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1.
西藏色林错湖相沉积物的花粉分析   总被引:16,自引:0,他引:16  
通过对藏北色林错湖相沉积物的花粉分析,得到11000年以来该地区植被与环境发展的历史。约11000-9600年前期间,低花粉浓度指示植被稀疏,气候寒冷干燥,与今日的高山稀疏植被相当。约9600-6000年前期间草原代替高山稀疏植被,在大的范围内森林植被扩展,林线下降,气候明显变暖,距今600年以来,植被虽然仍以草原为主,但高花粉浓度及乔木花粉数量的增加都说明植被更加繁茂,气候较现在温暖,直到最近1  相似文献   

2.
A.Gupta 《古生物学报》2002,41(4):517-523
根据从印度库茂恩(Kumaun)喜马拉雅纳尼塔尔(Naini Tal)温带地区获得的85cm钻井的孢粉资料,恢复了1720+/-130年以来晚全新世古植被演变史,并推测了当地的古气候,当前孢粉资料说明了该地区当时发育有栎树混交林和波动的温暖润气候,孢粉组合序列的初始阶段,森林距沉积盆地较远,但是,由于气候变得更加温暖潮湿,森林也很快茂密起来,约1200年前,因气候恶化,森林变得稀疏,而在约124年前,气候再次转好,麦类及其他作物花粉资料证明农耕活动大约开始于1460年前左右。  相似文献   

3.
对采自太湖西部的江苏溧阳市神墩遗址地层的17块土样进行了孢粉分析和研究,结果表明:在距今约7千年以前,研究地区尚无人类活动的痕迹,遗址点周围主要生长常绿和落叶阔叶混交林,如青冈、枫香、胡桃、栎、枫杨、悬铃木、榆和松等,反映比较温暖湿润的气候条件。马家浜文化早期气候温暖湿润,体现出良好的生存环境,但向晚期过渡时,气候环境发生变化,温凉偏干。马家浜文化晚期,遗址周围为亚热带常绿阔叶林,森林繁茂,气候温暖湿润,自然环境比较适宜人类活动与居住。良渚文化时期,木本植物花粉明显减少,草本花粉增加,约占孢粉总数的50%,气候环境为温凉。草本植物花粉中直径大于37μm的禾本科含量很大,达37.1%,可能是先人类进驻,开始进行农作,有水稻和小麦等农作物的大量种植。春秋时期,气候条件比良渚时期要好,较温湿,环纹藻等藻类孢子有较多出现,说明遗址区可能曾被淡水淹没成湖沼环境。  相似文献   

4.
标本采自孟加拉国北部巴拉普库利煤矿晚第三纪上Dupi Tila组,孢粉化石组合中被子植物花粉占优势,其次是蕨类孢子,裸子植物花粉较少且类型单调;被子植物花粉中棕榈科花粉特别繁盛,草本植物花粉含量比较丰富,主要是禾本科和蓼科花粉。通过与现代植物亲缘关系的对比,推断当时该区主要生长有木本棕榈科、蕨类植物及草本被子植物。植被反映当时气候炎热、降水量充沛,可能是一种热带森林沼泽环境。该孢粉组合与印度Ass  相似文献   

5.
江苏句容宝华山全新世中晚期的花粉与环境   总被引:12,自引:1,他引:11  
根据宝华山华山口和官塘头两个剖面的花粉、地层资料,结合植物大化石和^14C年代资料,提示该地区从>6700-5600aBP为稳定的温暖湿润时期;自5600-5100aBP为全新世中期气候的转型时期,冷暖干湿变化较大,前期转凉,旱涝频繁,中期暖湿,后期转冷;大约从4400-4000aBP又变为稳定的暖湿气候。还根据自然保护区现代植被与花粉的关系和与植物大化石共生的沉积物花粉,阐明长江下游新石器时代以  相似文献   

6.
西藏西部札盆地上新世孢粉植物群及古环境   总被引:13,自引:0,他引:13  
孢粉组合以松科两气囊花粉与被子植物藜科花粉为主,禾本科及麻黄花粉有一定的含量,含有少量亚热带常绿或落叶阔叶林分子,蕨类孢子少量,时代属上新世中晚期,亦不能完全排除更新世的可能,孢粉植物群显示比较清晰的植被垂直分带现象,反映了较高海拔下的草原,灌丛草原,亚高山针叶林,低山落叶阔叶林,低山常绿阔叶一针叶林植被,当时气候偏干,可能与现在当地气候已较相似,盆地内地势可能为南低北高,其最低处的海拔可能在2000-2500m左右。上新世至今地势无疑又有1千多米的隆升。  相似文献   

7.
利用共向应面模型进行古气候重建是通过将化石花粉数据与花粉-气候响应模型进行相似对比分析来实现,研究结果表明,在内蒙古中部地区1万年来经历了凉湿期→冷暖干湿剧烈波动期,且有显、温干的气候组合→全新世温暖期→气候波动期的气候变化。  相似文献   

8.
西藏两个小湖高分辨率的花粉记录   总被引:10,自引:0,他引:10  
西藏东南部封闭湖泊高分辨率的花粉记录反映,在16 ka BP以前花粉组合以藜科(Chenopodiaceae) 和蒿属(Artemisia) 为主,花粉浓度很低,应为荒漠草原植被。当时气候寒冷干燥,1 、7 月份和年均温分别低于现在当地7 ~10 ℃,0.5~1.5 ℃和4~6 ℃。年降水量仅250 mm 是现今当地年降水量的40 % ;12 ka BP以后气温和降水逐渐增加,出现木本植物花粉,桦属( Betula) 和松属( Pinus)等,在9 .2~5 ka BP发育森林或森林草甸;8~6 ka BP是研究区气候最适宜期,1、7 月份气温均高于现在2~3 ℃,年降水量比现在当地高100 mm 左右;5.5 ka BP以后气温和降水呈非线性下降,主要发育草原植被,直至现在  相似文献   

9.
北京房山16000—7000年以来的植被与环境变迁   总被引:6,自引:0,他引:6  
对北京房山东甘地8.2m的剖面取样197块,进行高分辨率的孢粉分析和序列的~(14)C测年,对照烧失量测定、炭片统计、表土花粉和古地磁特征等分析,揭示了北京房山里今16000-7000年植被演替及环境变迁的六个阶段、约15780-14700aB.P,当时乔木稀疏,草本类以蒿、藜为优势,由于缺乏水生沼生植物,反映研究区气候干旱。约14700-13400aB.P,由于降雨增多,温度增大,平原区形成小的沼泽环境,水生植物繁盛,泥炭发育。但区域性针阀混交林中主要以寒湿性针叶树种为主,反映寒冷湿润的气候特征。在14060-13520aB.P.泥炭积累中断,为一干冷的气候突变期。约13400-12600aB.P,针阀混交林在山区又进一步发展,平原区水生植物减少,沼泽逐渐疏干,反映气候趋于暖干。约12600-11400aB.P,针阀混交林中呈现以针、阔叶树种交替占优势的现象。水生、湿生植物减少,反映气候有冷暖的波动。约11400-9600aB.P,植被稀疏。在10600-10300aB.P,出现了与新仙女木期时段相当的冷干气候。约9600-7000aBP,阔叶树种增加,反映由典型草原向森林草原的演替,水生植物不繁盛,气候由冷干向温暖转变。  相似文献   

10.
杨志荣 《生态学报》2001,21(4):538-543
以全封闭湖泊调角海子湖相沉积的高分辨率采样为基本分析材料,采用孢粉分析,沉积地球化学分析,14C测年等多种分析手段,对调角海子地区全新世气候与环境进行了综合研究,结果表明:全新世气候与环境演化可划分为5个阶段,其中后两个阶段又可分为3个亚段;全新世大暖期的时代为9400-3800aBP;全新世大暖期具有二分性;6900-6300aBP为全新世气候最适宜的鼎盛期,当时气温比现在高2-3度,降水量至少高于现代150-200mm,植被为针阔叶混交林。  相似文献   

11.
Long term (from the Mesolithic to the Bronze Age) habitation of the Akali settlement on a clearly defined bog-island in East Estonia is used as an example of transitional development from a prosperous foragers’ habitation centre to a hinterland of established farming cultures, taking place through availability, substitution and consolidation phases of crop farming in the boreal forest zone. The pre-Neolithic finds of Triticum and Cannabis t. pollen at c. 5600 b.c. are interpreted as possible indications of the acquaintance of foragers with farming products, through contacts with central European agrarian tribes during the availability phase. The substitution phase is marked by more or less scattered pollen finds of various cereals and hemp and, at Akali, is connected with Neolithic period 4900–1800 b.c. An increasing importance of crop farming in the economy is characteristic of the consolidation phase, but because natural conditions are unfavourable for arable land-use, a regression of human presence is recorded during the second part of the Neolithic. The settlement was abandoned during the Bronze Age at the time when crop farming become the basis of the economy in Estonia. The re-colonisation of the area, traced to ca. a.d. 1200, took place for political reasons rather than through increasing suitability of the landscape.Editorial responsibility: Felix Bittmann  相似文献   

12.
K. Kouli 《Plant biosystems》2013,147(1):195-204
The Neolithic settlement of Dispilió (lake Orestiás, northern Greece) is a unique site due to its continual inhabitation from the Middle Neolithic (5400 BC) to the Chalcolithic (3600 BC) and its exceptional location at the shore of Lake Orestiás (also known as Lake Kastoria). The plant landscape shaping of the area has been examined by correlating pollen and non-pollen palynomorphs from both on-site and off-site records. The examined pollen profiles bear concrete evidence of agricultural activities and land use in the area. The local pollen assemblages identified, each of them corresponding either to a different kind or intensity of exploitation of natural resources, display the diachronic evolution of the cultural landscape during more than 2000 years of human activity. The successive phases of intense human impact on vegetation patterns are in good accordance with the periods of major constructing activities described by the archaeological study of the Dispilió settlement. Finally, the differences on palynomorph accumulation pathways of the examined records made possible the distinction between local and “regional” plant landscapes and related human activities.  相似文献   

13.
The pollen diagram from Tarnowiec concentrates on human impact on vegetation, and is supported by the archaeological background. The earliest evidence of human activities dated at ca. 6500 B.P. was probably connected with the Neolithic Linearbandkeramik culture. Further periods of settlement are recorded at ca. 5200 B.P. and at 4800 B.P. The next very distinct period of intensification in human impact at ca. 4200-3800 B.P. was most certainly connected with the presence of the Corded Ware culture. The next period of settlement occurred during the late Bronze Age, in connection with the development of the Lusatian culture from ca. 3200 B.P. but is recorded only faintly in the pollen diagram. The next colonization phase at ca. 2600 B.P. is possibly the result of Scythian invasions. The widest expansion of human impact came during the period of Roman influence. After this, anthropogenic indicators decreased during the Migration period. The youngest part of the pollen diagram reveals an intensification of anthropogenic indicators connected with early Medieval settlement.  相似文献   

14.
Until recently the recovery of plant remains in Croatia was rare, resulting in few studies addressing the nature of Neolithic crop cultivation. This paper presents new archaeobotanical data from eleven Neolithic settlements in coastal and continental Croatia. Within continental Croatia, three sites dating to the Star?evo culture (early/middle Neolithic; ca. 6000–5300 cal bc) and six to the Sopot culture (late Neolithic; ca. 5300–4000 cal bc) are examined along with two Hvar culture sites (late Neolithic; ca. 4800–4000 cal bc) located along the coast. Different settlement types are included in the study: open air sites, tells and cave sites. From the data collected the most common crops identified were einkorn, emmer, barley, lentil, pea and flax, as well as the fruits Cornus mas (Cornelian cherry) and Physalis alkekengi (Chinese lantern), which were particularly dominant in the Sopot culture settlements. By examining formation processes, sieved crop processing products and by-products were identified at six of the sites, suggesting that cereals were processed on a day-to-day basis at the household level. In contrast, the remains from the late Neolithic coastal cave site of Turska Pe? suggest two distinct formation processes. At the eastern side of the cave the plant remains suggest that episodes of dung burning occurred, possibly to clear the cave of excess waste during seasonal habitation of the cave by herders and livestock. Towards the back of the cave, cereal remains and higher charcoal densities may suggest an area used for food preparation or cooking.  相似文献   

15.
On the basis of pollen analytical investigations of two cores from Lake Varna and Lake Beloslav, the vegetation history of the Lake Varna region is traced back to the beginning of the 6th millennium B.C. A two-fold zoning system is used whereby the pollen diagrams are divided into pollen zones, based on tree migration patterns, and settlement periods. Pollen zone 1 is characterised by the absence of Carpinus betulus and Fagus sylvatica. The spread of hornbeam started at ca. 6500 B.C. (pollen zone 2) and beech at ca. 6200 B.C. (pollen zone 3), the latter being the last tree to spread into the region and considerably enrich the forests of the study area. Of the many pollen taxa representing plants that are favoured by open habitats and hence potentially indicative of human impact, only a few taxa are regarded as reliable indicators of human activity. These include above all Triticum-type, and also Secale and to a certain extent Plantago lanceolata, Rumex and Polygonum aviculare. The spatial pattern of settlements is somewhat different in the areas represented by the two profiles. At both sites the first period of settlement occurred during the 6th millennium B.C. (early Neolithic). After the Neolithic period, the main settlement periods of the Eneolithic and the Early and Middle Bronze Age are recorded. On the other hand, land-use history during the Greek and Roman periods is poorly recorded. Studies on the stratigraphy, diatoms and molluscs indicate that the sixth Black Sea transgression (6500–5800 B.C.), which reached –10 m, had considerable influence on the limnological environment.  相似文献   

16.
Pollen data from the Czech Republic was used to detect the early Holocene impact of hunter-gatherers on vegetation based on a selection of 19 early Holocene pollen profiles, complemented with archaeological information regarding the intensity of local and regional Mesolithic human habitation. Archaeological evidence was assigned to simple categories reflecting the intensity of habitation and distance from pollen sites. Multivariate methods (PCA and RDA) were used to determine relationships between sites and possible anthropogenic pollen indicators and to test how these indicators relate to the archaeological evidence. In several profiles the pollen signal was influenced by local Mesolithic settlement. Specific pollen types (e.g. Calluna vulgaris, Plantago lanceolata, Solanum and Pteridium aquilinum) were found to be significantly correlated with human activity. The role of settlement proximity to the investigation site, the statistical significance of pollen indicators of human activity, as well as the early occurrence of Corylus avellana and its possible anthropogenic dispersal, are discussed.  相似文献   

17.
In this article, we discuss the Neolithic and Early Copper Age (ECA) part of two pollen records from the Middle Tisza Floodplain in association with the local archaeological settlement record. We address the hypothesis of Willis and Bennett (2004) that there was little human impact by farmers on the environment of SE Europe until the Bronze Age. Contrary to this hypothesis, our results show that small-scale agriculture and woodland clearance is already attestable in the earliest Neolithic in Eastern Hungary, there are signs of expanding scale of mixed farming in the Middle Neolithic and strong evidence for extensive landscape alterations with enhanced pasturing and mixed farming in the Late Neolithic (LN) and ECA. The main vegetation exploitation techniques in the alluvial plain of Sarló-hát were selective tree felling (mainly Quercus), coppicing (mainly Corylus and Ulmus) and woodland clearance to establish grazing pastures and small-scale crop farming. Comparison with other well-dated pollen diagrams from Eastern Hungary suggested that, in the Early and Middle Neolithic (8000–7000?cal.?b.p.), Corylus and Ulmus coppicing were probably frequent, while pastoral activities and associated woodland clearance is distinguished in the LN (7000–6500?cal.?b.p.). Our data also suggested a shift to moister summer conditions in the alluvium during the ECA, which may have contributed to a trend towards settlement dispersion and increased reliance on animal husbandry in the NE Hungarian Plain.  相似文献   

18.
Deciduous woodland can be reconstructed as the potential vegetation cover of most parts of the Chernozem (black earth) loess areas settled by the early Neolithic farmers of the Bandkeramik culture in the sixth millennium b.c. The character of the woodland as closed, with few light-demanding plants, or more open is very important for the potential of an agricultural system. Botanical results are not able to indicate the composition of the woods quantitatively, but they can give indirect hints. It is discussed whether these archaeobotanical results, in combination with the characteristics of the wild and domesticated herbivores identified, can be interpreted with regard to the density of the woodland cover in Neolithic times. The use of the floodplains as pasture is interpreted from pollen analytical results.  相似文献   

19.
A stratified profile of the Zhuangbianshan (ZBS) archaeological site (Fuzhou Basin, Fujian) was studied to investigate Neolithic era anthropogenic influence and associated environmental changes. Analysis of the archaeological sediments focused on phytoliths, palynomorphs and microcharcoal. Until now, a lack of direct evidence for agriculture has made it difficult to know if Neolithic cultures of this area relied on the exploitation of wild plants such as nuts and sago palm, or a combination of farming and foraging. Three types of rice phytoliths were found in ZBS archaeological deposits, providing robust evidence for rice farming as part of a broad-spectrum Neolithic subsistence economy centered on fishing and hunting. Chronologies based on AMS 14C dates and artifact typology place the earliest rice during the Tanshishan (TSS) Period (5,000–4,300 cal bp) followed by a shift to economic dependency on rice in the Huangguashan (HGS) Period (4,300–3,500 cal bp). The ZBS phytolith assemblage contains high frequencies of rice husk (peaked-shape glume cells) phytoliths, with far fewer leaf and stem types. This indicates late stage processing activities such as dehusking, implying a focus on consumption rather than rice production. High concentrations of charcoal in the Neolithic ZBS deposits indicate local human settlement and peaks in fire use. The ZBS pollen record also reflects human settlement and peaks in local forest clearance during the Neolithic. Forest cover was renewed when the site was temporarily abandoned following the Neolithic. Rapid formation of the Min River floodplain began ~2,000 cal bp in association with retreating sea level and intensifying anthropogenic influence. Prior to that, rice farming in the Fuzhou Basin was limited by the scarcity of wetlands suitable for agriculture.  相似文献   

20.
The causes and consequences of the Neolithic revolution represent a fundamental problem for anthropological inquiry. Traditional archeological evidence, ethnobotanical remains, artifacts, and settlement patterns have been used to infer the transition from foraging to primary food production. Recent advances in genomics (the study of the sequence, structure, and function of the genome) has enhanced our understanding of the process of plant and animal domestication, revealed the impact that adaptation to agriculture has had on human biology, and provided clues to the pathogens and parasites thought to have emerged during the Neolithic. Genomic analysis provides insights into the complexity of the process of domestication that may not be apparent from the physical remains of bones and seeds, and allows us to measure the impact that the shift to primary food production had on the human genome. Questions related to the location and the process of domestication can be answered more fully by analyzing the genomes of the plants and animals brought under human control. The spread of the agriculture package (plants, animals, and technology) by cultural diffusion or demic expansion can also be investigated through this approach. Whether dissemination by farmers or the diffusion of farming knowledge and technology was the source of the Neolithic expansion, this process should be revealed by the patterh of genetic and linguistic diversity and language found from centers of agricultural Neolithic development. In addition, a number of pathogens that were previously thought to have been transmitted from domesticated species to human now appear to have been present in foragers long before the agricultural revolution took place. Furthermore, we now have evidence that humans were the source of the transmission of some parasites to domesticated animals. For all of these reasons, data from genomic studies are providing a more complete understanding of the origins of agriculture, a critical hallmark in human evolution.  相似文献   

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