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Ungulate footprint-tracks provide information regarding the species and age of animals. Combined with other datasets, this contributes to interpretation of seasonal husbandry patterns in the Severn Estuary, focusing on Bronze Age intertidal footprint-tracks at Redwick and Goldcliff East and the Late Neolithic site of Oldbury. Metric dimensions and morphology of modern contemporary ungulate footprint-tracks are used as analogues to help understand the species and age of prehistoric ungulates. Findings indicate that Dexter cattle and Soay sheep are metrically similar to British prehistoric ungulates. The prehistoric sites have a concentration of neonatal and juvenile individuals. Along with evidence provided by environmental data, faunal skeletal assemblages and lipid and isotopic analysis, this leads to the conclusion that the presence of younger animals and evidence at Brean Down for dairying is consistent with saltmarsh grazing activity in spring and summer.  相似文献   
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位于长江入海口的“长江口二号”清代沉船是中国目前发现的保存最为完整的古代木制沉船之一,已于2022年11月完成整体打捞。在进行水下考古调查时,沉船出水的部分青花瓷出现的病害现象引起了考古工作者的关注,特别是裂纹中黑色污染物及表面铁锈状污染物对文物的外观产生了很大影响。本工作选取了三件具有典型被污染特征的青花瓷标本作为代表,使用能量色散X射线荧光分析(EDXRF)、光学显微镜(OM)、X射线衍射分析(XRD)、拉曼光谱分析(Raman)和扫描电子显微镜-能谱分析(SEM-EDS)等方法,对污染物进行了研究,探讨了其形成原因以及环境的影响作用,并对其潜在危害进行了分析。研究表明,污染物主要以方解石、菱铁矿等碳酸盐以及铁的氧化物、氢氧化物和硫化物为主。长期处于河口淤泥中的还原性环境是导致菱铁矿和亚稳的铁硫化物形成的原因,船体中铁质构件腐蚀对局部环境的污染是重要的影响因素,这也反映出被污染的青花瓷所处位置和环境的特殊性。出水的部分青花瓷釉中裂纹的形态表明其形成是由物理撞击造成,而釉中硅灰石晶体的选择性腐蚀会导致腐蚀坑的形成,裂纹和腐蚀坑均为外部污染物进入釉层内部提供了通道,导致瓷器劣化。出水后...  相似文献   
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West Tump is a Neolithic chambered tomb originally excavated in 1880. The mound was found to contain a mixed skeletal assemblage, the majority of which was disarticulated. Between 2000 and 2001 material from the site including human bone was re‐examined with a portion of this project focused on taphonomic evidence observed on the human skeletal material. Amongst the factors selected for investigation were deliberate toolmarks. Three specimens were identified as exhibiting toolmarks. Analysis demonstrated that the observed features were cutmarks, consistent with the use of flint tools. However those on two of the specimens were found to be both post‐mortem and recent. The cutmarks observed on the remaining specimen, a right clavicle, were identified as having been inflicted during the peri‐mortem period and consistent with decapitation. British Neolithic mortuary practice has been the subject of ongoing debate since the earliest excavations of relevant sites, but until very recently few assemblages from such contexts have been re‐examined and much of the data in use has derived from sources of considerable age and questionable reliability. The selective removal of specific skeletal elements (particularly skulls) has repeatedly been described in the literature regarding the collective funerary monuments of this period. It has often been assumed that such practices took place after the soft tissues had decayed. One of the examples discussed, suggests this may not always have been the case and the potential significance of this finding is discussed in addition to a possible interpretation of the cutmarks seen on the remaining specimens. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
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珠海宝镜湾遗址是珠江口地区一处面积较大的未经后世扰乱的山坡遗址。近期小规模的试掘使我们对遗址的文化性质、时代及所反映的社会经济形态有了一个初步的认识。  相似文献   
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Resilience is held as a promising concept to produce a paradigm shift from traditional flood control to an integration of flood risk management and spatial planning. Central ideas to the resilience narrative are that ‘nothing is certain except uncertainty itself’ and ‘adaptability’ is key to ‘governing the unknown’. However, this terminology is far from clear, yet increasingly used, which raises the question how it is made sense of in practice. To answer this question, we examine two long-term flood risk management strategies in the London and Rotterdam region with a policy framing perspective (i.e. the English Thames Estuary 2100 Plan and the Dutch Delta Programme). In both strategies, uncertainties are a key concern, leading to adaptive strategic plans. Reconstructing the framing processes shows that the English adopted a ‘scientific pragmatism’ frame and the Dutch a ‘joint fact-finding’ frame. While this led to different governance approaches, there are also striking parallels. Both cases use established methods such as scenario planning and monitoring to ‘manage’ uncertainties. Similarly to previous turns in flood risk management, the resilience narrative seems to be accommodated in a technical-rational way, resulting in policy strategies that are maintaining the status quo rather than bringing about a paradigm shift.  相似文献   
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While bone stable isotope signatures of humans foraging in open coastal and fully terrestrial environments have been relatively well documented, the signature of foraging near brackish-water estuaries is less well known. This study examines the Central California isotopic landscape, or isoscape, showing how foods in different ecosystems have distinctive isotopic compositions. We present new bone collagen and apatite stable isotope data from two Late Holocene sites (CA-SOL-11 and CA-SOL-69) near Suisun Marsh, a low salinity brackish water estuary upstream from San Francisco Bay. Faunal remains at the sites include significant numbers of aquatic resources including fish and shellfish, in addition to terrestrial mammals, while paleobotanical remains suggest mainly terrestrial nuts and seeds. Stable isotope data at the population level corroborate this finding and show consumption of significant levels of brackish water nutrients, including both dietary protein and dietary carbohydrates and fats, paired with terrestrial foods. This dietary focus generates a unique brackish-water isotopic signature that is distinct from others in Central California. The documentation of an isoscape with strong regional gradients can be of tremendous help in reconstructing ancient patterns in subsistence, migration, and trade.  相似文献   
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本研究基于GIS技术构建网格体系,处理三份近代实测海图汇编资料,重建了长江口南支河段(徐六泾口-吴淞口)1861-1953年期间的冲淤强度及其分布,基本理清了19世纪中期——20世纪中期现代观测制度确立前研究区内河槽冲淤状况及变化过程,19世纪中期——20世纪初期南支处于强烈冲刷阶段,至20世纪中期冲淤大体平衡而略有淤积;其中≤3m和≥10m水域的冲淤变化状况最为明显。今南支航道体系的形成是在19世纪中期——20世纪中期自然冲淤基础上进行人工整治的产物。在重建冲淤状况的基础上,对崇明县城南侧扁担沙——南丰沙的变迁过程进行重建,以此为例探讨了典型河槽断面的演化过程。  相似文献   
8.
近年来,针对文物在海水中的细菌性腐蚀研究主要集中于海域沉积,但关于咸淡水混合水域的腐蚀性细菌研究鲜有报道。河口及近海岸水域是水下文物较为丰富的区域,咸淡水交互作用影响水下文物的埋藏环境和文物遗存。本研究采集长江口北港拦门沙Ⅱ号沉船附近海底不同层次的海泥,通过非定向富集培养基培养,分离纯化得到18株菌,经16S rDNA鉴定出4种具有腐蚀性的细菌:哈夫尼希瓦氏菌(Shewanella hafniensis)、越南芽孢杆菌(Bacillus wiedmannii)、金橙微小杆菌(Exiguobacterium aquaticum)和微小杆菌(Exiguobacterium indicum)。将分离得到的细菌作用于瓷质、陶质和木质等常见文物材料,置于30℃摇床220 r/min转速下培养7 d,喷金干燥,扫描电镜下观察,均可见在材料表面上产生生物膜。生物膜与微生物腐蚀的发生密切相关,除了已报道具有腐蚀性的菌株外,还发现了2株先前并未报道但也在材料表面产生生物膜的菌类:萘醌对希瓦氏菌(Shewanella xiamenensis)和嗜水气单胞菌(Aeromonas hydrophila)。实验...  相似文献   
9.
Stable isotope analyses of modern coastal and salt-marsh plant species (‘salt-loving’ plants or halophytes) have demonstrated that these are significantly enriched in 15N compared to other terrestrial plants. Coastal salt-marshes were far more extensive in the past than they are today. They represented a vast and much-exploited resource in many areas of the UK and north-western Europe and were considered to be prime land for the grazing of animal stock.  相似文献   
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