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1.
Einkorn (Triticum monococcum L.) was one of the first cereals to be domesticated in the Old World ca. 10,000 years ago and to spread towards Europe and North Africa. Its cultivation declined before the Iron Age and it remains today only as a relic crop in remote areas. To investigate if the geographic distribution of genetic diversity in modern einkorn landrace accessions could be informative about the movement of this crop during prehistory, we genotyped 50 accessions of einkorn from Europe, North Africa and the Near East. Using nuclear and chloroplast microsatellites and clustering methods, we detected two main gene pools in einkorn. The distribution of these lineages revealed differences between accessions from Morocco and the Iberian Peninsula from the rest of Europe and the Near East and suggests different regional dynamics in the spread of this crop.  相似文献   

2.
During the Middle Palaeolithic in the south-eastern Massif Central and the bordering Rhone Valley, humans collected almost all their raw materials from various secondary outcrop which can be distinguished by the inherent characteristics of the materials. Similar lithic facies are unlikely to be encountered on two or more different natural outcrops and every artefact shows a surface that is well enough preserved to be studied according to a morphoscopic analysis at various magnifications. For all sites, some more remote sources were also exploited. However, most of the supposed exogenous materials, such as some Cretaceous flints identified in the Velay assemblages of Sainte-Anne I and Baume-Vallée for example, come from the heart of the massif where they occur in secondary alluvial deposits. Nevertheless, the extent of the foraging territories as revealed by raw materials sourcing covers a large band of various relief between the western and southern Causses, the Rhône corridor and the northern Limagne and Forez plains and animal species hunted by these groups express an environmental mosaic which fits with the image of landscape given by the raw materials.  相似文献   

3.
The analysis of phytoliths, pollen, charcoal and other macroremains was carried out in the neolithic shelter of “La Grande Rivoire”, Vercors massif (French Alps). The results show the predominance of tree species, in the form of phytoliths, clustered pollen, stomata, small branches charcoal, needles, bark, buds… The practice of leaf fodder is already known in the alpine and circum-alpine area from archaeological and historical sources. The analyses of the neolithic dung levels of “La Grande Rivoire” illustrate the use of leafy and flowering tree branches as fodder. The results also suggest that some species were used for special purpose in relation with the tending of livestock (litter, dietary supplement, veterinary practices).  相似文献   

4.
The calc‐alkaline plutonic complex from Charroux‐Civray (north‐western part of the French Massif Central) displays multiphase hydrothermal alteration. Plutonic rocks, as well as early retrograde Ca–Al silicate assemblages, which have crystallized during cooling and uplifting of the plutonic series, are affected by multiphase chlorite–phengite–illite–carbonate alteration linked to intense pervasive fluid circulation through microfractures. The petrographic study of alteration sequences and their associated fluid inclusions in microfissures of the plutonic rocks, as well as in mineral fillings of the veins, yields a reconstruction of the PTX evolution of the Hercynian basement after the crystallization of the main calc‐alkaline plutonic bodies. This reconstruction covers the uplift of the basement to its exposure and the subsequent burial by Mesozoic sediments. Cooling of the calc‐alkaline plutonic series started at solidus temperatures (~650°C), at a pressure of about 4 kbar (1 bar = 105 N m?2), as indicated by magmatic epidote stability, hornblende barometry and fluid inclusion data. Cooling continued under slightly decreasing pressure during uplift down to 2–3 kbar at 200–280°C (prehnite–pumpellyite paragenesis). Then, a hot geothermal circulation of CO2‐bearing fluids was induced within the calc‐alkaline rocks leading to the formation of greisen‐like mineralizations. During this stage, temperatures around 400–450°C were still high for the inferred depths (~2 kbar). They imply abnormal heat flows and thermal gradients of 60–80°C km?1. The hypothesis of the existence of one large or a succession of smaller peraluminous plutons at depth, supported by geophysical data, suggests that localized heat flows were linked to concealed leucogranite intrusions. As uplift continued, greisen mineralization was subsequently affected by the chlorite–phengite–dolomite assemblage, correlated with aqueous and nitrogen‐bearing fluid circulations in the temperature range of 400–450°C. In a later stage, a continuous temperature decrease at constant pressure (~0.5 kbar) led to the alteration of the dolomite–illite–chlorite type in the 130–250°C temperature range.  相似文献   

5.
Abstract

This study addresses the earliest strategies of permanent occupation in the mountainous regions bordering Northern Meseta in inland Iberia. This piece of work gathers together and discusses archaeological information about settlement in the Late Bronze Age and Early Iron Age and previously published high-resolution palynological cores from three study areas. Its major goal is to assess both archaeological and pollen records in order to gain a better understanding of the dynamics of occupation and transformation of these upland settings. Until cal 700 BC there are no clear signs of permanence in the highlands surrounding the Duero basin, but from that point onwards various initiatives of small-scale spontaneous colonisation have been identified. Colonisation in the Iron Age involved pastoralism, cereal agriculture and a significant use of forestry resources, causing a major anthropogenic impact with irreversible consequences. The outlined account constitutes the first synthetic overview at a macro-regional scale on the beginnings of the integrated and diversified strategies implemented in these upland regions.  相似文献   

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7.
Abstract

A study of plant remains from seven archaeological wells at Mas de Vignoles IX, near Nîmes, southern France, was used to shed light on a current gap in the archaeological record caused by erosion and modern agriculture. The analysis also explored the reliability of these sources for palaeoenvironmental and palaeoeconomical information. Significant results on the spatial organization of human habitation, economic activities, and on the environment and its exploitation were obtained for the Middle Neolithic to Roman periods. Furthermore, the Neolithic wells also provided the first early finds of fig seeds in France. The abundance of weed and ruderal plants up to the Iron Age is consistent with data from other studies and their dramatic decrease during the Roman period may have resulted from radical changes in land management. The study marks the first time, in southern France, that a group of wells from a single site have provided a complete record throughout the later prehistoric and Roman periods.  相似文献   

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The Middle Son valley in north-central India preserves extensive Quaternary alluvial deposits. A long history of archaeological and geological research in the valley has resulted in the discovery of lithic assemblages ranging from Lower Palaeolithic to microlithic, a rich corpus of fossilised faunal remains, and ash deposits from the 74,000 year-old Toba supereruption. This paper reviews the chronology and stratigraphy of the valley’s Quaternary sediments, and presents a model that hypothesizes the temporal sequence of important lithic assemblages from excavated and surface contexts. Artefacts in these assemblages are analysed and changes in lithic technology through time are described; this evidence is used to propose shifts in hominin behaviour and demographic structure in this region during the Upper Pleistocene. Recognising gaps in our understanding of the Middle Son record, future avenues of research are recommended that will build upon previous research and address questions of palaeoanthropological significance. The Middle Son valley preserves a long and rich record of hominin occupation from all periods of the Palaeolithic that is rarely paralleled by other sites in India.  相似文献   

11.
Quartz veins in the early Variscan Monts d’Arrée slate belt (Central Armorican Terrane, Western France), have been used to determine fluid‐flow characteristics. A combination of a detailed structural analysis, fluid inclusion microthermometry and stable isotope analyses provides insights in the scale of fluid flow and the water–rock interactions. This research suggests that fluids were expelled during progressive deformation and underwent an evolution in fluid chemistry because of changing redox conditions. Seven quartz‐vein generations were identified in the metasedimentary multilayer sequence of the Upper Silurian to Lower Devonian Plougastel Formation, and placed within the time frame of the deformation history. Fluid inclusion data of primary inclusions in syn‐ to post‐tectonic vein generations indicate a gradual increase in methane content of the aqueous–gaseous H2O–CO2–NaCl–CH4–N2 fluid during similar P–T conditions (350–400°C and 2–3.5 kbar). The heterogeneous centimetre‐ to metre‐scale multilayer sequence of quartzites and phyllites has a range of oxygen‐isotope values (8.0–14.1‰ Vienna Standard Mean Ocean Water), which is comparable with the range in the crosscutting quartz veins (10.5–14.7‰ V‐SMOW). Significant differences between oxygen‐isotope values of veins and adjacent host rock (Δ = ?2.8‰ to +4.9‰ V‐SMOW) suggest an absence of host‐rock buffering on a centimetre scale, but based on the similar range of isotope values in the Plougastel Formation, an intraformational buffering and an intermediate‐scale fluid‐flow system could be inferred. The abundance of veins, their well‐distributed and isolated occurrence, and their direct relationship with the progressive deformation suggests that the intermediate‐scale fluid‐flow system primarily occurred in a dynamically generated network of temporarily open fractures.  相似文献   

12.
受地理环境和历史人文环境影响,莒南县平原和低山丘陵区在地权分配状况上呈现截然不同的特点,平原区地权集中,多大地主,租佃关系发达,多采取土地大块出租的方式,带有资本主义经营性质的富农大佃户居多,地主采取的剥削形式以地租剥削为主;低山丘陵区地权分散,多经营地主,租佃关系少,且多小块出租,自耕农占绝对优势,在剥削关系上也以雇工剥削为主。中共地方组织在贯彻中央减租减息的土地政策时,既要考虑当地特点,又要保证中央政策的执行,因此,不得不采取变通形式,针对平原区多大佃户的情况而采取“拔地”、针对低山丘陵区雇工经营发达的实际而采取“增资”,以及其他诸如“找工”、“借粮”、“找问题”、“开斗争会”等措施,使地主富农的地权及其他财富逐渐向贫雇农转移,使减租减息运动在客观上达到了土地改革的目的。  相似文献   

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