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1.
Diploid hybrid plants (2n = 18) between sexual diploid cytotypes of Hieracium alpinum and H. umbellatum were found in the Ukrainian Eastern Carpathians. They were identified with H. × grofae Woł., originally used for the combination H. decipiens × H. umbellatum var. lactaris. As H. decipiens sensu Woł. (non Tausch) does not produce viable pollen grains and is most probably a polyploid apomict, it is unlikely to produce diploid hybrid plants with diploid H. umbellatum. Both parent species, Hieracium alpinum and H. umbellatum are also given by Wołoszczak from the original locality. Thus we conclude that H. × grofae is result of hybridization between H. alpinum and high mountain form of H. umbellatum. Hybrid plants are morphologically intermediate between the parent species, and moreover resemble closely or they are identical with the experimental hybrids of the same parent combination. Hybrids produce rather high amount of homogeneously sized pollen grains (values of standard deviation and coefficient of variation lower then upper limits for diploids — 3μm or 7.5%, respectively), and might probably serve as male parents in further crosses; on the other hand, they are fully seed-sterile. A lectotype of H. × grofae, a second proved nothotaxon in the genus Hieracium s.str., is designated. Localities of H. × grofae are located in subalpine belt of the Marmarosh Mts, the Svydovets’ Mts and the Horhany Mts (all in the Ukrainian Eastern Carpathians). Biotopes of hybrid plants usually represent secondary formed and disturbed pastures allowing close contact of altitudinally vicariant parent taxa.  相似文献   

2.
Oligochaeta, occurring in the littoral zones of two sand pits, were sampled in order to determine the relationship between the oligochaete species and the waters’ trophic level. Differences between sand pits attributable to community structure and to an overall higher abundance of oligochaetes, especially tubificids, were observed in Dzierżno Małe. Multivariate analyses (correspondence analysis [CA] and canonical correspondence analysis [CCA]) reveal correlations between the distribution patterns of oligochaete species and the concentration of nitrates, phosphates and dissolved oxygen. Some species, e.g. Dero digitata, Limnodrilus hoffmeisteri, Potamothrix hammoniensis, Nais simplex, Limnodrilus claparedeanus, Limnodrilus udekemianus and Tubifex tubifex, were more abundant in eutrophic sites. The results of the study showed that the richness of Oligochaeta species is not a good method for estimating the trophic levels of the studied sand pits. Indicators based on the share of oligo-, meso- and eutrophic species in Oligochaeta communities are better for evaluating the water quality in the studied reservoirs.  相似文献   

3.
 The dynamics and abundance of nectar secretion as well as sugar productivity were studied in flowers of brown mustard (Brassica juncea) cv. Małopolska and white mustard (Sinapis alba) cv. Borowska. Moreover, floral nectaries were examined under LM and SEM. In both cultivars lateral and median pairs of nectaries secreted nectar. However, differences were found in morphology and activity of these pairs. The lateral nectaries produced more nectar than the median ones. Nectar secretion started at loose bud and peaked during anther dehiscence. Average amount of nectarsecreted by 100 flowers of cv. Małopolska and cv. Borowska were 119.9 mg and 134 mg. Mean concentration of nectar was 26.7% and 23.4%, respectively. One hundred flowers of cv. Małopolska and cv. Borowska secreted 28.4 mg and 24.9 mg of sugars in nectar. Estimated sugar productivity per 1 ha of crop was 65.5 kg and 71.2 kg, respectively. Received August 28, 2002; accepted November 2, 2002 Published online: June 2, 2003  相似文献   

4.
The pheromone-responsive Gβ subunit of Saccharomyces cerevisiae (encoded by STE4) is rapidly phosphorylated at multiple sites when yeast cells are exposed to mating pheromone. It has been shown that a mutant form of Ste4 lacking residues 310–346, ste4Δ310–346, cannot be phosphorylated, and that its expression leads to defects in recovery from pheromone stimulation. Based on these observations, it was proposed that phosphorylation of Ste4 is associated with an adaptive response to mating pheromone. In this study we used site-directed mutagenesis to create two phosphorylation null (Pho) alleles of STE4: ste4-T320 A/S335A and ste4-T322 A/S335A and ste4-T322A/S335A. When expressed in yeast, these mutant forms of Ste4 remained unphosphorylated upon pheromone stimulation. The elimination of Ste4 phosphorylation has no discernible effect on either signaling or adaptation. In addition, disruption of the FUS3 gene, which encodes a pheromone-specific MAP kinase, leads to partial loss of pheromone-induced Ste4 phosphorylation. Two-hybrid analysis suggests that the ste4Δ310–346 deletion mutant is impaired in its interaction with Gpa1, the pheromone-responsive Gα of yeast, whereas the Ste4-T320A/S335A mutant has normal affinity for Gpa1. Taken together, these results indicate that pheromone-induced phosphorylation of Ste4 is not an adaptive mechanism, and that the adaptive defect exhibited by the 310–346 deletion mutant is likely to be due to disruption of the interaction between Ste4 and Gpa1. Received: 14 February 1998 / Accepted: 28 February 1998  相似文献   

5.
The genus Phrixolepia Butler, 1877 is revised and its diagnosis is given. At present, the genus comprises 10 species, three of which are described as new (all the holotypes and paratypes are deposited in MWM): Ph. pudovkini Solovyev, sp. n., LT: “China, Shaanxi prov., Taibai Shan, Tsinling Mts., Houzhenzi, 33°53′ N; 107°49′ E, 1500 m,” genital slide 11389; Ph. sinyaevi Solovyev, sp. n., LT: “N. Vietnam, Cuc. Phuong, 60 km SW Hanoi, 20°15′ N; 105°20′ E, 400 m,” genital slide 11386; Ph. nigra Solovyev, sp. n., LT: “China, prov. Yunnan, Yunlong, Fengshuining Mts., 13 km N of Caojian, 2460 m,” genital slide 11391. All the species are very similar externally, except for differences in size, tints of the coloration, and the presence of a semi-ovoid bright apical spot in the fore wing. The features of the male genitalia are diagnostic. A key to the species is given. The phylogenetic relationships between the species are examined. The genus is closely related to Olona Snellen, 1900 and Phobetron Hübner, 1825, based on the characters of larval morphology. A similar larval morphology also found in the family Dalceridae could be a synapomorphy of the families Limacodidae and Dalceridae.  相似文献   

6.
An analysis of long-term changes in abundance of hibernating bats as revealed from the annual monitoring programme conducted in four mountain regions of the Western Carpathians (Muránska planina Mts, Revúcka vrchovina Mts, Slovensky kras Mts, Štiavnické vrchy Mts) during the period 1992–2009 is providing in the paper. Data from 52 hibernacula were analysed. Among 18 bat species recorded, an apparent population increase of three most abundant thermophilous and originally cave dwelling species of bats, Rhinolophus hipposideros, R. ferrumequinum, Myotis myotis, was observed. In other bat species (e.g., R. euryale, M. emarginatus, M. mystacinus, M. dasycneme, Barbastella barbastellus), population trends could not be detected and because of data scarcity, they should be evaluated from more extensive datasets obtained from a wide range of hibernacula or from a completely different type of evidence.  相似文献   

7.
Katarína Holcová 《Biologia》2008,63(6):1143-1156
From 1999–2005, seventy-eight samples were collected from the small streams in the area of the Boubín Mountain including also the natural preserve “Boubínsky prales” (Boubín primeval forest) (Šumava Mts, Czech Republic). Nineteen species of thecamoebians were identified in the samples; the most abundant species were Centropyxis orbicularis, Pontigulasia compressa, Centropyxis aculeata, Difflugia oblonga and Centropyxis arcula. Species composition of assemblages as well as ecological affinities of the most common taxa are comparable with data from the previously analysed streams in the Šumava Mts. This correlation improves the quality of data for environmental preferences of thecamoebian assemblages contained in the streams and these can be used for interpretation of ancient environments. Though species composition of assemblages changes gradually, two end-member assemblages can be defined. For both assemblages, environmental conditions were defined: Lower-diversity assemblages dominated by centropyxids originated mainly from standing water with low content of organic debris. Relative abundances of C. orbicularis showed negative correlations with abundances of other Centropyxis spp. which may indicate different ecological affinities of this species. Centropyxis orbicularis may tolerate higher levels of fine organic debris in stream sediments. Assemblages with common to abundant occurrences of P. compressa and/or D. oblonga prefer running water. Difflugia oblonga dominated in samples with higher content of fine organic debris. Relation between test size of D. oblonga and flow rate was recorded: large D. oblonga prevailed in standing water while small specimens dominated in fast streams.  相似文献   

8.
Bats were netted at two sites over the forest rivers Narewka and Hwoźna in Białowieża Primeval Forest (E Poland), during the summer of 1994 and 1995. A total of 452 bats of 11 species were captured. The number of bats netted each night was positively correlated with the minimum air temperature. The rate at which the three commonest species —Nyctalus noctula, Myotis daubentonii andNyctalus leisleri — were caught varied significantly through the night, with a major peak after sunset. ForN. noctula air temperature was apparently positively related to the size of the morning peak.  相似文献   

9.
We studied Orthoptera, Dermaptera, and Blattodea of the Białowieża Forest (Poland) in order to assess (1) the minimum patch size of open habitat necessary for each species, (2) the role of linear corridors as habitat, and (3) the impact of herbivores on diversity by comparing the fauna at periods of different ungulate densities. Many species occurred in the farthest clearings from the forest edge to arable land. Two third of species occurred in clearings smaller than 10,000 m2. Dry linear corridors of 10–40 m width and wet linear corridors of 100–200 m width had a species richness that corresponded to that of clearings of about 10,000 m2. Four species disappeared from the Białowieża Forest when ungulate density decreased from 20 individuals/km2 (3000 kg/km2 biomass) at the beginning of the 20th century to 10 individuals/km2 (1000 kg/km2) at the end of the 20th century. We conclude that most Orthoptera, Dermaptera, and Blattodea species could survive in Central Europe if human land use was replaced by intensive grazing and browsing by wild herbivores.  相似文献   

10.
Diatom communities of acidic mountain streams in Poland   总被引:1,自引:0,他引:1  
Kwandrans  Janina 《Hydrobiologia》1993,269(1):335-342
A comparison has been made of the species composition of diatom communities developing in acidic Polish mountain streams which flow over calcium-poor substrates: sandstones in the Silesian Beskid (section of the Western Carpathians), the witokrzyskie Mts, and over granite in the Karkonosze range (in the Sudetic Mts). The number of taxa and diversity of the diatom assemblages decreased along a decreasing pH gradient. The correlation between pH and the number of taxa was positive and significant (r 2 = 0.69, p < 0.005). A small number of species (< 20) and low diversity were found in the communities developing in strongly acidic streams such as in the witokrzyskie Mts with pH 4.1–5.2, and in the Silesian Beskid with pH 3.5–4.0. In the stream of the Karkonosze Mts, with pH 5.2–6.0, the communities were characterized by their greater number of species and higher diversity.Acidobiontic and acidophilous diatoms were generally dominant. The pH-indiferent forms were less abundant, and their proportion increased above pH 5.0. Eunotia exigua, E. paludosa var. trinacria, E. tenella and Pinnularia subcapitata dominated in streams with the lowest pH, while E. exigua, E. sudetica and Achnanthes kryophila predominated in a stream with water pH above 5.2. Eunotia exigua, a common acidobiontic species was present in all the examined communities, and was a strong dominant in waters of pH 5.0. A corresponding decrease in abundance of E. exigua was observed with an increase in pH.  相似文献   

11.
Taraxacum pieninicum Pawł. (Asteraceae) is an endemic species, growing only in Pieniny Mts. The aim of the presented work was to investigate its pollen morphology as well as its ultrastructural traits of achene pericarp. Pollen grains of this species were of medium size, echino-lophate and 3-zonocolporate. The external surface of the achene body was of scale sculpture, covered with the spikes. Pappus hairs were not branched, built of a few tubular cells, with acute, protruding ends.  相似文献   

12.
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   

13.
Blood parasites of small mammals living in Białowieża Forest (eastern Poland) were investigated between 1996 and 2002. The following haemoparasite species were found:Trypanosoma (Herpetosoma) evotomys in bank voleClethrionomys glareolus; T. (H.) microti in root voleMicrotus oeconomus; Babesia microti in root vole;Hepatozoon erhardovae in bank vole andHepatozoon sp. in root vole. Some non-identifiedBartonella species were found in bank vole, root vole, field voleMicrotus agrestis, yellow-necked mouseApodemus flavicollis, common shrewSorex araneus, Eurasian water shrewNeomys fodiens, and Mediterranean water shrewN. anomalus. The prevalence and diversity of blood parasites were lower in shrews than small rodents. Totally, 52.0% of bank voles, 50.0% of root voles, 32.5% of common shrews, and 41.2% of Eurasian water shrews were infected with any of the blood parasites. Mixed infections were seldom observed in bank vole (17.3% of investigated individuals) and root vole (14.7%). No animals were infected with three or four parasites simultaneously. Infection of Białowieża small mammals with haemoparasites seemed to be similar to those described in other temperate forest regions rather than boreal ones. Infection rates of rodent species seem to be higher in their typical habitats: for bank vole it was the highest in mixed forest, whereas for root vole in sedge swamp. The results suggest that Arvicolidae play a greater role than Muridae or Soricidae in maintenance ofBabesia andHepatozoon foci in natural environments of central Europe.  相似文献   

14.
The material for this study was obtained from culled European bison (Linnaeus, 1758) originating from both captive breeding and free-ranging populations in Białowieża and Borecka Forests (north-east Poland), and was mostly collected from November until April. Mass difference between the right and left testis of the same individual up to 30% was considered to be physiological asymmetry, which proved typical of the species. Hypoplasia or atrophy of the testes exceeding 30% in size, were found in 37 males (13.6% of the examined animals;n=272). Cryptorchidism was recorded in 20 bison culled in Białowieża Forest at the age over 1 year (10.6% of individuals at the same age;n=188). We registered the weight of testes of 259 males aged 2 months to 20 years. In the examined males, no distinct predominance in size and weight between the right and left testes was observed. The weight of testes was significantly correlated with age (r=0.85,p < 0.0001) and body weight (r=0.93,p < 0.0001). The heaviest testicles belonged to older and sexually mature bulls aged 6–12 years (mean 216 g) and to old ones over 13 years (mean 242 g). Two testis measurements (length and width) were taken from 136 culled males, while two additional measurements (total length with the cauda of epididymis and circumference) from 65 males. The length and width of the testes were moderately correlated with age (r=0.31 andr=0.20,p < 0.01) and highly significantly correlated with testis (r=0.79,p < 0.001) and body weight (r=0.92,p < 0.001).  相似文献   

15.
Hypotheses about the dependence of circadian activity from metabolic rate and the segregation of temporal niches among competing species were verified by the study of activity patterns in a shrew community of two semiaquatic species,Neomys anomalus Cabrera, 1907 andN. fodiens (Pennant, 1771), and two terrestrial species,Sorex araneus Linnaeus, 1758 andS. minutus Linnaeus, 1766, co-existing in wet habitats of Białowieża Forest (E Poland). In ten trapping sessions, performed in early summer between 1991 and 2000, traps were open 24 hours continuously and patrolled at 1:00, 5:00, 10:00, 15:00, and 20:00. All the shrew species were most active between 20:00 and 1:00, and least active around mid-day (10:00–15:00). However, activity of the twoSorex species was lower than that of the twoNeomys species in the period 20:00–1:00, but higher in the period 15:00–20:00. BothNeomys species displayed clearly nocturnal, unimodal patterns of activity. In contrast, activity of bothSorex species was relatively evenly distributed over 24 hours and they increased their activity earlier (ie after 15:00) than bothNeomys species (after 20:00). These results confirm the idea that small shrew species with higher metabolic rate have more frequent and more equally distributed activity bouts than large species. Overlap of temporal niches was the highest within genera (99.29% between bothNeomys species and 98.36% between bothSorex species), the lowest betweenN. fodiens andS. araneus (88.26%) andS. minutus (89.34%), and intermediate betweenN. anomalus and bothSorex species (91.78 and 93.34%, respectively). Such high interspecific overlaps in activity suggest a joint-action of other mechanisms that separate ecological niches of these species also in other dimensions (eg food, microhabitat).  相似文献   

16.
A profile of free fatty acid (FFA) specificity in Acanthamoeba castellanii mitochondrial uncoupling is described. The FFA uncoupling specificity was observed as different abilities to stimulate resting respiration, to decrease resting membrane potential, and to decrease oxidative phosphorylation efficiency. Tested unsaturated FFA (C18–20) were more effective as uncouplers and protonophores when compared to tested saturated FFA (C8–18), with palmitic acid (C16:0) as the most active. As FFA efficiency in mitochondrial uncoupling is related to physiological changes of fatty acid composition (and thereby FFA availability) during growth of amoeba cells, it could be a way to regulate the activity of an uncoupling protein and thereby the efficiency of oxidative phosphorylation during a cell life of this unicellular organism. Aleksandra Swida and Małgorzata Czarna contributed equally to this work.  相似文献   

17.
Various species of large predators are reported to influence each other through interference or exploitation competition that may affect demography and survival of the subordinate species. We analyzed spatial relationships between grey wolf (Canis lupus) and Eurasian lynx (Lynx lynx) in Białowieża Primeval Forest (BPF, eastern Poland) to determine how they partitioned the space. The wolves (= 8) and lynx (n = 14) were radio-tracked in 1991–1999. Three wolves and seven lynx were radio-tracked simultaneously in 1994–1996. Territories of wolf packs and home ranges of lynx overlapped considerably (76% of wolf territories and 50% of lynx home ranges, on average). In three cases, their core areas were also overlapping. Wolf-lynx dyads with overlapping home ranges were simultaneously located at distances from 0 to 28 km from each other. We found neither avoidance nor attraction between wolves and lynx occupying the same areas. We concluded that in BPF, the two large predators coexist due to specialization on different preferred prey and heterogeneous habitat.  相似文献   

18.
19.
The molecular population structure of 20 populations of the subalpine plant Gentiana pannonica was studied by use of amplified fragment length polymorphism (AFLP) and sequencing of non-coding regions of plastid DNA. Of the populations sampled, 18 were native (11 were from the Eastern Alps, which is the distribution centre of the species, and seven were from the Bohemian Forest, which is on the margin of the distribution range), and two were from the Giant Mts and of unclear status. No plastid DNA polymorphisms were found within the entire 6,185?bp investigated. The AFLP data revealed grouping of populations at the regional level. However, differentiation at the regional level (10.3?%) and at the interpopulation level (14.2?%) was low. Even though current populations are isolated and contain small numbers of individuals, the within-population variation (75.511?%) was high. Genetic variation was higher for alpine populations than for Bohemian Forest populations, probably because of fundamental differences in historical changes in population size between these regions. Within-population variation was intermediate for populations in the Giant Mts. The results indicate the possibility of a large distribution of species in the unglaciated areas of Central Europe, irrespective of altitude, during the late Pleistocene and early Holocene. Our results do not confirm that G. pannonica was introduced in the Giant Mts, and native status in the Giant Mts is possible.  相似文献   

20.
Measurements of dependence of photosynthetic electron transport on irradiance and analyses of stable isotope ratios (δ18O, δ13C, δ15N) were performed on 4 to 6-year-old pine trees (Pinus sylvestris L.) in the primeval forest reserve of Białowieża and on 21-year-old pine trees of a plantation of different provenances at the Sękocin Forest Station near Warsaw, Poland. Small differences in maximum photosynthetic electron transport rates, ETRmax were related to growth. Stable isotope analyses suggest that water relations play an important role for the performance of P. sylvestris at the sites studied. The intraspecific comparisons showed a very high variability of photosynthetic capacity between needles of given trees and between individual trees under similar conditions. Differences between specific provenances were also observed. This is relevant for ecological niche occupation in a wide geographical growth range, where P. sylvestris is actually occurring. The high physiological plasticity demonstrated reveals a conspicuous trait of this tree species.  相似文献   

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