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1.
European dry grasslands formed of the Festuco-Brometea type are among the most diverse plant communities within agricultural landscapes. We examined floristic composition, functional trait structure and threatened species occurrence in grasslands of this type from in two distinct biogeographic regions, Dinaric (NW Balkan) and the Central European. In the Central European region this type of grassland is threatened by a decline in traditional extensive management. We tested, if differences in the level of threat between regions are matched by differences in community-weighted means for resource use strategy traits and occurrence of Red List (threatened) species. We then tested if threatened species differed in their traits from other species and if threatened species richness was related to CWM for resource use strategy traits. The communities from the Central European region had significantly higher SLA and lower LDMC, which perhaps reflects an increase in intensive agriculture promoting fast-growing species. Threatened species occurrence did not differ significantly between regions, but threatened species richness was significantly negatively correlated with CWM for height and SLA. This may suggest that threatened species are less likely to occur in high productivity communities where light competition is intense. This study provides initial evidence that changes in CWM for resource use strategy traits may provide a useful means for predicting threatened species loss in dry grassland ecosystems.  相似文献   

2.
Alvar grasslands are thin-soil calcareous grasslands on Silurian and Ordovician limestone bedrock. They are considered unique plant communities for northern Europe and America with a high conservation value. Until now, European alvar grasslands have only been described in Sweden and Estonia. We described species-rich alvar grasslands on the Izhora plateau, NW Russia and compared this vegetation with that of Estonian alvar grasslands. Floristic composition and environmental conditions of Russian alvars were similar to Estonian alvar grasslands on thicker dry soil. Russian alvars are isolated from similar communities in Estonia, but extensive transport of domestic animals from Estonia to NW Russia in past centuries has probably enhanced species dispersal. Some characteristic Estonian alvar species were missing in NW Russia because it lies outside their natural ranges. Other differences in vegetation were explained by higher atmospheric nitrogen deposition and younger age of Russian sites. In NW Russia the alvar grasslands were small, but several red-listed plant species were present. In order to preserve European alvar vegetation effectively, Russian alvar grasslands need further study and conservation as an outpost of this threatened vegetation type.  相似文献   

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The phylogeography of the European wild boar was mainly determined by postglacial recolonization patterns from Mediterranean refugia after the last ice age. Here we present the first analysis of SNP polymorphism within the complete mtDNA genome of West Russian (n = 8), European (n = 64), and North African (n = 5) wild boar. Our analyses provided evidence of unique lineages in the East‐Caucasian (Dagestan) region and in Central Italy. A phylogenetic analysis revealed that these lineages are basal to the other European mtDNA sequences. We also show close connection between the Western Siberian and Eastern European populations. Also, the North African samples were clustered with the Iberian population. Phylogenetic trees and migration modeling revealed a high proximity of Dagestan sequences to those of Central Italy and suggested possible gene flow between Western Asia and Southern Europe which was not directly related to Northern and Central European lineages. Our results support the presence of old maternal lineages in two Southern glacial refugia (i.e., Caucasus and the Italian peninsula), as a legacy of an ancient wave of colonization of Southern Europe from an Eastern origin.  相似文献   

5.
Using isoenzyme analysis, 35 populations of Juniperus communis L. from various parts of the Russian species range and by one population from Sweden and Alaska were studied. The total sample size was 1200 plants. As a result, the existence of J. communis var. oblonga in North Caucasus and J. communis var. depressa in North America was confirmed, but genetic differences between J. communis var. communis and J. communis var. saxatilis were not detected in the main part of the Russian species range (European part of Russia, Ural, Siberia). These populations proved to be genetically uniform with the same predominant allelic frequencies, which may evidence recent settling of this species from one of Central or East European refugium. J. communis var. saxatilis from northeastern Russia inhabiting the region behind Verkhoyansk mountain and Russian Far East showed considerable differentiation in frequencies of alleles at three loci and geographical subdivision. These populations also exhibit high intrapopulation variation. This can be connected with the refugium in this territory. The origin of this group is probably connected with migrations from Central Asia (Tibet) in the direction to northeastern Russia along mountains connecting Central and North Asia. It is also assumed that migrations of this species previously proceeded across the Beringian land bridge.  相似文献   

6.
Phytoplankton data from 606 lakes were used to characterize indicator taxa of near-pristine reference conditions in clearwater and humic lowland lakes of Northern and Central Europe. Reference lakes were selected based on low pressure from catchment land-use, low population density and the absence of point sources. Reference lakes had low phytoplankton biomass and taxa richness compared to non-reference lakes. In low alkalinity lakes of Northern Europe, the reference communities had high biomass proportions of chrysophytes and low proportions of cyanobacteria; in the Central European high alkalinity lakes, the biomass was distributed more evenly among algal groups. Indicator species analysis and similarity analysis listed 5–29 taxa indicating reference conditions. Indicator taxa differed especially between the low alkalinity and the high alkalinity lakes, but there were also country-specific differences. Most common indicator taxa for the northern reference lakes were chrysophytes (e.g. Bitrichia, Dinobryon). In the Central European reference lakes, diatoms (e.g. Cyclotella) were more characteristic. Despite the differences, there was a general finding that taxa present in reference lakes were often also present in non-reference lakes, but typically in lower biomass proportions; another characteristic of the reference communities is the absence of many taxa typically found in non-reference lakes.  相似文献   

7.
32-bp inactivating deletion in the β-chemokine receptor 5 (CCR5) gene, common in Nothern European populations, is associated with reduced HIV-1 transmission risk and delayed disease progression. We have studied the deletion distribution in many populations in Eurasia by polymerase chain reaction analysis of 531 DNA samples representing West and East Siberian, Central Asian, and Far Eastern parts of Russia. An unusually high frequency (11.1%) of the deleted variant in natives of West Siberia, of Finno-Ugrian descent, was observed. Furthermore, the deletion was infrequent in indigenous populations of Central Asia, East Siberia, the Russian Far East, and Canada. We conclude that the Δccr5 distribution is limited primarily to Europeans and related western Siberian Finno-Ugrian populations, with a sharp negative gradient toward the east along the territory of Russian Asia. Received: 22 December 1997 / Accepted: 24 March 1998  相似文献   

8.
For the first time, an analysis of five Alu insertion loci (ACE, APOA1, B65, PV92, TPA25) has been carried out in 10 Russian populations (1088 individuals) covering the whole historical area of the Russian ethnos. Depending on the locus, Russian populations exhibit similarity to their Western (European populations) or Eastern (populations of the Ural region) neighbors. Considering the frequencies of the studied Alu-insertions, the Russian gene pool exhibits low variation: average interpopulation variation (d) was 0.007, whereas on classical markers, mtDNA and Y chromosome, heterogeneity of the Russian gene pool is essentially higher (0.013, 0.033, 0.142, respectively). Therefore, on the intra-ethnic level, this set of five Alu insertions has low variation. However, a clear pattern was obtained in inter-ethnic comparison of 13 East European ethnic groups, which formed three clusters in accordance with their historical and geographical position: East Slavic, Caucasian and South Ural clusters. The obtained data confirm the efficiency of using Alu insertions for studying genetic differentiation and gene pool history of East European populations.  相似文献   

9.
Abstract. The woody and shrubby riparian vegetation of the Mediterranean Region of Spain shows a progressive displacement from the Querco-Fagetea, typical of Central Europe, towards the Nerio-Tamaricetea, which has its maximum expression in North Africa. We studied the occurrence of 107 riparian plant communities on 52 locations in the Segura River Basin (SE Spain) and their presumed relation to variation in rainfall and temperature. On the basis of agglomerative clustering and Redundancy Analysis (RDA) three riparian vegetation complexes were identified and characterized by (a) Central European-related temperate communities, (b) predominantly North African riparian communities and (c) a combination of both community types, respectively. North African communities predominated in the lower stretches of the Segura Basin, probably due to the prevailing semi-arid bioclimate.  相似文献   

10.
Nucleotide sequences of the mitochondrial DNA (mtDNA) control region were studied in Germans living in the Altai, Russia. Although this ethnic group has been living in Russia for a long time, the obtained data indicate that its mitochondrial gene pool retains the main characteristics of the Western and Central European gene pools. Regarding the mitochondrial gene pool, Russian Germans were more similar to Germans living in Germany than to Russians with regard to the frequency of the Cambridge nucleotide sequence, frequencies and composition of five European haplotypic groups (classification of Richards et al.), and average intra- and interpopulation pairwise nucleotide differences. However, the mitochondrial gene pool of Altaian Germans also differed from that of Western European populations. The gene pool of Altaian Germans contained the ancestral variants of the main haplotypic groups. To date, these variants have not been found in modern Western and Central European populations, which is apparently due to their lower frequencies. In addition, some previously unknown mtDNA variants with specific nucleotide substitutions were found in Altaian Germans. The obtained results suggest that the modern mitochondrial gene pool of Europeans, including Germans from Germany, was largely affected by the demographic processes that occurred in the past two centuries. The Germans that lived in Russia were relatively isolated and, hence, retained more characteristics of the ancestral gene pool.  相似文献   

11.
A complete taxonomic review of Neogene birds of continental Asia is provided. To date, avifauna from the latter half of the Miocene and Pliocene of Central Asia (Mongolia and adjacent regions of Inner Asia) are most thoroughly investigated. Available data enable a reconstruction of successive replacement of Early and Middle Miocene avifaunas by communities of the Recent type. Middle Miocene avifaunas of Mongolia include a great number of extinct genera and species, many of which were widespread in Eurasia. Extant genera became dominant in the Late Miocene and taxa close to living species appear in the Late Pliocene fossil record. Late Pliocene communities of birds of Central Asia were complex in genesis, composed of Miocene relicts (Struthio), immigrants from the European regions of the Palearctic (phasianid Plioperdix), North American immigrants (Calcarius), and also autochthonous elements, the origin of which is apparently connected with the arid belt of Central Asia (diverse passerines).  相似文献   

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Focusing on each country’s topmost destination/origin migration relation with other countries, this study builds top1 destination networks and top1 origin networks in order to understand their skeletal construction and community dynamics. Each top1 network covers approximately 50% of the complete migrant network stock for each decade between 1960 and 2000. We investigate the community structure by implementing the Girvan-Newman algorithm and compare the number of components and communities to illustrate their differences. We find that (i) both top1 networks (origin and destination) exhibited communities with a clear structure and a surprising evolution, although 80% edges persist between each decade; (ii) top1 destination networks focused on developed countries exhibiting shorter paths and preferring more advance countries, while top1 origin networks focused both on developed as well as more substantial developing nations that presented a longer path and more stable groups; (iii) only few countries have a decisive influence on community evolution of both top1 networks. USA took the leading position as a destination country in top1 destination networks, while China and India were the main Asian emigration countries in top1 origin networks; European countries and the Russian Federation played an important role in both.  相似文献   

14.
The gene pool formation of the modern domestic breeds of pig Sus scrofa domestica and their genesis based on hybridization of wild ancestral forms of the European and Asian origin were studied using molecular immunogenetic methods. Males of the European and Central Asian S. scrofa subspecies (S. s. scrofa and S. s. nigripes were hybridized with domestic pigs of the Swedish Landrace and Vietnamese Black Masked breeds. In addition, we examined the genotypic structure of 65 wild, aboriginal, and local populations as well as cultured breeds, including the stock breeds with different levels of selection. Frequencies of alleles and suballelles of the chromosome 4 locus controlling antigens of the L blood group system were analyzed. The origin of marker suballeles of the European and Asian origin was estimated in the most widespread world pig breeds. Unexpectedly, a strikingly high frequency of the Asian elements was found in the most productive European and American breeds, as well as in the best breeds of Russia and other CIS countries. Only one form of heterozygosity (bcgi/bdfi) was found in a population of wild European ancestors, whereas domestic pig breeds displayed heterozygosity for far more numerous suballeles of the locus studied. Animals with heterozygosity for alleles of the European and Asian origin showed higher adaptivity and fertility.__________Translated from Genetika, Vol. 41, No. 4, 2005, pp. 566–576.Original Russian Text Copyright © 2005 by Tikhonov.  相似文献   

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Abstract. Up to now the syntaxonomy of the Fagus woods of the southern Balkans is far less known than that of beech communities in the northwestern part of the Balkan Peninsula and in central and western Europe. A set of 607 phytosociological relevés from southeastern Serbia, the Former Yugoslav Republic of Macedonia, and northern and central Greece was subjected to numerical classification and ordination. These results were used for a syntaxonomic revision of Fagus, Fagus‐Abies and Fagus‐Acer woodland communities of the southwestern Balkans. The Doronico columnae‐Fagenion (seven associations from Serbia, the F.Y.R.O.M., and high altitudes in northern Greece) and the Doronico orientalis‐Fagenion (four associations from northern and central Greece) were distinguished. The results of ordination by Canonical Variates Analysis (CVA) showed a very distinct phytogeographical pattern of differentiation between community types. The floristic composition of Fagus woods changes markedly along the north‐south gradient. The share of Subbalkan, Balkan, Submediterranean and Mediterranean species increases significantly towards the south, while the Central‐European, European, Euro‐Siberian, Euro‐Asiatic and Circumpolar species decrease in the same direction. The syntaxonomic differentiation of the Fagus woodlands and their classification into regional suballiances reflects this gradient. With the rise in altitude, the number of Balkan, Mediterranean, Submediterranean, European and Euro‐Asiatic species declines.  相似文献   

17.
《Plains anthropologist》2013,58(69):187-196
Abstract

Beginning in the 1880s, chain mail fragments have been found subsurface at five archeological sites in the Central Plains. All were in association with native Indian materials assignable to the Great Bend aspect and datable to the earliest period of European contacts with Central Plains Village Indian communities in the mid-sixteenth century. Among the several types of mail fabric represented, none is inconsistent with a 16th century Spanish provenience. Possible sources from which these items may have reached the Indians by pillage, theft, or trade are considered.  相似文献   

18.
Long-term dynamics of small mammal communities are perennial themes in population ecology. However, comprehensive studies on the effect of environmental factors on population dynamics are still rare. Here, we aimed to analyze long-term data on Central European communities of small mammals occurring in two habitats that greatly differed in their structure, successional stages, and forest management. We found a richer community structure in young spruce plantations compared to mature European beech forests. In young spruce plantations, Myodes glareolus and Apodemus flavicollis abundances increased and Sorex araneus abundances decreased during the study period as a result of forest growth and management. Community structure in mature beech forests did not change significantly during the study period. Apodemus flavicollis and Myodes glareolus showed 3- and 5-year population cycles, respectively, and their abundances were simultaneously positively correlated with relative abundance of masts. Weather also played a role, while the effect of snow cover was pronounced only in mountain areas where it negatively affected Microtus agrestis and Sorex araneus abundances, temperature positively and rainfall negatively influenced Myodes glareolus and Apodemus flavicollis abundances across both studied habitats. Our findings document that a complex of environmental factors significantly affects the structure and dynamics of small mammal communities in Central Europe, and both local biotic and abiotic factors should be considered in future studies.  相似文献   

19.
Recent studies of mammal faunas from the Vienna and Pannonian Basins—in particular the assemblage from Kohfidisch in Burgenland (Austria)—provide new data on the faunal turnover at the Vallesian—Turolian transition. They demonstrated a considerable influence of the faunal exchanges between Greco-Iranian, Eastern European and Central European faunal provinces on renewal of mammal communities in Central Europe, particularly at MN10/MN11 boundary around 8.7 Ma. Five new comers from the Balkano-Iranian region (Gazella aff. pigrimi, ?Nisidorcas, Tragoportax gaudryi, Protoryx and Palaeoryx) coexisted in the Early Turolian of Central Europe with the Middle Miocene autochthonous (Orygotherium, Dorcatherium naui, Micromeryx, Euprox, Amphiprox anocerus and Miotragocerus pannoniae) and Late Miocene invaders from Eastern Europe (Procapreolus and Cervavitus). Dispersal events were close related to palaeoenvironmental and climatic changes.  相似文献   

20.
Theoretical basis of ecologo-floristic classification according to Braun-Blanquet approach is discussed with the special attention to the contribution of Russian scientists. Principal results concern presentation of vegetation continuum in discrete classification units: polymodal conception of plant communities, principle of plural syntaxonomic decisions, pragmatic approach to classification, method of homological rows of plant communities, etc. Current ecologo-floristic classification of vegetation in Russia consists of 77 classes. This system is a good basement for estimation of rarity of plant communities and biodiversity protection. The first variant of "Red Book" of plant communities of Russia and other eastern European countries is discussed.  相似文献   

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