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【目的】黄土-古土壤序列是记录第四纪气候环境变化的良好载体,其内部的土壤微生物特征是蕴含土壤环境变化的重要信息。由于黄土与古土壤成壤环境的气候差异,微生物群落结构特征可能会有不同的响应,但针对该问题的研究还十分有限。【方法】选择任家坡(R)和九州台(J)两地黄土(RL和JL)-古土壤(RS和JS)序列,运用高通量测序技术和线性判别分析效应大小(linear discriminant analysis effect size, LEfSe)识别土壤原核生物群落结构和类群差异,基于原核生物分类单元功能注释(functional annotation of prokaryotic taxa, FAPROTAX)数据库进行群落功能预测,以及利用Mantel test探讨影响土壤原核生物群落稳定的环境因子。【结果】土壤中碳氮营养物质与气候变化的代用指标磁化率、Rb/Sr变化趋势一致,含量整体表现为古土壤(RS和JS)高,对应的黄土(RL和JL)低,这一特征在任家坡古土壤(RS)中尤为显著;在同一气候时期,九州台较任家坡更为干冷,并且九州台古土壤沉积阶段也受到较强冬季风的影响,使其气候冷干与暖湿转变呈渐变型。原核生物群落结构中酸杆菌门(Acidobacteria)、泉古菌门(Crenarchaeota)、绿弯菌门(Chloroflexi)等具有嗜热嗜温性质的细菌和古菌在任家坡黄土-古土壤(RL和RS)中丰度较高,芽单胞菌门(Gemmatimonadetes)、放线菌门(Actinobacteria)、厚壁菌门(Firmicutes)、广古菌门(Euryarchaeota)、异常球菌-栖热菌门(Deinococcus-Thermus)等耐旱、适宜极端环境中生存的细菌和古菌在九州台黄土-古土壤中(JL和JS)丰度较高。同时,生命产能、氮、锰、铁、氯元素循环相关功能基因在任家坡古土壤(RS)中表达量最高,而碳、氢、硫元素循环相关功能基因在任家坡黄土(RL)中表达量最高。与任家坡相比,九州台原核生物群落具有物种多样性高、功能种类少的特点。Mantel test分析进一步表明,有机碳(soil organic carbon,SOC)、含水率(soil water content,SWC)、总氮(total nitrogen,TN)和硝态氮(nitrate nitrogen,NO3--N)是影响任家坡原核生物群落和功能稳定的关键环境因子,而TN、SOC、pH值和铵态氮(NH4+-N)是影响九州台原核生物群落和功能稳定的关键环境因子。【结论】在暖湿期,微生物群落分化出更多的功能种类,具有更旺盛的生命活动;在冷干期,微生物群落通过提高物种多样性来完成主要的生命活动功能,通过协同共生维持群落生存和稳定来适应环境胁迫。研究成果对认识气候变化对土壤微生物多样性和功能的影响具有重要意义。 相似文献
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东北二龙湾玛珥湖晚更新世晚期植被与环境变化的孢粉记录 总被引:2,自引:0,他引:2
东北二龙湾玛珥湖孢粉记录显示,34 ka B.P.以来,该区植被和气候经历了以下变化:34-29.3 ka B.P.,发育山地寒温性针叶林,气候冷湿.29.3-12.6 ka B.P.,该区以寒温性针叶林、桦树林为主,气候转向冷干发展,尤其在20.6-18.7 ka B.P.(LGM)时,表现最为突出.12.6-8.9 ka B.P.,该区植被为针阔叶混交林,气候由冷干向温湿逐渐过渡,8.9-4.6 ka B.P.,为落叶阔叶林,气候温暖湿润.4.6 ka B.P.至今,发育针阔叶混交林,气候向温凉转干方向发展.研究表明,MIS3a阶段,以二龙湾为代表的中国东北东部气候以冷湿为主要特征,而末次冰期对该区的影响直到12.6 ka B.P.以后才结束. 相似文献
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我国早、中更新世古人类和旧石器遗址蕴含着丰富的早期人类活动和生存环境的背景信息,建立精确的遗址年代序列是分析古人类活动的基础。近二十年来,旧石器时代考古和测年研究为建立我国早期人类活动的年代框架提供了丰富的材料。本文分析了目前我国已发表的95个有独立测年数据的早、中更新世遗址,将其纳入黄土-古土壤年代框架,初步建立自200多万年至末次间冰期的古人类活动年代序列,根据它们的时空分布,进一步阐释了古人类在不同区域活动强度演变的时空特征。总体来看,这些遗址在泥河湾-周口店、秦岭山地、长江下游及长江流域以南(南方)四大区域呈现出聚集分布的特征;区域古人类活动强度主要表现在从早更新世的泥河湾-周口店、中更新世的秦岭山地、到中更新世晚期的长江中下游和南方区域的时空序列上。此外,仍有较多已发掘遗址缺少年代研究或存在测年问题,今后需要加强遗址的精确测年研究。 相似文献
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CAJUS G. DIEDRICH 《Zoological Journal of the Linnean Society》2008,154(4):822-831
The rediscovered holotype skulls of Late Pleistocene Panthera leo spelaea ( Goldfuss, 1810 ) (Felidae) and Crocuta crocuta spelaea ( Goldfuss, 1823 ) (Hyaenidae) from the Zoolithen Cave at Burggeilenreuth, southern Germany, are discussed. The cave became famous mainly due to its rich cave bear bone remains from the late Saalian (OIS 6–8) to Eemian/Weichselian (OIS 3–6) including additionally a third holotype of Ursus spelaeus Rosenmüller, 1794 (Ursidae). The ‘Felis spelaea’ holotype represents an adult male with a strong bite mark on the saggital crest, which was in an early stage of healing. Compared with other European Late Pleistocene lion skulls and skeletons, and with modern African lions, it provides evidence of intraspecific conflict between male Ice Age lions. The holotype of ‘Hyaena spelaea’ is one of several hundred hyena remains from a well‐frequented hyena den cave. The cave was used intensively by Late Pleistocene hyena clans, for collecting lion carcasses in addition to their accustomed prey, as happened in many caves throughout Europe. Ice Age spotted hyena clans might have killed Ice Age steppe lions for many reasons, such as fights over prey and territory, and the protection of cubs, but they did not always scavenge on their carcasses. © 2008 The Linnean Society of London, Zoological Journal of the Linnean Society, 2008, 154 , 822–831. 相似文献
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Behavioral modernity is considered one of the defining characteristics separating modern humans from earlier hominin lineages. Over the course of the past two decades, the nature and origins of modern human behavior have been among the most debated topics in paleoanthropology. 1 - 7 There are currently two primary competing hypotheses regarding how and when modern human behavior arose. The first one, which we shall term the saltational model, argues that between 50–40 kya modern human behavior appeared suddenly and as a “package”; that is, the entire range of traits appeared more or less simultaneously. The proposed reason most often cited for this sudden change in behavior is a genetic mutation, possibly related to communication, 7 that occurred around 50 kya. The second major hypothesis, which we shall term the gradualistic model, argues that modern human behavior arose slowly and sporadically over the course of the past 150,000 years and may be related to increasing population pressure. 2 In general, many European scholars subscribe to the saltational model, while many Africanists seem to prefer the gradualistic model. As McBrearty and Brooks 2 noted, the disagreement may be related to different developmental histories underlying the research traditions in Europe and Africa. 相似文献
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Michael J. Walker A. Vincent Lombardi Josefina Zapata Erik Trinkaus 《American journal of physical anthropology》2010,142(2):261-272
The Middle Paleolithic levels of the Sima de las Palomas have yielded eight partial mandibles (Palomas 1, 6, 7, 23, 49, 59, 80, and 88). Palomas 7, 49, 80, and 88 are immature, and Palomas 49, 59, 80, and 88 are among the latest Neandertals (~40,000 cal BP). Palomas 1 is geologically older (~50,000–60,000 cal BP), and the other three were found ex situ. The mandibles exhibit a suite of characteristics that align them with the Neandertals among later Pleistocene humans, including symphyseal morphology, symphyseal orientation, corpus robusticity, distal mental foramen position, retromolar space presence, wide immature dental arcade, and high‐coronoid process with an asymmetrical mandibular notch. However, Palomas 6 lacks a retromolar space, Palomas 59 has a narrow lateral corpus, and Palomas 80 has a mesial mental foramen and open mandibular foramen. The Palomas mandibles therefore help to document that the late Middle Paleolithic of southern Iberia was the product of Neandertals. They also reinforce the presence of variability in both metric and discrete aspects of Neandertal mandibular morphology, both within and across samples, some of which may be temporal and/or geographic in nature. Am J Phys Anthropol, 2010. © 2009 Wiley‐Liss, Inc. 相似文献
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M F Skinner 《American journal of physical anthropology》1986,69(1):59-69
A roughly circular hypoplastic defect restricted to the labial enamel surface of the deciduous canine is described. This pathology is quite common in available samples of Upper Paleolithic and Neolithic children and a cadaver sample of recent Calcuttans, affecting 44% to 70% of individuals. It is rare in a Neanderthal sample and in children from a clinical practice in Vancouver. The lesion occurs twice as commonly in the lower jaw. The defect appears to commence at or after birth owing to localized pressure on thin or nonexistent alveolar bone overlying the bulging crypt of the deciduous canine. Population differences in the incidence of the pathology probably reflect innate and acquired variation in hard and soft tissue thicknesses in this region. 相似文献
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Early excavations at the Willendorf site complex in Austria yielded a femoral diaphysis collected between 1883 and 1887 and a mandibular symphysis discovered in 1908--1909. The femoral section, Willendorf 1, derives from the Willendorf I site and direct AMS (14)C dating (24,250+/-180 years B.P.) assigns it to layer 9. The Willendorf 2 mandibular piece was excavated from layer 9 of the Willendorf II site, which is AMS (14)C dated to 24,000--23,900 years B.P. The Willendorf 1 femoral piece is relatively small and exhibits a pronounced pilaster and linear aspera, moderately elevated relative cortical area, and a level of diaphyseal robusticity in the middle of the European earlier Upper Paleolithic human range of variation, assuming similar body proportions. The Willendorf 2 mandibular symphysis has an inferior lingual torus, a planum alveolare, and a mental trigone with indistinct lateral tubercles, a clear fossa mentalis and a midline basilar rounding. In these features it is close to the majority of European earlier Upper Paleolithic mandibles. 相似文献
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The human frontal bone from al’a, Slovak Republic, has previously entered into discussions of the morphological patterns of Central European Neandertals and the origins of early modern humans in that region. A morphological reassessment of its supraorbital region and a morphometric analysis of its overall proportions indicate that it falls well within expected ranges of variation of Late Pleistocene Neandertals and is separate from European earlier Upper Paleolithic early modern human crania. It is similar to the Qafzeh-Skhul sample in some metrical and supraorbital robusticity measures, but it contrasts with them in mid-sagittal curvature and supraorbital torus morphology. In the context of its probable oxygen isotope stage 5 age based on inferred biostratigraphic associations, it should not be employed directly for arguments relating to the emergence of modern humans in Central Europe. 相似文献
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本文分析了朝阳西沟遗址出土的石制品、动物化石和人牙化石,并考虑到遗址的地层、地貌、年代学和孢粉分析的资料,西沟遗址的石器工业在技术传统上与许家窑、峙峪文化较为接近;但同时也存在一些丁村文化的成分。其时代为晚更新世,距今约5万年。当时这一带属温带半干旱气候的疏林草原环境。 相似文献
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The Xigou site is located at the western side of the confluence of Chaoyangxigou Valley and the Fuhe River, the tributary of the Fenhe River in the Chaoyang village of Quwo county, Shanxi province (111°26 50 E, 35°44'09 N) . It is about 12 KM northwest to the famous Ding- cun site.<br>The Xigou site was found and preliminarily reported in 1956. From Aug. to Sept. of 1983, the author and others made excavation at this site. 514 stone artifacts, one human tooth and some fossils (2 gen. and 4 species) were buried in the sand contained calcarious nodules and a few small gravels from the third terrace. The members of the fossils are Pelceypoda, Gastropoda, Struthio sp. , Equus hemionus, E. przewalskyi, Coelodonta antiquitatis, Bovinae gen. ind. , Antilopinae gen. ind. and Homo sapiens. In he light of geology, geomorphology and the fauna, it is considered that the age of the Xigou Site is the upper Pleistocene. Tested by uranium series method, the date of the Xigou site is about 50, 000 B. P.<br>The artifacts are predominantly made of pebbles of flint and quartz. The scrapers are major component of the assemblage, and the points and burins are the second. The chopper-choPping tools, the bifaces, a saw, a stone ball and a stone hammer are also found. The direct percussion method was mainly used in the industry of the site and the bipolar method was used sporadically. The sides of the flakes were trimmed to become rather straight working edges from the ventral to the dorsal. It is one of the attributes of the industry that the bifacial retouchment makes up relative proportion. According to the worked traces on the edges, the retouching methods were mostly used by stone hammer, a few of them by soft-hammer method. There are most edges of the tools with about 75°. But the repeated retouchment resulted in the rather blunt edges of some tools and abrupt edged scrapers. The most stone tools are medium and small in size.<br>The excavation of this site has raised as many questions as it has answered. We have unearthed artifacts similar to those at Xujiayao and Shiyu in technology and dimension, and discovered the other components similar to those a Dingcun in technology and typology. In 1972, Prof. Jia Lanpo and others proposed two culture traditions in the northern Chinese Old Stone Age. The Xujiayao and Shiyu sites are the meinters of \"the Loc. 1 of Zhoukoudian-Shiyu tradition\", and the Dingcun site represents an example of \"the Kehe-Dingcun tradition\". So the Xigou site can not be classified as belonging exclusively to either one of these two traditions. However, it does appear that the industry at th Xigou site more closely resembles that of the Xujiayao and Shiyu sites. It is necessary to study further into the industries in the Xigou site and two traditions and compare them in details.<br>The pollen analysis indicates that the herbs such as Gramineae, Chenopodiaceae, Artemisia are common, and Pinus are of a little quantity. The majority in the fauna is typical grassland group. An environment of semi-dry, thinly wooded forests and grassland of the temperate zone can be suggested. 相似文献
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Enamel hypoplasia was recorded for the primary and permanent teeth of Natufians (terminal Pleistocene Hunter-Gatherers) and
Early Arabs (Subsistence farmers). Minimal hypoplasia was found in the primary teeth of the Natufians, but in the Early Arab
population, 31% of upper first primary molars showed enamel defects. In the permanent teeth, the Early Arab population again
showed a significantly higher frequency of hypoplasia, with all teeth affected. In the Natufians, only later developing teeth
showed enamel defects. These findings suggest that health status in the Early Arab population was poor throughout life, affecting
pregnant mothers, their foetuses, young infants and children. These results confirm other studies that have shown deterioration
in health status of early agriculturalists relative to hunter- gatherers. Comparisons of these findings with those of recent
populations indicate that health status in the Natufians was comparable to that of modern populations with subsistence diets
and mediocre health care. Health status in the Early Arab population was comparable to that of modern populations suffering
from severe malnutrition and chronic disease. 相似文献