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Cervinka J.,University of South Bohemia | Cervinka J.,Nature Conservation Agency of the Czech Republic | Drahnikova L.,University of South Bohemia | Kreisinger J.,Charles University | And 3 more authors.
Urban Ecosystems | Year: 2014

Although urbanization is generally considered a major threat to local and global biodiversity, some recent studies have shown that urban environments provide suitable habitat for some wildlife species, including carnivores, yet little is known about the factors that determinate their occurrence and habitat preferences. The main aim of this study was to examine the relative importance of habitat characteristics in relation to carnivore occurrence along an urban–rural gradient in the Central Europe. Carnivore occurrence was monitored using scent stations (summer period) and snow tracking (winter period) in the regional city which was divided into the network of 154 quadrates (25 ha/quadrate) for the purposes of this study. From a total of six recorded native carnivore species, the stone marten Martes foina and the least weasel Mustela nivalis were the most dominant and widespread species in both study periods. PCA analysis revealed the existence of two informative axes corresponding to (A) urban vs. non-urban habitat and (B) residential vs. industrial areas. Surprisingly, the only species exhibiting marked habitat selectivity and avoidance of highly urbanized areas was the red fox (i.e. negative correlation with the first PCA axis). The stone marten tends to avoid industrial areas and prefers residential areas; however its presence/absence was not associated with the first PCA axis. On the other hand, the ermine stoat and the least weasel were relatively unselective according to our results. In conclusion, our results demonstrate high adaptability of various species of carnivore mesopredators to urban environment; however their response to the level of urbanization and habitat characteristics exhibits interspecific variation. © 2014, Springer Science+Business Media New York. Source

Vackar D.,Charles University | Vackar D.,Academy of Sciences of the Czech Republic | Chobot K.,Nature Conservation Agency of the Czech Republic | Orlitova E.,GISAT
Landscape Ecology | Year: 2012

We test a hypothesis about the spatial coincidence of human population density and species richness, and analyze effects of land conversion and ecosystem use on species richness and landscape diversity in human dominated Central European country, the Czech Republic. We calculated fraction of aboveground net primary productivity appropriated by humans and compared it to the species richness of vertebrate, invertebrate and plant groups and to landscape diversity index in 560 mapping grid squares with grid size approximately 130 km 2. Spatial correlations and regressions were established between human population density, appropriation of net primary production, land cover and biodiversity. We found positive spatial coincidence between human population density and species richness. Although the amount of net primary production was not related to species richness in general, we found significant negative spatial relationship between ecosystem use intensity and landscape diversity. As the area of the Czech Republic exhibits relatively high land use intensities, spatial patterns of human impacts have important implications for land management and biodiversity conservation in a cultural landscape. © 2012 Springer Science+Business Media B.V. Source

Abraham V.,Charles University | Abraham V.,University of South Bohemia | Ouskova V.,Nature Conservation Agency of the Czech Republic | Kunes P.,Charles University | Kunes P.,Academy of Sciences of the Czech Republic
PLoS ONE | Year: 2014

The REVEALS model is a tool for recalculating pollen data into vegetation abundances on a regional scale. We explored the general effect of selected parameters by performing simulations and ascertained the best model setting for the Czech Republic using the shallowest samples from 120 fossil sites and data on actual regional vegetation (60 km radius). Vegetation proportions of 17 taxa were obtained by combining the CORINE Land Cover map with forest inventories, agricultural statistics and habitat mapping data. Our simulation shows that changing the site radius for all taxa substantially affects REVEALS estimates of taxa with heavy or light pollen grains. Decreasing the site radius has a similar effect as increasing the wind speed parameter. However, adjusting the site radius to 1 m for local taxa only (even taxa with light pollen) yields lower, more correct estimates despite their high pollen signal. Increasing the background radius does not affect the estimates significantly. Our comparison of estimates with actual vegetation in seven regions shows that the most accurate relative pollen productivity estimates (PPEs) come from Central Europe and Southern Sweden. The initial simulation and pollen data yielded unrealistic estimates for Abies under the default setting of the wind speed parameter (3 m/s). We therefore propose the setting of 4 m/s, which corresponds to the spring average in most regions of the Czech Republic studied. Ad hoc adjustment of PPEs with this setting improves the match 3-4-fold. We consider these values (apart from four exceptions) to be appropriate, because they are within the ranges of standard errors, so they are related to original PPEs. Setting a 1 m radius for local taxa (Alnus, Salix, Poaceae) significantly improves the match between estimates and actual vegetation. However, further adjustments to PPEs exceed the ranges of original values, so their relevance is uncertain. © 2014 Abraham et al. Source

Lorencova E.,Masaryk University | Beran L.,Nature Conservation Agency of the Czech Republic | Horsakova V.,Masaryk University | Horsak M.,Masaryk University
Malacologia | Year: 2015

The number of non-native species has dramatically increased over the last decades in many aquatic habitats of central Europe. Although the spreading of alien mollusc species can poses a serious threat to many native species, no attempt has been made to assemble and analyse an extensive dataset collected over a long time span. So far, eight non-native species of aquatic molluscs - five gastropods and three bivalves - have been recorded in the wild in the Czech Republic in central Europe. We assembled a dataset consisting of 1,783 sites with the presence of these non-native species recorded between 1891 and 2014. We aimed to explore the time course and spatial pattern of the invasions and to define some of the gross predictors of the occurrence of these species by categorizing their sites based on habitat type, elevation and distance from the nearest large river. We found that most of these species expressed affinities to non-natural standing waters and large rivers. The most invaded parts of the Czech Republic were large lowlands, especially the Elbe River basin. In contrast, hilly and mountain areas were notably less invaded as the number of records sharply decreased towards higher elevations for all studied species except Gyraulus parvus. The highest invasion rate was documented for Physella acuta and Potamopyrgus antipodarum, in contrast to two modern invaders (Menetus dilatatus and Corbicula fluminea) that had a much lower rate of colonisation. However, the other four species showing an intermediate rate of spreading were recorded for the first time both 70 years ago (Dreissena polymorpha and Ferrissia fragilis) and less than 20 years ago (Gyraulus parvus and Sinanodonta woodiana). Large rivers serve as the most important corridors for the spreading of non-native species, with a significant association between the number of non-native species recorded and the distance from the 8th- and 9th-order rivers. Source

This paper presents the results of probably the first rather detailed survey of aquatic molluscs of Rab Island. This island belongs among those Croatian islands situated in the northern Adriatic Sea. Altogether 11 species of aquatic non-marine molluscs (9 gastropods, 2 bivalves) were found at 49 sites in 2012-2015. Two species recorded, Ecrobia ventrosa and Myosotella myosotis, inhabit brackish waters while the other species belong among freshwater molluscs and were found in springs, wells, ditches, rivulets and small brooks. Kerkia kareli, a species described in 2014 from Pag Island which inhabits phreatic waters, was found at one site. The non-native Physella acuta was recorded from many sites and this find is probably the first known occurrence of a non-native aquatic mollusc at least from the northern Croatian islands. The results of this research were compared with aquatic molluscan assemblages of other Croatian islands. © 2015, Croatian Natural History Museum. All rights reserved. Source

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