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1.
North-west Russia, located between Ladoga and Onega Lakes and theBarents Sea, is remarkable for its high hydrological differentiation andabundance of water. The rivers and their tributaries are largely natural incharacter and with little disturbance by human activity. However, the situationis starting to change, so a biomonitoring approach has been developed to assessthe influence of land-use patterns on the structure of periphyton in thisregion. The periphyton communities in relatively pristine streams and in onesinfluenced by domestic sewage, agricultural, fish breeding farms, mineralisedmining mill wastes and other sources were analyzed in terms of speciesrichness,species diversity, species ecology values, biomass and chlorophyllconcentration.  相似文献   

2.
The pigment composition of phytoperiphyton algocenoses on stones and macrophytes (Potamogeton lucens L., P. perfoliatus L., P. gramineus L., P. pectinatus L., Mirophyllum spicatum, Petasites hybridus (L.) Gaertn., Mey. et Sxherb, Nuphar lutea L., and Alisma plantago-aquatica L.) in the submontane Sylva River (Middle Ural) is considered based on the surveys of 2000–2012. The wide variability in the content of plant pigments in phytoperiphyton depends on the season and type of substrate. The maximum values similar for all substrates are observed at the end of summer. The concentrations of Chl a increase during warm low-water years. Chlorophyll a prevails among green pigments in periphyton; the relative concentration of other pigments is lower. The concentration of plant carotenoids in epiphyton is slightly higher compared to epilithon and is comparable to the Chl a level. The trophic state index of the Sylva River may be determined as mesotrophic or weakly eutrophic when the Chl a concentration in phytoperiphyton is used as a marker.  相似文献   

3.
71 heteropteran species belonging to 57 genera of 17 families are recorded for the first time for Sverdlovsk Province (the Middle Urals). Among them, the flower bug Temnostethus longirostris (Horváth, {dy1907}) is new to the Russian fauna; the families Microphysidae, Plataspidae, and Thyreocoridae are recorded for the first time from the Middle Urals.  相似文献   

4.
New coelenterate taxa of the subclass Rugosa from the Middle Devonian of the western slope of the Subpolar Urals, the genus Syvjuphyllum (with the type species S. sokolovi gen. et sp. nov.) and the species Cosjuvia yushkini sp. nov., are described.  相似文献   

5.
An assemblage of Viséan-Serpukhovian bryozoans from the vicinity of the village of Kodinka (Sverdlovsk Region, Middle Urals) is studied for the first time. This assemblage is represented by two new species, Primorella kodinkensis sp. nov. and Heloclema uralicum sp. nov.; already known species Heloclema magnificum Gor. and Nikiforopora concentrica (Nikif.); and three morphotypes Fistulamina sp., Penniretepora sp., and Polyporella sp. Some specific features in the distribution of bryozoans of the Middle Urals at the beginning of the Carboniferous are discussed.  相似文献   

6.
The present article tests the following general assumption:plant taxa with different specializations towards mycorrhizal interactions should have different root syndromes.Roots of 61 species common in boreal zone were studied:16 species of Poaceae,24 species of Cyperaceae,14 species of Orchidaceae,and7 species of Iridaceae.Using a fixed material of 5 individuals of each species,the following was determined:number of orders of branching roots;transverse dimensions of root,stele and cortex;number ...  相似文献   

7.
As shown by sequencing the spacer rrf (5S)--rrl (23S) in 72 isolates of B. afzelii (one of the causative agents of Ixodes tick borne Borrelia infections) and the chromosomal gene coding protein P66 in 22 isolates, that in the natural focus located in the Middle Urals two different genetic subgroups (VS461 and NT28) of this genospecies simultaneously circulate. These subgroups are represented by 5 gene variants (rrf) 5S--(rrl) 23S and 5 allelic variants in gene p66. The latter, similarly to spacer gene variants, are not linked with a definite host and occur in different rrf--rrl variants of the infective agent. At the same time the definite species of vectors and carriers may be the host of several different B. afzelii variants, both in the spacer and in the gene coding protein P66, which maintains the genetic heterogeneity of B. afzelii population in the natural focus.  相似文献   

8.
9.
Aquatic macrophytes, viz. Sagittaria sagittifolia L., Lemna gibba L., Elodea canadensis Michx., Batrachium trichophyllum (Chaix.) Bosch., Ceratophyllum demersum L. and Potamogeton sp. (P. perfoliatus L., P. alpinus Balb., P. crispus L., P. berchtoldii Fieber, P. friesii Rupr., P. pectinatus L.) were collected from 11 sites for determining their metal accumulation and thiols content. Cu2+, Ni2+, Mn2+, Zn2+, and Fe3+ exceeded maximum permissible concentrations in chosen sites. Significant transfer of metals from water to leaves is observed in the order of Ni2+ < Cu2+ < Zn2+ < Fe3+ < Mn2+. The maximum variation of bioconcentration factor was noticed for manganese. The accumulation of heavy metals in leaves was correlated with non-protein and protein thiols, confirming their important role in metal tolerance. The largest contribution was provided by Cu2+ (on the average r = 0.88, p < 0.05), which obviously can be explained as an important role of these ions in thiols synthesis. Increased synthesis of thiols in the leaves allows the usage of SH-containing compounds as biomarkers of metal tolerance. Considering accumulation of metals and tolerance, B. trichophyllum, C. demersum and L. gibba are the most suitable species for phytoremediation of highly multimetal contamination, while E. canadensis and some species of Potamageton are suitable for moderately metal-polluted sites.  相似文献   

10.
The nested PCR method with primers flanking a conserved fragment of the Babesia microti ss-rDNA gene was used to examine 834 larvae of Ixodes trianguliceps ticks engorged to a varying degree, taken off 237 hosts of 12 species (rodents and insectivores). The hosts were collected in southern taiga forests in the lowmountain area of the Middle Urals (Chusovoi District, Perm Province) in 2003–2010. Babesia DNA was detected in 89 (10.7%) larvae from 8 species of small mammals. According to the data obtained by PCR and microscopic methods, either B. microti DNA or the parasites themselves were found in the blood of 45.2% of the mammals. The nucleotide sequences of 15 amplicons of Babesia DNA obtained from larvae of I. trianguliceps ticks and their hosts were identical to those of B. microti available in GenBank. In 13 cases, they were similar to B. microti US-type (a human pathogen) and in two cases (those from I. trianguliceps and from the vole Clethrionomys rufocanus from which it was removed), to B. microti of the Munich strain which is not pathogenic to humans. The duration of feeding on small mammals seems to exert the main influence on the infection rate of I. trianguliceps larvae. The fully engorged larvae contained B. microti DNA more often and usually in greater amounts than those collected during the first days of blood-sucking. The latter usually revealed Babesia DNA in the minimum quantity (< 0.064 ng/μl). According to the data obtained, transovarial transmission of Babesia in I. trianguliceps is unlikely. The processes of horizontal and transstadial transmission appear to be of crucial importance for the functioning of the natural foci of babesiosis.  相似文献   

11.
Permian Reefs of the Urals   总被引:1,自引:1,他引:0  
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12.
76 species of 44 genera from 9 subfamilies of Staphylinidae (Omaliinae, Proteninae, Pselaphinae, Tachyporinae, Oxytelinae, Steninae, Staphylininae, Paederinae, and Aleocharinae) were found in dark coniferous and broad-leaved forests in the south of Sverdlovsk Province. The ecological characteristics are presented for most species based on the original and published data. An ecological analysis of the rove beetle fauna in the southern taiga of the Middle Ural region is done.  相似文献   

13.
From 1994 to 2011, over 7000 individuals of small mammals were captured and examined for ticks in the natural foci of ixodid tick-borne borrelioses (ITBB) in the Middle Urals (Chusovskoy District of Perm Territory). Alongside with the taiga tick (Ixodes persulcatus), which is the main Borrelia vector, approximately 5700 feeding individuals of Ixodes trianguliceps have been identified. The latter species has been found to be about five times less abundant than the former. I. trianguliceps has been collected from small mammals belonging to 19 species. Its main hosts are common shrews (Sorex araneus), bank voles (Clethrionomys glareolus), and northern red-backed voles (C. rutilus). I. trianguliceps shows two seasonal peaks of abundance, spring-summer, and summer-autumn. Plating in BSK II medium yielded 72 isolates of Borrelia from a total of 1142 individuals of I. trianguliceps; 64 isolates have been identified with PCR and RFLP. The mean values of the Borrelia infestation rate in I. trianguliceps larvae, nymphs, and adults are 2.6, 10.2, and 8.1%, respectively, which is 5–10 times lower than in the taiga tick individuals collected from the same mammals. Borreliae obtained from I. trianguliceps (as well as those from I. persulcatus) have been identified as Borrelia garinii and B. afzelii, the former spirochete species being more frequent (about 90% of isolates from I. trianguliceps). Our results indicate that I. trianguliceps ticks participate in circulation of the ITBB causative agents in the forests of the Middle Urals. Rare occurrence of the tick and low rates of its infestation with borreliae suggest that the species is unlikely to play a significant role in the epizootic development in the natural foci of ITBB.  相似文献   

14.
Observations were made on the development and distribution of phytoperiphyton communities in 66 lake-river systems in NW Russia from Lake Ladoga to the Barents Sea. In total, 130 genera and 648 species were identified from different substrates, belonging to Cyanophyta (19.1%), Bacillariophyta (59.6%), Chlorophyta (18.7%), and algae from other orders (2.6%). In all streams diatoms dominated by species richness, but they were surpassed by green algae in terms of biomass. The green algae ranged from small planktonic forms to large filamentous species and produced easily visible algal communities. Among the planktonic forms the desmids were the most diverse group. They occurred in attached communities of all rivers and, while never abundant, were widespread. The attached community’s biomass was dominated by green algae. Among these, the filamentous algae Mougeotia sp., Oedogonium sp., Zygnema sp., Spirogyra sp. and Ulothrix zonata exhibited mass development in streams. Their distribution was patchy in the basin, with a total cover varying from less than 1% to 90% of the stream bottom. In some river stretches the diversity and predominance of green algae could be due, in part, to poorly developed riparian canopies. The term periphyton adopted here follows the definition of Odum (1971): “Assemblages which include both plant and animal organisms growing attached to submerged objects”. The prefix phyto- is added to indicate that of the whole biocoenoses only phototrophs are considered in this study. Presented at the International Symposium Biology and Taxonomy of Green Algae V, Smolenice, June 26–29, 2007, Slovakia.  相似文献   

15.
Martes mandibles from Late Pleistocene and Holocene sites in the Middle Urals were identified to the species level using discriminant analysis. As has been shown, sable lived there in the Late Pleistocene, with its geographic range covering all this area until the end of the 18th century; however, its range started to reduce towards the north and northeast in the early 19th century. Over 150 years, the southwestern boundary of the sable range shifted by 3° to reach the current position by the mid-20th century. The pine marten appeared in the Middle Urals in the Holocene no later than 8000 years ago and inhabits this territory at present.  相似文献   

16.
The American mink (Neovison vison) and pine marten (Martes martes) are the most common mustelid species in mountain forests of the Southern Urals. The bulk of the diet (85.3%) in the American mink consists of small mammals (35.8%), insects (22.7%), gastropods (14.1%), and fish (12.7%). In the pine marten, the main components comprising 79.6% of the diet are vegetable foods (29.8%), small mammals (27.0%), and insects (22.8%). The low diversity of their food spectra is accounted for by landscape and ecological features of the study region. The abundance of rodents is low, their distribution has a mosaic pattern, and other kinds of food are more abundant near rivers and streams, which explains the preference of both mustelid species for riparian biotopes. The breadth of trophic niches in the pine marten and American mink are 1.67 and 1.62, respectively, and the coefficient of their overlap is 0.75.  相似文献   

17.
The meiofauna community (especially nematodes, oligochaetes and chironomids) in the streambed surface of two small submountain carbonate streams (Krähenbach and Körsch, Germany) was investigated from April 1998 to March 1999. The Krähenbach stream is relatively sorted and fine-grained, while the Körsch stream is more heterogeneous and coarse-grained. The streams also differ in velocity, water level, conductivity, chloride concentration and organic content of sediment. Total meiofauna density reached a maximum value of 906 individuals per 102 cm in the Krähenbach and 3166 individuals per 102 cm in the Körsch. Rotifers were the most abundant group in the Krähenbach (52% of total fauna), whereas nematodes were dominant in the Körsch (63%). Meiofauna showed one abundance peak in the Körsch and two abundance peaks in the Krähenbach. In the Krähenbach, distinct seasonal patterns at family and species level occurred, whereas in the Körsch even at high taxonomic level only one abundance peak was observed. The most abundant nematode family in both streams were Monhysteridae, followed by Tobrilidae in the Krähenbach and by Tylenchidae in the Körsch. The dominant oligochaete family in both streams were Naididae (especially Chaetogaster langi (Bretscher, 1896) and Nais elinguis (O. F. Müller, 1773)), followed by Tubificidae. The most abundant chironomid genera in the Krähenbach were Stichtochironomus and Corynoneura. Prodiamesa olivacea (Meigen, 1818) was the dominant chironomid species in the Körsch. Deposit-feeding and detritus-feeding animals were numerically dominant in both streams. The increased mean abundance of Diplogasteridae, Rhabditidae, Tubificidae and N. elinguis in the Körsch compared to that in the Krähenbach indicates an organically enriched situation.  相似文献   

18.
The results of studies of the vegetative cover and ontogenetic composition of the cenopopulations of Picea obovata Ledeb. and Larix sibirica Ledeb. in the Gorno-Khadytinskii Forest Reserve, which is the refugium of the northern taiga forests of Western Siberia, have been summarized. According to the Brown–Blanke system, two associations of forests were identified and described, as well as two tundra associations, for comparison. The unique association of the Aconito septentrionalisPiceetum obovatae taiga forests Zaugolnova et Morozova 2009 were analyzed in detail, and a comparison of these associations was carried out in the Gorno-Khadytinskii and Pechoro-Ilychskii reserves, where these forests are the reference standards of the zonal-type forests. An estimate of the ontogenetic composition of the cenopopulations of P. obovata Ledeb. and L. sibirica Ledeb. is given, as well as the absolute age of the trees of these species.  相似文献   

19.
The species composition of desmids was studied in eight mountain lakes of the Kozhim and Malyi Patok River basins in the “Yugyd Va” National Park (subpolar Urals, Russia). A total of 98 desmid taxa representing 13 genera belonging to 4 families were identified. Geographical and ecological analyses showed that the desmid flora is typical, with a predominance of cosmopolitan species, planktic-benthic forms, acidophilic and pH indifferent species, and halophobic to salinity indifferent species. The investigated lakes can be classified as pristine and in good ecological condition on the basis of their hydrochemical and algal biodiversity characteristics. Presented at the International Symposium Biology and Taxonomy of Green Algae V, Smolenice, June 26–29, 2007, Slovakia.  相似文献   

20.
Doklady Biological Sciences - Remains of a cave bear were studied from a new locality in the Prokoshev Cave in the Middle Urals (58°13´ N, 58°12´ E). Bones from all regions of...  相似文献   

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