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1.
This paper considers the features of the ecology and annual cycle of the arctic warbler in the northern part of Western Siberia, which migrates to wintering places to the southeast in Indo-China, in comparison with the ecology of the willow warbler, which migrates to the southwest to Africa. The influence of the length of the migratory path and the ecological conditions of flight on the nesting ecology of the arctic warbler and the possibilities of advancement of the species to the tundra area of the Yamal Peninsula is analyzed.  相似文献   

2.
Arctic driftwood represents a unique proxy archive at the interface of marine and terrestrial environments. Combined wood anatomical and dendrochronological analyses have been used to detect the origin of driftwood and may allow past timber floating activities, as well as past sea ice and ocean current dynamics to be reconstructed. However, the success of driftwood provenancing studies depends on the length, number, and quality of circumpolar boreal reference chronologies. Here, we introduce a Eurasian-wide high-latitude network of 286 ring width chronologies from the International Tree Ring Data Bank (ITRDB) and 160 additional sites comprising the three main boreal conifers Pinus, Larix, and Picea. We assess the correlation structure within the network to identify growth patterns in the catchment areas of large Eurasian rivers, the main driftwood deliverers. The occurrence of common growth patterns between and differing patterns within catchments indicates the importance of biogeographic zones for ring width formation and emphasizes the degree of spatial precision when provenancing. Reference chronologies covering millennial timescales are so far restricted to a few larch sites in Central and Eastern Siberia (eastern Taimyr, Yamal Peninsula and north-eastern Yakutia), as well as several pine sites in Scandinavia, where large rivers are missing though. The general good spatial coverage of tree-ring sites across northern Eurasia indicates the need for updating and extending existing chronologies rather than developing new sites.  相似文献   

3.
Most of the dendrochronological efforts in northern Patagonia have been invested in long-lived conifer species, whereas several broadleaf species have received less attention. This is the case for Nothofagus dombeyi, a dominant species in the mesic temperate and rainforests in the region. The aim of this study was to develop the first tree-ring chronologies for N. dombeyi in northern Patagonian and contribute to the future dendroecological and dendroclimatological studies in the region. Using standard dendrochronological techniques, six tree-ring-width chronologies were obtained encompassing the east–west precipitation gradient of this species in the Argentinean sector of the northern Patagonian Andes. Chronology statistics indicated that N. dombeyi records are highly reliable and a good source of information on tree-growth variability in the region. Stands located in the xeric sectors of the gradient showed higher inter-site variability. Also, results presented here showed that N. dombeyi has a large potential for the study of climatic variability in northern Patagonia.  相似文献   

4.
Across Britain and continental Europe there are many ancient Castanea sativa trees of great significance for natural and cultural heritage, yet scant assessment has been made of them for dendrochronological information. This paper describes the dendrochronological analysis of 28 Castanea sativa trees (veteran historic trees, forest trees and coppice stems) sampled from 15 sites in southern Britain: 56 growth-ring sequences were collected for analysis, by boring living trees and by cutting transverse sections from dead fallen trees and previously cut stumps. Twenty-three single-tree sequences from 14 sites were cross-matched (t ≥3.5) and then cross-dated with 17 oak Quercus reference chronologies from England and northern France: a Castanea sativa master chronology spanning AD 1660–2014 has been created. The results demonstrate the viability of dendrochronological analysis of Castanea sativa wood; and confirm that Castanea sativa can be cross-dated with oak Quercus reference chronologies, inter-regionally and inter-nationally. The findings provide the potential means for dating Castanea sativa timbers sampled from palaeoenvironmental and historical contexts. The extraction of sawn sections from long-dead (up to 60 years in this study) trees and stumps is proven to be a reliable method for dating veteran trees in cultural landscapes and ancient woodlands; and for revealing the growth history of historic/iconic trees. The germination dates calculated for the Castanea sativa trees in this study span the period AD 1640–1943. The inaccuracy of estimating veteran Castanea sativa tree ages from girth measurements is highlighted.  相似文献   

5.
Reconstruction of the dynamics of the range of Artemisia genus was carried out with the help of palynoareological method on the basis of the data of 97 pollen diagrams from the territory of Western Siberia and the Altai-Sayan mountainous region over the millennial time sections since the Late Glacial time till the present time. It was revealed that the maximal spread of the Artemisia steppe communities (probably of the cryoarid pattern) occurred at the territory under examination at 13–10 ka yr BP. After the time point of 9 ka yr BP a fundamental change in landscapes of Western Siberia occurred which resulted in the disintegration of previously continuous Artemisia steppe cover into separate blocks. Since 8 ka yr BP the Artemisia steppe communities of modern appearance occupied the zones of modern steppe and forest-steppe of Western Siberia and Northern Kazakhstan while over the taiga zone the Artemisia plant communities were spread occasionally under the extra zonal conditions and as the pioneering plant groupings on naturally disturbed soils. Since the time point of 4 ka yr BP till the present time the northern boundary of the steppe zone under-went pulsing shifts to the north and back and also broadening and narrowing of isolated insular steppes in Altai-Sayan mountain region took place. At present time we observe an increase in the role of plants of Artemisia genus in the tundra zone of Western Siberia and in the Altai mountains.  相似文献   

6.
The mitochondrial DNA of modern Native Americans has been shown to fall into one of at least five haplogroups (A, B, C, D, or X) whose frequencies differ among tribal groups. The frequencies of these five haplogroups in a collection of ancient individuals from Western Nevada dating to between approximately 350-9,200 years BP were determined. These data were used to test the hypothesis, supported by archaeological and linguistic data, that the current inhabitants of the Great Basin, the Numic speakers, are recent immigrants into the area who replaced the previous non-Numic inhabitants. The frequency distributions of haplogroups in the ancient and modern Native Americans differed significantly, suggesting that there is a genetic discontinuity between the ancient inhabitants and the modern Numic speakers, providing further support for the Recent Numic Expansion hypothesis. The distribution of mitochondrial haplogroups of the ancient inhabitants of the Great Basin is most similar to those of some of the modern Native American inhabitants of California.  相似文献   

7.
We present a paleoparasitological analysis of the medieval Zeleniy Yar burial ground of the XII-XII centuries AD located in the northern part of Western Siberia. Parasite eggs, identified as eggs of Opisthorchis felineus, were found in the samples from the pelvic area of a one year old infant buried at the site. Presence of these eggs in the soil samples from the infant’s abdomen suggests that he/she was infected with opisthorchiasis and imply consumption of undercooked fish. Ethnographic records collected among the population of the northern part of Western Siberia reveal numerous cases of feeding raw fish to their children. Zeleniy Yar case of opisthorchiasis suggests that this dietary custom has persisted from at least medieval times.  相似文献   

8.
Throughout the Middle Ages forests in Flanders (northern Belgium) experienced a dramatic human influence. Forests were logged for wood supply and converted to arable land. The structure of the remaining forests was altered. This, combined with the tempering influence of the Atlantic climate, results in conditions that are suboptimal for dendrochronological research. Tree-ring series of Quercus robur and Q. petraea of timber from medieval archaeological sites are often short, show abrupt growth-rate variations and are complacent. The question arises whether tree-ring series of this type are potential records of past management and whether they could constitute the basis of a reference chronology for archaeological dating. During six archaeological excavations in and around the medieval town of Ypres, cross-sections were collected. The tree-ring series could be dated back to the 12th–14th centuries, using reference chronologies from surrounding regions. The growth pattern of the short sequences displays a high similarity to tree-ring series from modern coppice. For the first time, it has been confirmed that dendrochronological analysis in Flanders is possible and can provide valuable information on medieval forest use and structure.  相似文献   

9.
North China and South Siberia, populated by Altaic- and Sino-Tibetan-speaking populations, possess extensive ethnolinguistic diversity and serve as the crossroads for the initial peopling of America and western–eastern transcontinental communication. However, the population genetic structure and admixture history of northern East Asians remain poorly understood due to a lack of genome-wide data, especially for Mongolic-speaking people in China. We genotyped genome-wide single nucleotide polymorphisms for 510 individuals from 38 Mongolic, Tungusic, and Sinitic-speaking populations. We first explored the shared alleles and haplotypes within the studied groups. We then merged with 3508 published modern and ancient Eurasian individuals to reconstruct the deep evolutionary and natural selection history of northern East Asians. We identified genetic substructures within Altaic-speaking populations: Western Turkic people harbored more western Eurasian-related ancestry; Northern Mongolic people in Siberia and eastern Tungusic people in Amur River Basin (ARB) possessed a majority of Neolithic ARB related ancestry; Southern Mongolic people in China possessed apparent genetic influence from Neolithic Yellow River Basin (YRB) farmers. Additionally, we found the differentiated admixture history between western and eastern Mongolians and geographically close Northeast Hans: the former received a genetic impact from western Eurasians, and the latter retained the primary Neolithic YRB and ARB ancestry. Moreover, we demonstrated that Kalmyk people from the northern Caucasus Mountains possessed a strong genetic affinity with Neolithic Mongolian Plateau (MP) people, supporting the hypothesis of their eastern Eurasian origin and long-distance migration history. We also illuminated that historical pastoral empires in the MP contributed considerably to the gene pool of northern Mongolic people but rarely to the southern ones. We finally found natural selection signatures in Mongolians associated with alcohol metabolism. Our results demonstrated that the Neolithic ancestral sources from the MP or ARB played an important role in spreading Altaic populations and languages. The observed multisources of genetic diversity contributed significantly to the extensive ethnolinguistic diversity in northern East Asia.  相似文献   

10.
Tree rings of 184 archaeological wood samples from two Late Bronze to early Iron Age lake sites at Lake Luokesa (Luokesai e?eras), Lithuania, Moletai district, were analyzed. Despite severe difficulties with synchronization, Pinus (pine), Quercus (oak) and Alnus (alder) yielded some cross-datable series. The general picture is that the settlers chose small trees as timber, which they used in their natural round shape. The trees did not grow in homogeneous even-aged stands, but show very different ages and growth levels. Despite the generally low numbers of tree rings in the individual samples, the strong archaeological framework allowed cross-dating of some series and the building of chronologies for single structures. Based on these attempts, a 90 year long first floating chronology of the settlement structures is presented. Luokesa Site 2 (L2) was mainly built within the relative year 53. Luokesa Site 1 (L1) was certainly in use from the relative year 74 onwards. All fences at L1 show their main building activity in the relative year 81, four years after the main building activities in the village itself. It can be concluded that the settlement L1 was in use for at least 16 years. Because of the lack of a standard dendrochronological curve for the Baltic region, wiggle-matching was applied to obtain an absolute date for both settlements. The data clearly show that all samples relate to the Late Bronze–early Iron Age. The period where all wiggle matching results overlap is the period between 625 and 535 bc (the 2σ ranges are given). Based on the dating, duration and timber characteristics of the occupation, comparisons with Polish early Iron Age sites are made, which indicate a close resemblance in terms of wood use and settlement concept.  相似文献   

11.
In ancient Samoa,Cordyline roots were prepared for use as a candy and a sweetening agent by baking in large buried stone ovens for several days. In a modern attempt to duplicate this ancient technology,Cordyline terminalis roots collected in the mountains of Upolu, Western Samoa, were baked in both a modern propane oven and in an oven orumu prepared in the traditional manner. The success of this attempt is described, together with its significance for ethnobotanical and archaeological studies in Samoa.  相似文献   

12.
Professor Dumond's research on the Alaska Peninsula provided information that prior to 1,000 years ago people of both sides of the Alaska Peninsula shared material culture and exhibited subsistence interests that persisted into historic times, During the Late Precontact Era (ca. 1100 A.D. to mid-1700s) these Alutiiq societies shared cultural traits including language, house styles, and material culture with their relatives and neighbors on Kodiak Island. Until recently, few data were available regarding potential variability in house construction techniques, or styles and functions of Alutiiq semi-subterranean houses of this era found on the Alaska Peninsula, This paper provides examples of a few known prehistoric and historic Alaska Peninsula and Kodiak Alutiiq houses and presents previously unreported data from archaeological tests at Marraatuq on the Central Alaska Peninsula, Taken together with Dumond's 1998-1999 field work at Leader Creek and archaeological research on Kodiak Island, the work provides further evidence that interregional interaction was strong during the Late Precontact Era. However, large population centers and ranked political hierarchies probably were not hallmarks of central Alaska Peninsula communities during the Late Precontact Era and historic times as they were on the Kodiak and Aleutian islands.  相似文献   

13.
The concept of typological variability of physiological individuality was a methodological basis for chrono-physiological assessment of habitual physical activity (HPA) and heart rate (HR) in individuals with different functional types of constitution (FTC) (low HPA (FTC-1), medium HPA (FTC-2), and high HPA (FTC-3)) living at different latitudes of West Siberia (Tyumen, 57°09’N; Khanty–Mansi Autonomous Okrug (KhMAO)–Yugra, 61°00’N; and Yamal–Nenets Autonomous Okrug (YaNAO), 63°12’N). The typical chronostructure of the circadian rhythm of HPA and HR was established for each FTC under the conditions of both mid-latitude (Tyumen) and northern regions. The regional differences were determined too. Compared to the mid-latitude parameters, the chrono-physiological assessment of typological variability of HPA and HR in FTC-1, FTC-2 and FTC-3 subjects living under the climatic and geographical conditions of KhMAO–Yugra and YaNAO in each respective group demonstrated a decrease in the midline-estimating statistic of rhythm (MESOR) and energy intensity of the circadian rhythm, an increase in the proportion of ultradian rhythms, differences in the time of HPA and HR acrophases, a decrease in synchronization and coherence indices, as well as a higher coefficient of the number of heart beats per locomotion and a lower circadian index. All of the above parameters of northerners with each FTC, with regard for the general principles of modern approaches, are not pathologies but rather regional characteristics that should be taken into consideration in the assessment of general state of health and prenosological diagnostics; they were the basis for using chronoprevention and time correction of reduced physical activity.  相似文献   

14.
Genetic variation has been studied in 32 Eastern Siberian and Far Eastern populations of Larix Mill. with the use of three mitochondrial markers based on polymerase chain reaction. Eight multilocus haplotypes with a heterogeneous spatial distribution (G ST = 0.788, N ST = 0.829) have been found, which indicates limited gene flows between populations. Several geographic regions with specific larch haplotype sets have been determined: (1) Japan, (2) southern Sakhalin and the Kuril Islands, (3) Primor’e and Korea, (4) Kamchatka, and (5) Eastern Siberia and the northern Far East. The haplotype fixed in the Kamchatka is absent in the Magadan oblast or Chukotka but is present in southern Primor’e and Sakhalin Island. This may be explained by either the postglacial recolonization of Kamchatka by larch that spread from Primor’e through Sakhalin and the Kuril Islands or its survival through the last glacial maximum in the Kamchatka Peninsula. The biogeography of larch and other woody plants indicate that boreal species have a common history of the colonization of Kamchatka.  相似文献   

15.
The Ficoncella site in northern Latium (Italy) represents a unique opportunity to investigate the modalities of a short occupation in an alluvial setting during the Lower Palaeolithic. The small excavation area yielded a lithic assemblage, a carcass of Palaeoloxodon antiquus, and some other faunal remains. The main objectives of the study are to better characterize the depositional context where the Palaeoloxodon and the lithic assemblage occur, and to evaluate with greater precision the occupation dynamics. A 25 m-long well was drilled just above the top of the terrace of the Ficoncella site and faunal and lithic remains were analyzed with current and innovative techniques. The archaeological site contains floodplain deposits as it is located next to a small incised valley that feeds into a larger valley of the Mignone River. A tephra layer capping the site is 40Ar/39Ar dated to 441± 8 ka. Collectively, the geochronologic, tephrochronologic and geologic data, suggest the site was occupied during MIS 13. The new results should prompt further research at Ficoncella in order to improve our understanding of the dynamics of human settlement in Europe during the Early to Middle Pleistocene.  相似文献   

16.
我国新疆地区自古以来即是东西方文明相互交融的摇篮,以往的考古学、体质人类学研究表明,该区域内不同文化之间的互通有无早在我国青铜-早期铁器时代便已经发生。关于这种交流与融合产生的原因,目前学术界仍未有定论。新疆于田流水墓地(2950±50 BP)是由中国社会科学院考古研究所于2003-2005年主持发掘的青铜时代墓葬群,该墓地共发掘墓葬65座,被视为是昆仑山北麓发现的最早人类文化遗存。本文从采集自流水墓地108例人骨标本的19项牙齿非测量性状研究入手,将其与欧亚大陆范围内的古今人群进行比较研究,并进行史密斯生物学距离的计算以及主成分分析。结果表明:生活在新疆流水地区的古代人类与南西伯利亚地区、日本绳纹、阿富汗/巴基斯坦、中国姜家梁地区人群之间在牙齿非测量性状方面存在某种程度上的相似性,这或许可以说明至少在3000年前,我国新疆西南部地区可能已经存在了东西方的人群迁徙。  相似文献   

17.
This paper is devoted to an analysis of the pattern of zonal distribution of mesofaunal arthropods, birds, and vascular plants in the area from northern taiga forests to arctic tunrdas of the Yamal Peninsula by the gradient of summer air temperatures. The latitudinal dynamics of northern ecosystems determines differences in the number of plant species that have a direct effect on the species richness and abundance of invertebrates and an indirect one through invertebrates on the same indices of birds. Breaks in continuity marking the natural boundaries where the components of arctic communities become boreal have been found in the changes of species diversity.  相似文献   

18.
Detailed palynological analysis of glacial, tectonic, and crater lakes of northeastern Siberia reveals continuous records of the changing vegetation during one or several climatic cycles of the Pleistocene and in the Holocene. The most continuous records in the mountain areas of the region are those of Lake Elikchan-4 (northern Okhotsk Sea Region). Pollen records of Lake El’gygytgyn, which was formed by the impact of a meteorite in the northern Chukchi Peninsula, reflect the response of land vegetation to the global climatic impact during the last 300 ka.  相似文献   

19.
The Yakuts (also known as Sakha), Turkic-speaking cattle- and horse-breeders, inhabit a vast territory in Central and northeastern Siberia. On the basis of the archaeological, ethnographic and linguistic evidence, they are assumed to have migrated north from their original area of settlement in the vicinity of Lake Baykal in South Siberia under the pressure of the Mongol expansion during the thirteenth to fifteenth century AD: . During their initial migration and subsequent expansion, the ancestors of the Yakuts settled in the territory originally occupied by Tungusic- and Uralic-speaking reindeer-herders and hunters. In this paper we use mtDNA and Y-chromosomal analyses to elucidate whether the Yakut immigration and expansion was accompanied by admixture with the indigenous populations of their new area of settlement or whether the Yakuts displaced the original inhabitants without intermarriage. The mtDNA results show a very close affinity of the Yakuts with Central Asian and South Siberian groups, which confirms their southern origin. There is no conclusive evidence for admixture with indigenous populations, though a small amount cannot be excluded on the basis of the mtDNA data alone. The Y-chromosomal results confirm previous findings of a very strong bottleneck in the Yakuts, the age of which is in good accordance with the hypothesis that the Yakuts migrated north under Mongol pressure. Furthermore, the genetic results show that the Yakuts are a very homogenous population, notwithstanding their current spread over a very large territory. This confirms the historical accounts that they spread over their current area of settlement fairly recently.  相似文献   

20.
A palaeoecological study was conducted close to the forest limit in the northern Scandinavian mountain range. The aim was to elucidate the degree to which human impact has affected the vegetation at Hiednikvalta, a Stállo settlement site. Stállo settlements consist of round hut foundations that have a hearth in the middle and are surrounded by a low turf wall. They were probably established by Sámi people using the mountain areas for hunting and/or reindeer herding. In order to separate the effects of humans and climate on the vegetation, a reference area approach was adopted, i.e. the vegetation development at the Stállo settlement site Hiednikvalta was compared with the vegetation development in a forested reference area Avvuhatjåhkkå, at the same altitude as Hiednikvalta but with no archaeological remains of settlements. Peat stratigraphies were retrieved at the two sites and pollen analysis, loss-on-ignition (LOI), pollen accumulation rates (PAR), macrofossil analysis and Betula pollen size statistics were all examined. The results indicate that Hiednikvalta was forested with Betula trees prior to the Stállo settlement period, which occurred between the eighth and thirteenth centuries. Human activities resulted in a decrease in tree cover at the site, as found in a previous study at Adamvalta, another Stállo settlement site in the region. However, the magnitude of vegetation change, and the post-Stállo vegetation development differed between the two areas, suggesting that site-specific factors are important. The use of reference areas in palynological studies is also discussed.  相似文献   

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