木雕文物的褐腐菌害

为对一尊唐代木雕佛像严重朽蚀的原因进行调查,用扫描电镜观察,对样品的综纤维素、木质素含量等进行分析测定,并对菌进行培养。实验结果表明,木材纤维中有菌丝,真菌孢子,经一定温湿度培养后,腐朽木材上的孢子有发展,说明该真菌在原介质上存活,在合适的环境条件下,将会继续起菌害作用。分析数据说明,综纤维素含量大大降低,木质素的相对百分比含量大大升高,这是综纤维素及其相伴生的戊聚糖受真菌破坏分解的结果。此等菌害的表现应该是属褐腐菌对木材破坏的结果。由于褐腐菌对木材短时间内就能产生强大的破坏力,因此,对木质物的保护要特别重视褐腐菌的侵害。     

荆州博物馆文物展陈环境空气中真菌数量及其群落特征

存在于空气中的微生物种类极其丰富,空气中有害微生物对文物安全和游客健康构成威胁,国内外博物馆均开展了馆内空气微生物的研究。为研究荆州博物馆文物展陈环境空气中真菌数量及种群分布,调查潜在的有害微生物,采用自然沉降法对3个展柜及其所在的展厅进行空气真菌采样。对分离到的真菌菌株进行形态和分子鉴定,并分析群落分布特征。结果显示:展厅中真菌数量范围为17～74 CFU/m~3,展柜中真菌数量在12～21 CFU/m~3之间,青铜器和木漆器的展柜中真菌数量显著低于展厅(P0.05);纺织品展柜和展厅中真菌数量无显著性差异(P0.05)。共发现19属真菌,展柜空气中分离出8属真菌,展厅空气中分离出17属真菌。枝孢属(Cladosporium)和小球腔菌属(Leptosphaeria)分别占真菌总数的24.76%、22.86%,为优势真菌。枝孢属普遍存在于展厅和展柜中,小球腔菌属主要存在于展厅中,卵形孢霉(Oospora)和链格孢属(Alternaria)真菌为展柜特有菌。总体而言,荆州博物馆展陈环境中展厅真菌数量和种类多于展柜,木漆器展厅真菌数量最高,种类最丰富。博物馆展厅和展柜在6月和7月温度、相对湿度有利于真菌类微生物滋长,枝孢属和小球腔菌属作为展陈环境中优势菌属,在适宜的环境下,容易大规模生长,对文物或人体具有一定危害,可采取空气消毒措施。该研究结果对了解馆内空气污染现状,保护游客健康和文物安全具有重要的现实意义,可为馆藏文物的预防性保护提供科学依据。     

Wrap a Wreck! In Situ Conservation of a Ship on Land Suffering from Fungal Decay

Many sixteenth- to eighteenth-century shipwrecks have been found after land reclamation in parts of the former Zuiderzee, one of the busiest waterways in Dutch history. After the land fell dry, some shipwrecks were excavated, destroyed, reburied, or covered with sand or clay. In the late 1970s a method was developed to mitigate degradation processes of some of the wrecks remaining in good condition by wrapping them in plastic foil. The idea was that the plastic would prevent evaporation and lateral subsurface flow. Wet conditions prevent decomposing of wood by especially soft rot fungi. Oxygen will be rapidly depleted by decomposition of organic matter.

Recent monitoring of wrapped shipwrecks has shown that this method of preventing rot worked exceptionally well. We adapted wrapping using new technology nowadays applied for sealing tunnels and landfills. We will present the implementation requirements, materials and new adapted method for wrapping shipwrecks.     

New data on relevant ancient Egyptian wooden artifacts: Identification of wooden species and study of the state of conservation with multidisciplinary analyses

Wood species identification and characterization of its weathering processes are crucial steps in the scientific approach of conservation of wooden cultural heritage. Many precious wooden objects of ancient Egypt are largely present in museums, nevertheless relatively little information is available concerning the nature of timber used and on their status of conservation. To address this gap, the wooden species of three relevant archaeological wood objects (statue, box, and coffin) arising from different Egyptian archaeological sites dated from the Old Kingdom (2,686–2,181 BC) to New Kingdom (1,550–1,069 BC) were deeply studied. Five hardwood and softwood species were identified belonging to Tamarix mannifera, T. gennessarensis, Ficus sycomorus, Vachellia nilotica, and Cedrus sp. Such data confirmed the recurrence of Vachellia and Tamarix among the most common timbers found in ancient Egypt. Scanning electron microscope, Fourier transform spectroscopy, and synchrotron x-ray radiation diffraction were conducted to evaluate the archaeological wood deterioration. The formation of microcracks, biological degradation patterns (fungal colonization), or chemical characterization (accumulation of salts on and in-between wooden cells) were detected. SEM micrographs showed the presence of fungal hyphae and conidial spores on the wooden cells. Significant changes in the chemical wood composition and decrease in the crystallinity index were detected.     

Physical Characterization,Microstructural Evaluation,and Condition Assessment of Ancient Ahlat Tombstones in the Seljukian Cemetery of Ahlat (Turkey)

A typical Seljukian town of Ahlat, located between the north-western shores of the Lake Van and the Nemrud and Suphan volcanoes of the Eastern Turkey is hosting rich and colorful cultural heritage sites. Among these, famous Seljukian Cemetery is a major archeological district with monumental tombstones (stelae). Excessive deterioration, erosion and lichen colonization can be observed in these cultural artifacts. The main objective of this study is the investigation of stones’ physical characterization and evaluation of the microstructural features. A degradation model was outlined starting with the capillary water uptake from the bottom section and lichen colonization starting from the top and covering these tombstones upto their mid sections. This article provides some information about the historical town of Ahlat and its tombstones. Some physical and microstructural characterization of the gravestones and the results of chemical and physical analysis are also presented along with some recommendations.     

On-site Radioscopic Qualitative Assessment of Historic Timber Structures: Identification and Mapping of Biological Deterioration of Wood

The recent development of portable, battery-charged x-ray tubes and digital detectors has made digital radioscopic examination of wooden buildings a realistic option. Lack of experience with the often very complex radiographs of building structures makes the interpretation of such radiographs difficult. A set of radiographs of wood in different, identified conditions was established for use when interpreting radiographs of wood in unknown condition.

This article presents radiographs of a trestle-framed building. The recordings were done in areas where the condition of the wooden elements was known in advance, either on the basis of dendrochronological drill samples or because the building element had been replaced recently and the wood was sound. The radiographs were compared with NIKU´s collected guideline radiographs and discussed with respect to the information they provide about the wood’s condition. Finally, we discuss radioscopy as a supplement to traditional methods of building surveying.

The authors took all of the photos and radiographs (©NIKU). The radiographs are shown as “shadow” images—materials of higher density are seen lighter than materials of less density, as long as they are of same thickness.     

生物酶对跨湖桥遗址丝状真菌抑菌作用的研究

确定萧山跨湖桥遗址空气、土壤、字幕墙和独木舟侵蚀丝状真菌的种类,探讨生物酶对侵蚀丝状真菌的有效抑菌浓度,为消除生物危害提供参考依据。采用经典方法对侵蚀丝状真菌进行分离、鉴定,并对生物酶的有效抑菌浓度进行研究。空气中主要的丝状真菌有:黑曲霉(Aspergillus niger)、土曲霉(Aspergillus terreus)、展青霉(Penicillium patulum)和圆弧青霉(Penicillium cyclopium)。土壤中主导菌为黑曲霉(Aspergillus niger)、土曲霉(Aspergillus terreus)、聚多曲霉(Aspergillus sydowii)、杂色曲霉(Aspergillus versicolor)、圆弧青霉(Penicillium cyclopium)、展青霉(Penicillium patulum)、黑青霉(Penicillium nigricans)、宛氏拟青霉(Paecilomyces varioti)和枝孢霉(Cladosporium)。字幕墙侵染菌为杂色曲霉(Aspergillus versicolor)。独木舟侵蚀菌为宛氏拟青霉(Paecilomyces varioti)。不同的丝状真菌对生物酶的感应性/耐受性有很大不同。单一的几丁质酶对丝状真菌的生长发育有抑制作用,但几丁质酶和葡聚糖酶的复合协同作用更能有效地抑制丝状真菌的生长发育。     

An Ethnoarchaeological Case Study of Dung Fungal Spore and Faecal Spherulite Taphonomy in a Pastoral Cave Deposit

ABSTRACT

In alkaline cave sediments, the presence of faecal spherulites is regarded as a reliable indicator of animal dung. Spores of coprophilous fungi are nowadays frequently employed as grazing indicators in palaeoecological sequences, but their use in dryland pastoral deposits is not routine in geoarchaeological practice. The paper assesses the relationship between the occurrence of spherulites and dung fungal spores from an abandoned rock shelter used as a stable for several decades. A clear match between these proxies is shown, and their distribution across the sediments is discussed, highlighting the potential of coprophilous spore analysis from archaeological stabling deposits, alongside other established dung indicators. The abundance of other microfossils (parasite eggs, coccolith plates and freshwater indicators) is also quantified and discussed.