The potential of chironomid (Insecta: Diptera) larvae in archaeological investigations of floodplain and lake settlements

The head capsules of chironomids (Insecta: Diptera) are well preserved in sediments and can be recognised to a high taxonomic level, usually genus and sometimes species. Work on lake sediments has shown that they can be accurate indicators of water temperature, oxygen regimes, and nutrient status (particularly total phosphorus and chlorophyll-a), as well as heavy metal pollution. No systematic chironomid analyses, however, have previously been undertaken on archaeological deposits. In order to address this we assessed the use of chironomids in three types of archaeological deposit; firstly, a lake core at the edge of a lake settlement (crannog), secondly, a palaeochannel infill adjacent to a multi-period settlement site and lastly, a Roman well deposit from a floodplain environment. The chironomid assemblages are shown to vary significantly both between and within the sites and reflect the immediate environment and the adjacent area. The lake sediment assemblage reflects the construction of the crannog through elevated levels of organic detritus, wood and woody debris. The palaeochannel assemblage reveals changing natural conditions and nutrient enrichment probably associated with settlement during the Saxon period. The well assemblage is taxonomically restricted and indicative of organic debris, dead plant material, animal dung and possibly human effluent deposited after abandonment of the well. Dry storage of the palaeochannel and well sediments for several years did not appear to affect the concentration or state of preservation of the head capsules. The chironomid reconstructions are shown to provide an additional indicator of human activity which has the potential to provide quantitative data on the character of aquatic environments associated with archaeological sites.     

From pedologic indications to archaeological reconstruction: deciphering land use in the Islamic period in the Baida district (north-western Sicily)

The aim of this work was to detect imprints on soil properties from former Islamic land use (9th to 11th century) using a multi-method, soil-chemical approach. Four soil profiles (with buried horizons) found in the vicinities of former Islamic settlements in Sicily were analysed for phosphorus (total, organic and inorganic), nitrogen (total, NO₃⁻ and NH₄⁺), carbon compounds (δ¹³C, lipids, polycyclic aromatic hydrocarbons (PAH) and functional groups), physical and chemical C-fractions and the state of soil weathering. Two soil profiles contained ceramic sherds from the Islamic period. Inorganic nitrogen forms, phosphorous and the PAH content indicated strong impacts from traditional agriculture and/or burning. Radiocarbon dating of soil organic carbon (SOC) fractions from buried horizons showed that distinct changes must have occurred during the Islamic epoch. The isotopic composition of SOC indicated that land use was probably different in earlier times. C₄ plant cultivation was expected but surprisingly lipid analyses did not confirm this. A high amount of aliphates and low C/N ratio indicated a good, long-term SOC stabilisation under the native conditions combined with Islamic land use. The irrigation of the soils probably increased the production of weakly-crystalline Fe forms that helped to stabilise SOC.     

古代钢铁制品中的浮凸组织初步研究

为研究钢铁制品中浮凸组织产生的原因,对14件取自不同地方、属于不同时期的具有浮凸组织的样品利用金相组织鉴定、扫描电镜能谱分析、化学分析和显微硬度测定等方法进行了研究。结果表明：金相组织观察发现浮凸组织与夹杂物和铁素体晶粒间界有一定的关系,并存在有不同的形貌,其显微硬度均比附近基体高;成分分析表明有浮凸组织的样品磷含量要比没有浮凸组织的样品磷含量高一个数量级。有浮凸组织样品内部磷含量的分布也不均匀。这些结果说明,浮凸组织的产生主要原因是矿石中的磷在冶炼过程中进入铁中,而在随后的脱碳退火、炒炼和冷、热加工过程中均不能有效地脱去;同时,固溶在铁中的磷与铁形成薄膜阻止晶粒间界长大、或在埋葬条件下长期时效引起的晶界移动而产生了浮凸组织。     

Let no space go to waste: comparing the uses of space between two Late Classic centers in the El Paraíso valley,Copan, Honduras

Phosphorus analysis of earthen and plaster floors has been used in Mesoamerica to locate and identify activities at ancient sites. This study uses phosphorus analysis to discern if the inhabitants of two Late Classic coeval and proximal sites located in the El Paraíso Valley of Honduras were different culturally from each other. The buried earthen and plaster surfaces of both sites were systematically sampled and analyzed for phosphorus remains. The patterns of elevated phosphorus from these open spaces were subsequently compared to determine if differences in the habitual use and treatment of open spaces could be discerned. These differences are evaluated as a function of behavioral norms, functional responses, and cultural dispositions in order to evaluate the extent to which these two populations were indeed different from each other.