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101.
良渚古城老虎岭水坝遗址是我国迄今发现最早的大型水利工程系统中的一处典型遗存,对中国文明起源和世界文明史的研究具有重要意义。为清晰地展示老虎岭水坝土遗址上“草裹泥”筑坝工艺的痕迹,针对温热、潮湿、多雨环境土遗址保护的难题,在总结吸取国内土遗址保护经验教训的基础上,借助浙江大学的研究成果和敦煌研究院的工程经验,提出了一套避免使用化学材料加固,而以“黑屋+隔水+控湿”为主的小环境控制工程策略,包括:构建遮光大棚以避雨和抑制绿色生物生长;铺设防水毯以防止坝体渗水;设置电加热玻璃罩以保湿和封闭展示面;采用气相补水以调控空气湿度和土体含水率;采用植物精油等绿色环保技术防治微生物;同时做好遗址实时监测和管护等。这套综合保护措施是土遗址保护理念和工程实践的一次新的尝试。  相似文献   
102.
为了促进微生物学理论与技术在我国文物保护领域中的应用,使我国的文物保护与国际先进水平接轨,本文通过对国内外有关文物保护微生物学研究进展的综述,阐述了饱水木质文物细菌性病害的成因和机理.侵蚀细菌、钻管细菌和空化细菌是饱水木质文物细菌性病害的病原体,但它们的作用方式有一定的区别.在饱水木质文物细菌性病害诊断上,国外已较为普遍地使用了光镜技术、电镜技术、细菌培养技术以及多种分子生物学技术.根据众多样本分析的结果,国外学者已建立评价饱水木质文物腐蚀状态的定性指标体系.文中还结合目前我国有关饱水木质文物保护的现状,阐述了文物保护微生物学在我国饱水木质文物保护中的应用前景,并建议尽快开展相关的研究工作.  相似文献   
103.
A survey of soil erosion was conducted in Australia using the fallout radioisotope caesium‐137 as an indicator of topsoil redistribution. Two hundred and six sites were sampled, 100 within rotational cropping and horticultural use, 52 within uncultivated permanent pasture and forest, and 54 in rangelands. Average net soil losses were approximately equal for cultivated cropping lands and rangelands (ca. 5.5 t ha?1 yr?1), and just over 1 t ha?1 yr?1 for pasture and forest. The Mann Whitney U Test revealed that losses under cropping and rangeland conditions were significantly higher (p < 0.05) than under uncultivated pasture and forest. Soil loss was negatively correlated with mean annual rainfall and slope gradient, and positively correlated with slope length (Spearman's rank correlation). There was no correlation between rates of soil loss and a rainfall erosi‐vity index. An assessment of erosional events was provided by landholders for 104 sites, with their ranking being weakly but significantly correlated with soil loss estimates (r =+0.35). Sixty percent of sites had net soil losses greater than 1 t ha?1 yr?1, and 74% of sites had losses of more than 0.5 t ha?1 yr?1. This latter rate may be regarded as a limit for a tolerable level of soil loss. These high rates of soil loss have occurred since the mid‐1950s despite there being significant landholder awareness of the soil erosion hazard.  相似文献   
104.
通古斯巴西古城遗址是新疆重要的土遗址之一,原为唐龟兹驻兵的安西都护府所在地。遗址中曾出土大批文物,对于研究西域的屯垦历史和古代城址布局等有重大意义。为了系统地研究了通古斯巴西古城遗址土的工程特性,在实地调查的基础上,通过室内试验对通古斯巴西古城遗址土的物理、力学、水理和化学性能进行测试。此外,还测定了不同PS浓度加固后遗址土重塑土块抵抗风蚀雨蚀能力的差异,进一步确定了PS的渗透加固措施对土质文物的防风化及雨蚀效果。结果表明,7%的PS溶液防风化抗雨蚀效果要更为显著。研究结果可为PS的施工应用提供依据。  相似文献   
105.
左江流域水土流失现状与治理措施   总被引:3,自引:0,他引:3  
左江流域包括扶绥、崇左、宁明、龙州、凭祥、大新六县市,位于南宁地区的西南部。由于长期以来不合理的开发利用,致使水土流失现象十分严重,不但有面蚀、沟蚀,有些地方甚至发展成崩岗。该区域总面积15092.39Km2,水上流失面积525.81Km2,本文在分析水土流失现状及成因的基础上,提出相应的水土保持措施。  相似文献   
106.
The fate of artifacts incorporated into the ploughsoil as a result of plough damage is considered in terms of two soil mark sites near Winchester, Hampshire. Ploughsoil and subsoil analyses indicate that dispersal of soil material, as a result of ploughing, is limited at the present time and under mould board ploughing techniques. The origin of soil marks underlain only by bedrock is also considered and evidence indicates that such soil marks may appear as groundsurface expressions of ditches which have been removed by plough damage where dispersal of ploughsoil is minimal. Such soil marks may be only short lived if plough depth continues to increase.  相似文献   
107.
Recent research involving starch grains recovered from archaeological contexts has highlighted the need for a review of the mechanisms and consequences of starch degradation specifically relevant to archaeology. This paper presents a review of the plant physiological and soil biochemical literature pertinent to the archaeological investigation of starch grains found as residues on artefacts and in archaeological sediments. Preservative and destructive factors affecting starch survival, including enzymes, clays, metals and soil properties, as well as differential degradation of starches of varying sizes and amylose content, were considered. The synthesis and character of chloroplast-formed ‘transitory’ starch grains, and the differentiation of these from ‘storage’ starches formed in tubers and seeds were also addressed. Findings of the review include the higher susceptibility of small starch grains to biotic degradation, and that protective mechanisms are provided to starch by both soil aggregates and artefact surfaces. These findings suggest that current reasoning which equates higher numbers of starch grains on an artefact than in associated sediments with the use of the artefact for processing starchy plants needs to be reconsidered. It is argued that an increased understanding of starch decomposition processes is necessary to accurately reconstruct both archaeological activities involving starchy plants and environmental change investigated through starch analysis.  相似文献   
108.
For over a decade, multi-element chemical analysis of floor sediments in archaeological contexts has been a tool to identify and interpret anthropogenic chemical residues and activities. For the current study, a multi-element chemical analysis was applied to floor samples from a Classical-Hellenistic courtyard building at Düzen Tepe (SW Turkey). Among a series of 19 elements analyzed, K, Mg, Fe, P and Sr are thought to directly reflect anthropogenic chemical residues. The elements Cr, Mg, Ni, Pb and Ti are considered to reflect the geological background of the site, yet their contents seem to vary over different chemical residue zones, making them a suitable tool for delineating activity areas. Overall, the sampling and analysis techniques applied at Düzen Tepe – mild acid sample extraction and ICP-OES analysis – have proven to be fit for this kind of study. The analyses allow human activity zones within the study area to be identified and interpreted and deliver insights into the archaeological contexts that could not be obtained by archaeological research alone.  相似文献   
109.
前言寄生物考古学是近30年来兴起的一门科技考古的分支学科,它以考古中发现的寄生虫遗存为研究对象,通过还原古代寄生虫感染的流行分布,结合其他考古信息,了解当时影响寄生虫感染的各种因素,如人群交流、迁徙、水资源、生业模式、社会阶层、自然环境、医药卫生等等,考察古人或与人相关  相似文献   
110.
为综合研究出土玉器的风化机理,正确评估玉器的保存状况,本研究采用物相、成分和电镜等方法对2016年广州重要考古发现——增城墨依山玉器进行了材质和结构分析,确认了墨依山玉器材质为透闪石。在此基础上,对玉器周边土壤进行了物相、成分、结构和酸碱度等分析,并结合玉器本体和遗址气候条件,综合探讨了强酸性环境下墨依山玉器的受沁过程。本研究有助于丰富对玉器风化机理的认识,有利于科学制定玉器的保护措施。  相似文献   
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