Eastern Czech Republic Research Articles

First Report of Polymyxa graminis f. sp. temperata, a Vector of Soilborne Cereal Viruses in the Czech Republic.

Polymyxa graminis L. is an eukaryotic, obligate, biotrophic parasite of plant roots (1), which belongs to a poorly studied, discrete, taxonomic unit informally called the 'plasmodiophorids'. P. graminis has the ability to acquire and transmit a range of soilborne viruses that belong to at least three separate genera and can cause economically significant diseases in cereal crops. For example, the winter barley disease caused by Barley yellow mosaic virus (BaYMV) and/or Barley mild mosaic virus (BaMMV) is widespread in Europe, Japan, and China; yield losses of >50% may occur when susceptible barley cultivars are grown on severely infested soils (2). Monitoring for P. graminis was started in the Czech Republic in May 2008. Fifty-six soil samples were collected from different localities of cereal production (wheat and barley) in the Královéhradecký Region (eastern Czech Republic). Soil from each sample was placed in five replicate pots (12 × 12 cm) in a greenhouse at 22 to 25°C. Seeds of barley cv. Florian were sown into the soil (10 seeds per pot). Negative control soil (noninfested soils from the Czech Republic) and positive control soil (known P. graminis-infested soil from Germany) were also planted to barley in five replicate pots. After 90 days, plants were collected and the roots were washed thoroughly in sterilized water and examined with a light microscope without staining. The fungus was identified as P. graminis on the basis of morphology of resting spores (cystosori) and sporangia and the size of individual cystosori (4 to 5 μm in diameter) according to Thouvenel et al. (3). Cystosori of P. graminis were observed in the roots of plants grown in 20 of the 56 soil samples, especially the samples from Ceské Mezirici. The presence of P. graminis in the roots of plants grown in the soil samples and the positive control sample versus the absence of the vector in roots of plants in the negative control soil was verified by PCR assay with DNA extracts and the Psp1 and Psp2rev primers according to Legrève et al. (Page 40 in: Proceedings of the Fifth Symposium of the International Working Group on Plant Viruses with Fungal Vectors, 2003). The PCR assay included denaturation at 94°C for 2 min, then 35 cycles including denaturation of 30 s at 94°C, annealing at 60°C for 1 min, and elongation at 72°C for 35 s. A final elongation was completed at 72°C for 7 min. To characterize the P. graminis isolates, the amplified PCR product (a DNA fragment of 472 bp) was sequenced and blasted for each of the samples that tested positive. These sequences were aligned with a known sequence (GenBank Accession No. AM259276) for P. graminis. The sequences from P. graminis on barley were 100% homologous to the published sequence of P. graminis f. sp. temperata. To our knowledge, this is the first report of P. graminis f. sp. temperata in the Czech Republic.

Estimating forest variables from top-of-atmosphere radiance satellite measurements using coupled radiative transfer models

Traditionally, it is necessary to pre-process remote sensing data to obtain top of canopy (TOC) reflectances before applying physically-based model inversion techniques to estimate forest variables. Corrections for atmospheric, adjacency, topography, and surface directional effects are applied sequentially and independently, accumulating errors into the TOC reflectance data, which are then further used in the inversion process. This paper presents a proof of concept for demonstrating the direct use of measured top-of-atmosphere (TOA) radiance data to estimate forest biophysical and biochemical variables, by using a coupled canopy–atmosphere radiative transfer model. Advantages of this approach are that no atmospheric correction is needed and that atmospheric, adjacency, topography, and surface directional effects can be directly and more accurately included in the forward modelling. In the case study, we applied both TOC and TOA approaches to three Norway spruce stands in Eastern Czech Republic. We used the SLC soil–leaf–canopy model and the MODTRAN4 atmosphere model. For the TOA approach, the physical coupling between canopy and atmosphere was performed using a generic method based on the 4-stream radiative transfer theory which enables full use of the directional reflectance components provided by SLC. The method uses three runs of the atmosphere model for Lambertian surfaces, and thus avoids running the atmosphere model for each new simulation. We used local sensitivity analysis and singular value decomposition to determine which variables could be estimated, namely: canopy cover, fraction of bark, needle chlorophyll, and dry matter content. TOC and TOA approaches resulted in different sets of estimates, but had comparable performance. The TOC approach, however, was at its best potential because of the flatness and homogeneity of the area. On the contrary, the capacities of the TOA approach would be better exploited in heterogeneous rugged areas. We conclude that, having similar performance, the TOA approach should be preferred in situations where minimizing the pre-processing is important, such as in data assimilation and multi-sensor studies.

Pathogens of the spruce bark beetles Ips typographus and Ips duplicatus

Abstract Pathogens of two important bark beetles, Ips typographus and Ips duplicatus, both in outbreaks connected with infestation of spruces by the fungus Armillaria ostoyae, were compared at four localities in the eastern Czech Republic. Low infestations of Chytridiopsis typographi, Nosema typographi, Menzbieria chalcographi, and Gregarina typographi were detected in I. typographus. In I. duplicatus, only C. typographi and G. typographi were found and with low infection levels. The microsporidium, Larssoniella duplicati, was not detected in I. typographus, but was detected in I. duplicatus at all localities in almost 80% of the samples (a sample consisted of 40–50 beetles collected at one locality in one period) and often with a very high infection level (up to 57% of the beetles infected in a sample). The infection level of L. duplicati did not differ between generations of I. duplicatus. I. duplicatus overwinters mainly in the adult stage, and no decrease in the number of infected overwintering I. duplicatus was observed. The relatively constant infection level of L. duplicati suggests that transmission is unlikely to be horizontal via oral ingestion.

Morava River floodplain development during the last millennium, Strážnické Pomoraví, Czech Republic

Floodplain sediments deposited along the lower course of the Morava River (eastern Czech Republic), were studied in the Strážnické Pomoraví region to describe the alluvial history of the river over the last millennium. The sediments exposed in up to 5 m high erosional river banks were analysed using mineral magnetic, geochemical and chemical approaches. The age model of the sedimentary sequences was constructed from radiocarbon dates in association with 206Pb/207Pb and POP (DDT, PCB) analysis and 137Cs activity data. The Cu-trien method was used for stratigraphically correlating these deposits based on the variation of expandable clay minerals in the sediments. The resulting stratigraphic pattern reveals the alluvial history of the currently active river channel system since the end of the first millennium AD. Fine overbank clayey sediments deposited during the `Mediaeval Warm Period' were eroded from cultivated fields newly formed during Mediaeval colonization between 1250 and 1450. These fine deposits are overlain by coarser floodplain sediments of the `Little Ice Age', indicating a change in the sediment source since the sixteenth century AD, and a substantial increase in the sediment load in the second half of twentieth century. The Strážnické Pomoraví floodplain deposits represent a valuable palaeoenvironmental archive of the last millennium, containing records of fluvial processes considerably altered by human activities.

Effects of different cultivation types on native and alien weed species richness and diversity in Moravia (Czech Republic)

Changes in weed species richness and beta-diversity are partly attributable to different types and intensity of disturbance and partly to broad-scale variation in environmental conditions. We compiled a data set of 434 vegetation plots of weed vegetation in root crop and cereal fields in Moravia (eastern Czech Republic) to compare the effects of environmental conditions and different disturbance regimes on species richness and beta-diversity. To detect changes in species richness, we related the variation in species richness to individual environmental conditions. To assess differences in beta-diversity between the vegetation of cereal and root crop fields, we used Whittaker's measure of beta-diversity. The relative importance of each environmental variable for the variation in species composition was evaluated using canonical correspondence analysis. All analyses were done for all vascular plant species and separately for native species, archaeophytes and neophytes. A comparison of weed vegetation of root crops and cereals showed a distinct dichotomy between these two types of weed vegetation. There was no significant difference in total species richness and native species richness; however, cereal fields were richer in archaeophytes and root crop fields were richer in neophytes. The beta-diversity of weed vegetation was higher in root crops. Environmental factors explained a significant part of the variability in richness of both natives and aliens. The richness of native species increased and beta-diversity decreased with increasing precipitation. The opposite relationship was found for archaeophytes, in both cereals and root crops. These results confirmed the importance of climatic factors and management practices for changes in weed species composition. They also showed a distinct pattern of species richness and beta-diversity of native and alien weed species. Veränderungen im Artenreichtum der Kräuter und in der Beta-Diversität können teilweise auf unterschiedliche Typen und Intensitäten von Störungen und teilweise auf umfassende Veränderungen in den Umweltbedingungen zurückgeführt werden. Wir stellten einen Datensatz von 434 Flächen krautiger Vegetation in Rüben- und Getreidefeldern in Moravia (Ost-Tschechien) zusammen, um die Auswirkungen der Umweltbedingungen und der unterschiedlichen Störungsregime auf den Artenreichtum und die Beta-Diversität zu vergleichen. Um die Veränderungen im Artenreichtum festzustellen, stellten wir eine Beziehung zwischen der Variation des Artenreichtums und den individuellen Umweltbedingungen her. Um die Unterschiede in der Beta-Diversität zwischen den Getreide- und Rübenfeldern abzuschätzen, benutzten wir Whittakers Maß für die Beta-Diversität. Die relative Bedeutung eines jeden Umweltfaktors für die Variation in der Artenzusammensetzung wurde mit kanonischen Korrespondenz-Analysen bewertet. Alle Analysen wurden für alle Gefäßpflanzenarten und getrennt für einheimischen Arten, Archeophyten und Neophyten durchgeführt. Der Vergleich zwischen der Krautvegetation in Rüben- und Getreidefeldern zeigte eine eindeutige Dichotomie zwischen diesen zwei Typen der Krautvegetation. Es gab keinen signifikanten Unterschied im Gesamtartenreichtum und dem Artenreichtum einheimischer Pflanzen, Getreidefelder waren jedoch artenreicher in Bezug auf Archaeophyten und Rübenfelder in Bezug auf Neophyten. Die Beta-Diversität der Krautvegetation war in den Rübenfelder größer. Die Umweltfaktoren erklärten einen signifikanten Anteil der Variation im Artenreichtum bei einheimischen und fremden Arten. Mit zunehmenden Niederschlag nahm der Artenreichtum der einheimischen Arten zu und die Beta-Diversität ab. Die gegenteilige Beziehung wurde für die Archaeophyten sowohl in Getreide- als auch Rübenfeldern gefunden. Diese Ergebnisse bestätigen die Bedeutung der klimatischen Faktoren und der Bewirtschaftungspraxis für die Veränderungen in der Zusammensetzung der krautigen Arten. Sie zeigen außerdem ein bestimmtes Muster des Artenreichtums und der Beta-Diversität für einheimische und fremde krautige Arten.

Late Holocene catastrophic slope collapse affected by deep-seated gravitational deformation in flysch: Ropice Mountain, Czech Republic

The region of the Flysch Western Carpathians is characterized by abundant deep-seated gravitational slope deformations (DSGSDs). This study deals with a detailed analysis of Late Holocene catastrophic collapse of a fault-created slope of Mountain Ropice in the Moravskoslezské Beskydy Mountains (eastern Czech Republic). The catastrophic collapse was initialized by huge compound rotational slide/toppling deformation which occurs on the upper part of the studied slope and affects tectonically weakened, subhorizontally inclined sandstone beds. Detailed geomorphological mapping accompanied by morphotectonic analysis and geophysical sounding revealed at least two historic flowslides. The older event (F1) affected 0.5–0.8 Mm 3 of bedrock and created a 1000-m-long and up to 150-m-wide accumulation with abundant transverse steps and a carapace-like surface. The landslide toe blocked an adjacent valley, which led to the development of a small impoundment with ∼ 4-m-thick deposits containing lacustrine-peat bog, floodplain and alluvial fan facies. Radiocarbon dating and pollen analysis indicate the valley blockage at ∼ 1.5 ka BP. The other flowslide (F2) of much smaller dimensions (10 000–12 000 m 3) overlaid the main landslide body and, according to the dating of minerogenic horizon in the impoundment, may have taken place < 0.3 ka BP. The organisation of landforms, character of slope failures and dynamic back-modelling point to a likely rock avalanche (or combined rock slide–debris avalanche) mechanism of movement. This case study shows that rapid rock avalanches can operate also in mountainous terrain with moderate relief if toppling together with deep-seated gravitational deformation of slopes modifies the original stable position of bedding planes.

Climate‐ and resource‐driven long‐term changes in dormice populations negatively affect hole‐nesting songbirds

AbstractGlobal climate change has been shown to cause variable shifts in phenology in a variety of animals and unexpected outcomes across food chains are to be found. Here we examined how rising annual spring temperatures affected the interactions between seed masting, cavity nesting birds and dormice using long‐term data from Eastern Czech Republic. We have shown that climate change was associated with unequal shifts in the phenology of two cavity‐breeding groups: dormice and birds. Rising spring temperatures have progressively advanced the termination of hibernation for the edible dormouse Glis glis, a common bird predator, leading to an increasing overlap in the use of nesting boxes between dormice and birds. In contrast, only the collared flycatcher Ficedula albicollis, of the four cavity‐nesting bird species, advanced its breeding dates in response to rising temperatures. At the same time, favourable weather conditions, coupled with good seed masting years, have been associated with a substantial rise in dormice numbers. Concurrent with the increasing dormice abundance, the number of bird nests destroyed significantly increased in three out of four bird species. We showed that while there was a significant change in the date that the dormice emerged from hibernation during the course of the study, it did not significantly contribute to predation levels when controlling for their abundance and timing of breeding in birds. We found that the increasing dormice abundance was the main factor causing high brood losses in birds, while the timing of breeding in birds had a variable effect between bird species. This study illustrates how changes in climate might affect organisms at various trophic levels with often unexpected outcomes. Limited evidence from other study organisms suggests that species most at risk are those at different trophic levels that do not shift at the same rate or in the same direction as their food resources, predators or competitors.

Correlation Between Magnetic Susceptibility and Heavy Metal Concentrations in Forest Soils of the Eastern Czech Republic

Magnetic susceptibility measurements were performed on 2,000 samples of forest soils from the Ostrava-Karvina industrial region (Czech part of Upper Silesian Coal Basin) and the Moravian-Silesian Beskydy Mountains and their piedmont area, Podbeskydi. Concentrations of selected elements were determined in 1,200 samples from the same set. Industrial facilities (metallurgical industry and power plants) located in this region represent major sources of both magnetic particles and risk elements contaminating soils within the industrial region and neighboring mountainous areas. The magnetic susceptibility has a closely correlated relationship with Zn, Fe, As, Pb and Cu concentrations in soils. The magnetic susceptibilities vary inversely with distance from the sources. The behavior of individual chemical elements during transport and deposition was studied by means of ratios of concentrations of elements and values of magnetic susceptibility. Metals correlating very closely with magnetic susceptibility (Fe and Zn) were deposited together with dust particles, whereas Pb, As, and trace amounts of Zn can create independent particles which are components of long distance transport and deposition. The concentrations of Pb, As and, in part, Zn in soils are strongly dependent on the elevation of the sampling site; in the uppermost parts of mountains they are enriched. Other studied elements show neither relationship with sources of air pollution, nor with the geomorphology of the area. Concentrations of chemical elements V, Cr, Rb, Sr, U, Zr, Ca, Bi, Mn and Ti are related mostly to underlying sedimentary rocks.

Correlation between flight activity of sawflies Pristiphora abietina, P. saxesenii, P. gerula and P. leucopodia (Hymenoptera: Tenthredinidae) and spruce (Picea abies) bud breaking in Eastern Czech Republic

The flight activity of spruce tenthredinids were studied using Malaise traps and yellow sticky boards in young spruce forests in the Nízký Jeseník Hills during years 2005 and 2006. In most cases, studied species (&lt;I&gt;Pristiphora abietina, Pristiphora saxesenii, Pristiphora gerula, Pristiphora leucopodia&lt;/I&gt;) showed a statistically significant correlation between numbers of specimens caught at two- or three-day periods and numbers of budded spruces in both years.

Progressive drowning of carbonate platform in the Moravo-Silesian Basin (Czech Republic) before the Frasnian/Famennian event: facies, compositional variations and gamma-ray spectrometry

The Moravo-Silesian Basin (MSB; eastern Czech Republic and southern Poland) hosted an extensive shallow-water carbonate platform in the Middle Devonian to Frasnian interval. The platform drowned in a stepwise fashion from the Palmatolepis hassi to the Pa. linguiformis zone. Three types of drowning successions were revealed from conodont biostratigraphy, facies, microfacies and gamma-ray spectrometry data: (A) drowning to periplatform turbidite setting; (B) drowning to (hemi)pelagic seamount setting and (C) drowning associated with the stratigraphical gap. In the lower Pa. hassi zone, rapid subsidence caused the platform to drown locally along the N–S to NW–SE trending faults (type A drowning). In the upper Pa. rhenana to the Pa. linguiformis zone, the drowning accelerated in the western part of the MSB due to locally higher subsidence rates combined with the Late Frasnian biotic crisis (type B). In the southern part of the basin, the platform emerged shortly before the Frasnian/Famennian (F/F) boundary and drowned in the Early to Late Famennian (type C). The primary cause of drowning was differential subsidence at the Laurussian passive margin. Eustatic sea-level fluctuations, if any, contributed only to a minor extent to the Late Frasnian drowning, but were effective in type C drowning during the Famennian. The drowning boundaries are associated with increased contents of K and Th, reflecting the deceleration of carbonate production. Uranium contents display isolated peaks that roughly correlate with the drowning boundaries or the stratigraphic gaps associated with the F/F boundary. The uranium contents are considered to reflect local depositional conditions and are not suitable for stratigraphic correlation. On the other hand, from the K and Th contents, we can infer Late Frasnian sea-level fluctuations with duration on the order of 1 Myr. These cyclic variations in K and Th contents proved to be useful in platform-to-basin stratigraphic correlation.

Vertical extrusion and middle crustal spreading of omphacite granulite: a model of syn‐convergent exhumation (Bohemian Massif, Czech Republic)

AbstractThe exhumation of eclogite facies granulites (Omp–Plg–Grt–Qtz–Rt) in the Rychleby Mts, eastern Czech Republic, was a localised process initiated by buckling of crustal layers in a thickened orogenic root. Folding and post‐buckle flattening was followed by the main stage of exhumation that is characterized by vertical ductile extrusion. This process is documented by structural data, and the vertical ascent of rocks from a depth of c. 70 to c. 35 km is documented by metamorphic petrology. SHRIMP 206Pb/238U and 207Pb/206Pb evaporation zircon ages of 342 ± 5 and 341.4 ± 0.7 Ma date peak metamorphic conditions. The next stage of exhumation was associated with sideways flat thrusting associated with lateral viscous spreading of granulites and surrounding rocks over indenting adjacent continental crust at a depth of c. 35–30 km. This stage was associated with syntectonic intrusion of a granodiorite sill at 345–339 Ma, emplaced at a crustal depth of c. 25 km. The time required for cooling of the sill as well as for heating of the country rocks brackets this event to a maximum of 250 000 years. Therefore, similar ages of crystallization for the granodiorite magma and the peak of eclogite facies metamorphism of the granulite suggest a very short period of exhumation, limited by the analytical errors of the dating methods. Our calculations suggest that the initial exhumation rate during vertical extrusion was 3–15 mm yr−1, followed by an exhumation rate of 24–40 mm yr−1 during further uplift along a magma‐lubricated shear zone. The extrusion stage of exhumation was associated with a high cooling rate, which decreased during the stage of lateral spreading.

Slope movements in the Flysch Carpathians of Eastern Czech Republic triggered by extreme rainfalls in 1997: a case study

The severe rainfalls in Northern and Central Moravia and Eastern Bohemia in July 1997, triggered slope movements recorded particularly in the flysch-type rocks of Northern and Eastern Czech Republic. The basis of the diversified woodland and agricultural landscape of the Western Carpathians is the highland and mountain erosion–denudation and structure-denudation relief, which consists of flysch rock complexes. The geomorphological and geological setting is predisposed to extensive slope deformations––especially landslides. Slope movements play an important role in topography modelling and cause great direct and indirect damages in the countryside as well. Slope deformations of different intensity and aerial extent control the character of relief on the local or regional scale. Significant changes of land use may result from the slope movements, especially when the reclamation of the slope deformations are not undertaken. Landslides themselves have a great impact on the water regime of the landscape and consequently on the development of ecosystems. That is why they are often considered to be a significant biodiversity factor. It is also necessary to pay attention to the opposite effect since the land use (dispersed woody patches, landscape mosaic) is to a certain extent influencing the development and progress of the slope deformations. Based on the order we focused our geological investigations on the area in which the slope movements began to develop to such an extent that human lives and properties were considerably endangered. The total damages from activated landslides reached about 40 million USD. The landslide research differs in individual localities and their topical situations and is accompanied by a stability assessment of the locality and a proposal of rescue measures. An alternative solution should consist of an assessment of necessary changes in the area plans of affected villages, prospects of their future habitability, and displacements of engineering networks and roads.