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41.
Structure,zonation, and species diversity of the mayfly communities of the Belá River basin,Slovakia
Four mayfly taxocoena which correspond to zones in the river continuum concept of Vannote et al. (1980) and to the zonation concept of Illies & Botoaneanu (1963), were distinguished by cluster analysis in the Belá River basin, Slovakia.By principal components analysis, taxocoena were shown to be separated along a complex gradient dominated by altitude and slope.An increase of species diversity was observed downstreams. The species-diversity data can be fitted to a geometric series, and interpreted by the niche preemption hypothesis. Equitability and the ratio of Baetidae to Heptagenidae are supposed to indicate ecological conditions. 相似文献
42.
In order to standardise biological assessment of surface waters in Europe, a standardised method for sampling, sorting and
identification of benthic macroinvertebrates in running waters was developed during the AQEM project. The AQEM method has
proved to be relatively time-consuming. Hence, this study explored the consequences of a reduction in sample size on costs
and bioassessment results. Macroinvertebrate samples were collected from six different streams: four streams located in the
Netherlands and two in Slovakia. In each stream 20 sampling units were collected with a pond net (25×25 cm), over a length
of approximately 25 cm per sampling unit, from one or two habitats dominantly present. With the collected data, the effect
of increasing sample size on variability and accuracy was examined for six metrics and a multimetric index developed for the
assessment of Dutch slow running streams. By collecting samples from separate habitats it was possible to examine whether
the coefficient of variation (CV; measure of variability) and the mean relative deviation from the “reference” sample (MRD;
measure of accuracy) for different metrics depended only on sample size, or also on the type of habitat sampled. Time spent
on sample processing (sorting and identification) was recorded for samples from the Dutch streams to assess the implications
of changes in sample size on the costs of sample processing. Accuracy of metric results increased and variability decreased
with increasing sample size. Accuracy and variability varied depending on the habitat and the metric, hence sample size should
be based on the specific habitats present in a stream and the metric(s) used for bioassessment. The AQEM sampling method prescribes
a multihabitat sample of 5 m. Our results suggest that a sample size of less than 5 m is adequate to attain a CV and MRD of
≤ 10% for the metrics ASPT (Average Score per Taxon), Saprobic Index and type Aka+Lit+Psa (%) (the percentage of individuals
with a preference for the akal, littoral and psammal). The metrics number of taxa, number of individuals and EPT-taxa (%)
required a multihabitat sample size of more than 5 m to attain a CV and MRD of ≤ 10%. For the metrics number of individuals
and number of taxa a multihabitat sample size of 5 m is not even adequate to attain a CV and MRD of ≤ 20%. Accuracy of the
multimetric index for Dutch slow running streams can be increased from ≤ 20 to ≤ 10% with an increase in labour time of 2 h.
Considering this low increase in costs and the possible implications of incorrect assessment results it is recommended to
strive for this ≤ 10% accuracy. To achieve an accuracy of ≤ 10% a multihabitat sample of the four habitats studied in the
Netherlands would require a sample size of 2.5 m and a labour time of 26 h (excluding identification of Oligochaeta and Diptera)
or 38 h (including identification of Oligochaeta and Diptera).
Electronic supplementary material Electronic supplementary material is available for this article at
and accessible for authorised users. 相似文献
43.
Marta Illyová 《Biologia》2006,61(5):531-539
The species composition, seasonal dynamic of biomass and density of zooplankton were studied in two arms with a different
hydrological regime. The samples were collected in two hydrologically different years — extremely wet in 2002 and extremely
dry in 2003. In the first arm the mean annual chlorophyll-a concentration was 31.6 μg L−1 (2002) and relatively high 64.7 μg L−1 during 2003. Mean seasonal zooplankton wet biomass was low and varied: 11.6 g m−3 (2002) and 2.93 g m−3 (2003). Total zooplankton density was high (7,370 N L−1) in 2002, when rotifers predominated in an open water zone and contributed up to 81% of the total zooplankton biomass and
83% of the total zooplankton density. In medial and littoral zone, in total, 22 cladoceran and 15 copepod species were identified.
In the second arm the mean annual concentration of chlorophyll-a was high: 74.8 μg L−1 (2002) and 61.4 μg L−1 (2003). Mean seasonal zooplankton wet biomass varied from 92.5 g m−3 (2002) and 44.10 g m−3 (2003). In 2002 the planktonic crustaceans predominated; their mean biomass was 87.1 g m−3 and B. longirostris formed more than 91% of this value. In 2003, the zooplankton density was high (15,687 N L−1), when rotifers contributed up to 94% of this value. The boom of rotifers (58,740 N L−1) was recorded in June 2003. In total, 45 cladoceran and 14 copepod species were recorded in the medial and littoral zones.
During observation we concluded that the structure of zooplankton, particularly species composition, abundance, biomass and
seasonal dynamics are affected by the fluctuation of water levels in the arms of the rivers’ inundation areas. This unstable
hydrological regime prevented the development of planktonic crustaceans. 相似文献
44.
The morphometrics and reproduction of shrews (Sorex araneus, S. minutus, S. alpinus) was studied in Slovakia. Significant differences in weight, body length and tail length were recorded in adult and subadult
shrews. Adult individuals and males had higher mean somatometric values (apart from tail length of subadults). The hind foot
length was the least variable characteristic, which can be considered as the most stable taxonomic somatic characteristic
of shrews. Weight and body length varied considerably. Values of somatic characteristics in S. araneus and S. minutus increased with increasing altitude, apart from hind foot length in S. araneus, which decreased with increasing altitude. The values of somatic characteristics declined with increasing continentality,
but tail length gradually increased in the direction west — east at the highland level. Sorex minutus was characterized by the greatest reproductive activity (length of reproductive cycle April–October, average number of embryos
6.97). The lowest reproductive activity was observed in S. alpinus (average number of embryos 5.72). The mating season of S. araneus began at the end of March and ended in August with an average number of embryos of 6.12. 相似文献
45.
46.
Question: What are the main broad‐scale spatial and temporal gradients in species composition of arable weed communities and what are their underlying environmental variables? Location: Czech Republic and Slovakia. Methods: A selection of 2653 geographically stratified relevés sampled between 1954–2003 was analysed with direct and indirect ordination, regression analysis and analysis of beta diversity. Results: Major changes in weed species composition were associated with a complex gradient of increasing altitude and precipitation and decreasing temperature and base status of the soils. The proportion of hemicryptophytes increased, therophytes and alien species decreased, species richness increased and beta diversity decreased with increasing altitude. The second most important gradient of weed species composition was associated with seasonal changes, resulting in striking differences between weed communities developed in spring and summer. In summer, weed communities tended to have more neophytes, higher species richness and higher beta diversity. The third gradient reflected long‐term changes in weed vegetation over past decades. The proportion of hemicryptophytes and neophytes increased, while therophytes and archaeophytes decreased, as did species richness over time. The fourth gradient was due to crop plants. Cultures whose management involves less disturbances, such as cereals, harboured less geophytes and neophytes, and had higher species richness but lower beta diversity than frequently disturbed cultures, such as root crops. Conclusions: Species composition of Central European weed vegetation is mainly influenced by broad‐scale climatic and edaphic factors, but its variations due to seasonal dynamics and long‐term changes in agricultural management are also striking. Crop plants and crop‐specific management affect it to a lesser, but still significant extent. 相似文献
47.
Fischer OA Matlova L Dvorska L Svastova P Bartos M Weston RT Kopecna M Trcka I Pavlik I 《Medical and veterinary entomology》2005,19(4):360-366
The syrphid Eristalis tenax Linnaeus (Diptera: Syrphidae) may be found in and around dung storage pits at cattle farms at various developmental stages of their life cycle. The purpose of this study was to investigate the occurrence of Mycobacterium avium ssp. paratuberculosis in 1044 E. tenax samples at various developmental stages, as well as fresh and stored dung originating from nine cattle farms. Mycobacterium fortuitum was isolated from one (1.5%) larva from the vicinity of three paratuberculosis-free herds of cattle. Mycobacterium a. paratuberculosis was isolated from 111 (21.4%) of E. tenax larvae collected from two of seven farms known to be infected with the causal agent of paratuberculosis. Mycobacteria were not isolated from any of the 340 pupae, 41 adults of 78 samples of exoskeletal exuviae. Mycobacterium a. paratuberculosis isolates from E. tenax larvae were of the IS900 restriction fragment length polymorphism (RFLP) type B-C1, identical to that detected in faecal samples from cattle herds infected with paratuberculosis. Larvae artificially infected with mycobacteria of IS900 RFLP type B-C9 did not contain statistically more CFU of identical IS900 RFLP type B-C9 in the intestinal tract and internal organs than on the body surface. These results show that M. a. paratuberculosis can survive in the intestinal tract and internal organs of E. tenax. 相似文献
48.
A putative upupiform bird from the Early Oligocene of the Central Western Carpathians and a review of fossil birds unearthed in Slovakia 下载免费PDF全文
An isolated hind limb of a miniature bird from an Early Oligocene locality (30–34 Ma) near Bystré (Slovakia) is described and analyzed. The tarsometatarsus (TMT) of the specimen is remarkably short relative to the tibiotarsus. When relative length ratios of the bones are compared with a sample of 29 extant and extinct birds with short metatarsi, the specimen variably clusters with some alcedinids, coraciids and trochilids. Log‐clusters give less ambiguous results and indicate significant proximity of the Bystré specimen to the extinct messelirrisorids (Upupiformes) and the recent acledinids (Coraciiformes). With regard to morphological details, such as those of the first metatarsal, II‐IV metatarsal trochleae, intertrochlear incisurae and phalanges, the Slovak specimen shows a combination of features, which are distributed among recent upupiforms and coraciiforms as well as extinct upupiforms (Messelirrisor) and apodiforms (Eocypselus, Parargornis). Taken together, the metric and morphological data sets suggest that the specimen from Bystré is a coraciiform sensu lato rather than an apodiform bird. Within the Coraciiformes, the robust trochlea of MT‐I with expanded dorsal shelf, the large medial and slit‐like lateral intertrochlear incisura, and the long hindtoe suggest upupiform rather than alcedinid relationships. 相似文献
49.
The Carabidae (Coleoptera) are a useful tool for monitoring the effects of different types of control and theretofore it is important to highlight about their role as possible ecological indicators. We studied the composition of carabids in ecological and integrated farming, in three different crops in southern Slovakia. The ground beetles were caught using pitfall traps during a period of three years, from 2018 to 2020. 7 801 adult carabids belonging to 26 species were collected and recorded altogether. The number of species varied from 11 to 15 between traps. The distribution and number of individuals were positively influenced by ecological management with the amount of 4784 individuals, compared to integrated management, where 3017 individuals were obtained. The influence of the crops was in the following order: Triticum aestivum, Pisum sativum and Medicago sativa. In both farming systems, representatives of the Carabidae family were almost the same species. The most abundant species of the pooled number was Harpalus rufipes (from 61.16 to 88.08%). Brachinus crepitans also dominated (from 5.98 to 16.47%). Other species were Poecilus cupreus, Anchomenus dorsalis, Brachinus explodens. The species identity index according to Jaccard when comparing both farming types for the observed period reached 60.00%. The average comparison of the identity of dominance for the observed period of ecological vs integrated management represents 90.39%. The Shannon-Weaver diversity index for ecological farming was 0.9957 and 1.0184 for integrated farming. 相似文献
50.
The 1997 check list of Dolichopodidae of the Czech Republic and Slovakia has recently been reviewed and updated. The new species
list includes 346 species with 22 species added as new to the fauna of the Czech Republic. While the check list itself is
published elsewhere, largely unpublished new records of Hercostomus argentifrons, H. nigrilamellatus, Medetera adjaniae, M. melancholica and M. setiventris are presented here, together with data on their distribution in Europe and their biology and ecology. The status of the newly
added Sympycnus desoutteri is discussed. H. argentifrons is recorded here for the first time from the Czech Republic (Bohemia; Moravia) and background information is given on its
discovery. While the Czech fauna with 324 species can be considered well known, the fauna of Slovakia is definitely much richer
than its current national list of 217 species suggests. In the latter country, in particular surveys of sandy habitats with
heathland or peatmoor, saltmarshes, reedmarshes, humid forests on loamy soils, and of rothole and saprun microhabitats on
trees might quickly yield new species records. 相似文献