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1.
Frantiek Hindák 《Hydrobiologia》2000,438(1-3):107-116
Morphological variation of trichomes, heterocytes and akinetes in four species classified into the nostocalean genera Aphanizomenon Morren ex Bornet et Flahault or Anabaena Bory (Cyanophyta/Cyanobacteria) was studied from natural samples by LM and illustrated by drawings and micrographs. All investigated species, Aphanizomenon gracile (Lemmerm.) Lemmerm., A. aphanizomenoides (Forti) Komárek et Horecká, Anabaena bergii Ostenfeld, A. minderi Huber-Pestalozzi, occur in the plankton as solitary trichomes, similar to many representatives of the genus Anabaena. Main generic diagnostic characters of Aphanizomenon and Anabaena are discussed. 相似文献
2.
Eszter Illys Milan Chytrý Zoltn Botta‐Dukt Ute Jandt Iveta kodov Monika Janiov Wolfgang Willner Ondej Hjek 《植被学杂志》2007,18(6):835-846
Question: What is the variation in species composition of Central European semi‐dry grasslands? Can we apply a training‐and‐test validation approach for identifying phytosociological associations which are floristically well defined in a broad geographic comparison; can we separate them from earlier described associations with only a local validity? Location: A 1200 km long transect running along a gradient of increasing continentality from central Germany via Czech Republic, Slovakia, NE Austria, Hungary to NW Romania. Methods: Relevés with > 25% cover of Brachypodium pin‐natum and/or Bromus erectus were geographically selected from a larger database. They were randomly split into two data sets, TRAINING and TEST, each with 422 relevés. Cluster analysis was performed for each data set on scores from significant principal coordinates. Different partitions of the TRAINING data set were validated on the TEST data set, using a new method based on the comparison of % frequencies of species occurrence in clusters. Clusters were characterized by statistically defined groups of diagnostic species and values of climatic variables. Results: Species composition changed along the NW‐SE gradient and valid clusters were geographically well separated. Optimal partition level was at 11 clusters, six being valid: two clusters Germany and the Czech Republic corresponded to the Bromion erecti; two clusters from the Czech Republic and Hungary to the Cirsio‐Brachypodion, and two clusters were transitional between these two alliances. Conclusion: The training‐and‐test validation method used in this paper proved to be efficient for discriminating between robust clusters, which are appropriate candidates for inclusion in the national or regional syntaxonomic overviews, and weak clusters, which are specific to the particular classification of the given data set. 相似文献
3.
In total, seven ciliate species were recorded in leaf-litter, moss and soil from a variety of sites in Slovakia for the first
time: Chilophrya terricola Foissner, 1984; Holostichides typicus (Song et Wilbert, 1988) Eigner, 1994; Keronella gracilis Wiackowski, 1985; Notoxoma parabryophryides Foissner, 1993; Parafurgasonia sorex (Penard, 1922) Foissner et Adam, 1981; Paragonostomum multinucleatum Foissner, Agatha et Berger, 2002, and Territricha stramenticola Berger et Foissner, 1988. The paper deals with their distribution, ecology, and comparison with similar species. The shape
and nuclear variants of Paragonostomum multinucleatum are presented and populations of P. multinucleatum and T. stramenticola are morphometrically characterized. 相似文献
4.
Ladislav Roller 《Biologia》2006,61(2):193-205
Species representation and seasonality of adult sawflies (Symphyta) were studied using Malaise traps at three submontane study
sites (Hriňová — HR, Mošovce — MO and Štefanová — ŠT) in the Western Carpathians (Central Slovakia). One trap was operated
at each study site continuously during the growing season, in MO in 1992, in HR in 1995 and in ŠT in 1996. A total of 9,281
adults representing 244 species in 9 families were collected. Very rich sawfly assemblages were found. The highest species
richness was in MO (181 species), followed by ŠT (153 species) and HR (118 species). Pseudodineura fuscula was recorded from Slovakia for the first time. Adults were present in traps from the end of April through the first half
of October. Most species occurred from the second half of May through the first half of June and finished flight activity
by the end of June. Seasonal flight activities of the 16 most abundant species are analysed and discussed. 相似文献
5.
New chromosome numbers for two species from the Senecio nemorensis group: S. dacicus (2n = 40) and S. ucranicus (2n = 40) have been ascertained. The counts for S. germanicus
Wallr. subsp. germanicus (2n = 40), S. hercynicus Herborg subsp. hercynicus (2n = 40), S. ovatus (P. Gaertn. et al.) Willd. subsp. ovatus (2n = 40) occurring in the Carpathians are also reported. The study confirmed only the known tetraploid chromosome number for
the taxa of this group. The pollen fertility ranged from 82.09 to 92.99% in all examined species and subspecies, including
their hybrids. 相似文献
6.
Changes in plant species richness at various spatial scales were investigated by manipulative experiment in mountain grasslands.
The aim of the research was to compare changes in species richness in newly abandoned sites and sites where restoration measures
were applied after 20 years of abandonment. The plots were located in two vegetation types with different moisture regime.
Species richness decreased significantly after abandonment, mainly at the finest spatial scale of 10 × 10 cm. There was significant
increase of species richness on restored sites, but it was apparent mainly at a larger scale. However, even 4 years of regular
mowing were not sufficient to restore species richness to the level typical for traditionally managed grasslands in the region.
No significant difference was found in the performance of the 2 contrasting vegetation types (wet and dry) in relation to
management measures. A significant difference in scale-dependent species richness was only observed. The dry type had a steeper
species-area curve, with a lower number of species at the finest spatial scale. According to the results of the experiment,
mountain grasslands are very vulnerable habitats, losing their conservation value quickly after abandonment. Restoration is
possible due to an extensive species pool in the region, but return to the original species richness at all spatial scales
is quite a long process. 相似文献
7.
We applied the Cocktail method to a large data set of 4 117 relevés of all Slovak vegetation types with the aim to create
formalised definitions of all Slovakian mire plant associations. We defined 21 groups of species with the statistical tendency
of joint occurrences in vegetation. These groups differed substantially in their position along the pH/calcium gradient. We
further defined 24 plant associations according to presence and/or absence of certain groups and/or strong dominance of some
species. Only six traditional plant associations were not possible to be reproduced this way. We applied our formalised definitions
to the regional data set of mires from the surrounding of the Vysoké Tatry Mts. Combined with frequency-positive fidelity
index this method has led to the classification of the majority of vegetation plots into ten associations. When the vegetation
types obtained from Cocktail-based classification and from cluster analysis were compared with respect to measured pH and
conductivity in the study region, 82% of pairs differed significantly either in pH or in water conductivity in the former
classification and 69% in the latter one. 相似文献
8.
9.
Martin Korňan 《Biologia》2009,64(1):165-179
The structure of a breeding bird assemblage of a primeval alder swamp in the Šúr National Nature Reserve (the Danube Basin)
was studied in the period 1992–1995. A 16 ha forest interior study plot was established for bird censusing. Population abundances
were estimated by a combined version of the mapping method from the end of March to the beginning of July. Altogether, 42
breeders were recorded and the mean total density of species total across years was 125.15 ± 12.73 pairs/10 ha (CV = 10.17%).
Two species were eudominant (≥ 10%): Sturnus vulgaris and Anas platyrhynchos, and six species were dominant (5% ≤ 10% <): Ficedula albicollis, Fringilla coelebs, Phylloscopus collybita, Parus major, Sylvia atricapilla, Erithacus rubecula. The Shannon diversity index (H′) varied between 3.98–4.10 bites. The evenness index (J′) reached values between 0.79–0.81. Expected species diversity in a random sample of 100 pairs calculated by rarefaction [E (S
100 pairs)] was 21.35 ± 0.92 species derived as a mean value from the years 1992–1995. The mean rarefaction estimate on the area [E (S
10 ha)] was 22.75 ± 1.58 species. Bird species richness and diversity were significantly higher in the study plot in comparison
to the mean value of European wet alder forests. These results are comparable with the values of structural assemblage parameters
of the primeval stands dominated by alder within the Białowieża National Park, Poland. 相似文献
10.
Yury Verves 《法国昆虫学会纪事》2018,54(5):410-416
Based on a revision of large recent collections housed by Czech University of Life Sciences Prague, Masaryk University, Brno, and in the private collection of Yu. Verves (Kyiv, Ukraine), new distributional data and an updated and commented list of Czech and Slovak Sarcophagidae are presented. The following six species are firstly recorded from the Czech Republic: Macronychia (s. str.) substriginervis Verves & Khrokalo, 2006, Paragusia multipunctata (Rondani, 1859), Oebalia praeclusa (Pandellé, 1895), Nyctia lugubris (Macquart, 1843), Blaesoxipha dupuisi Léonide & Léonide, 1973, and B. grylloctona Loew, 1861. As a result, 143 species of the family Sarcophagidae are currently known from the Czech Republic (109 from Bohemia and 129 from Moravia), and 131 species are known from Slovakia. 相似文献