margaritifera in the Jankovský potok is near extinction. Other threatened bivalves Pseudanodonta complanata, Unio crassus and Sphaerium rivicola were recorded in the Sázava River. Populations of U. crassus were also found in several tributaries (Blanice, Hejlovka, Martinický potok) while in the Sázavka Brook and the Želivka River only a few individuals were found. Gyraulus acronicus, a rare gastropod in the Czech Republic, was recorded in the Blanice River and several dam reservoirs. Four non-native species (Potamopyrgus antipodarum, Physa acuta, Gyraulus parvus, Dreissena polymorpha) were found in the monitored streams and reservoirs but usually in a relatively small number of localities. Most of these were located in the lower section of the Sázava River, Švihov dam reservoir and some tributaries.