Detection of Human Landscape Alteration Using Nested Microbotanical and Fungal Proxies

ABSTRACT

Fungal spores and other ‘non-pollen palynomorphs’ are an overlooked and valuable analytical resource available to palaeoecologists and archaeologists as part of a multi-proxy dataset. Both complementary and antagonistic data gleaned from these analyses are useful for making inferences concerning past human behaviour, as anthropic activity may have many microbotanical correlates. The use of fungal spores in palaeoecology and archaeology is reviewed, followed by analysis of pollen, fungal spores, and microcharcoal from a sediment core collected at Mtwapa Creek, Kenya. These proxies are analysed against palaeoclimatic data from the region in order to identify unexpected patterns and hypothesise as to possible scenarios which might have created them, and conclude with suggestions for further research.     

Potential misidentification of in situ archaeological tool-residues: starch and conidia

Microscopic identification of organic residues in situ on the surface of archaeological artefacts is an established procedure. Where soil components morphologically similar to use-residue types exist within the soil, however, there remains the possibility that these components may be misidentified as authentic residues. The present study investigates common soil components known as conidia, fungal spores which may be mistaken for starch grains. Conidia may exhibit the rotating extinction cross under cross-polarised light commonly diagnostic of starch, and may be morphologically indistinguishable from small starch grains, particularly at the limits of microscope resolution. Conidia were observed on stone and ceramic archaeological artefacts from Honduras, Palau and New Caledonia, as well as experimental artefacts from Papua New Guinea. The findings act as a caution that in situ analysis of residues, and especially of those less than 5 μm in size, may be subject to misidentification.     

遗址博物馆内土遗址本体可溶盐和霉菌危害预防与治理的进展

在博物馆建筑的保护下,尽管避除了由于风蚀、雨淋、日晒等有害因素所导致的土遗址裂隙、崩塌等病害现象,但是可溶盐迁移及霉菌滋生导致的表层风化等一系列危害会造成土遗址本体破坏和信息损失 ,所以进行这方面的研究尤其重要且迫切。本文主要综述了可溶盐、霉菌的破坏作用、产生原因、影响因素、防治措施等,并探讨了遗址博物馆内土遗址防治可溶盐及霉菌危害的可行性保护研究方法。     

书画上“狐斑”成因研究

中国书画所用的宣纸上常常会出现黄褐色的斑点“狐斑”。为探讨“抓班”的成因,通过对这些斑点的紫外光检测,pH检测,糖、有机酸、氨基酸含量分析,AES、SEM—EDS金属元素分析,黄褐斑纸片的培养,SEM观察等表明,从宣纸样品上的“狐斑”区与非“狐斑”区在金属元素铁、铜的含量无明显差别;在“狐斑”区培养出黄褐色的菌丝和孢子,并且从菌的分离、接种、再培养出现了黄褐色水珠;有机酸、氨基酸含量在“狐斑”区的异常等等结果,有充分理由证明宣纸样品上的“狐斑”与菌有关。这些菌有多种形态,其中二种菌当属曲霉属、青霉属。长有“狐斑”的宣纸酸度增加,纸张纤维素酸性水解的危险增大,这对书画的保护非常不利。“狐斑”问题必须加以足够重视。     

藏文大藏经金色经文成分及纸张微生物分析

藏文大藏经是翻译成藏文的印度佛教原典和佛教著述的总集,具有很高的历史价值、科学价值和艺术价值。本工作利用光学显微镜观察、扫描电子显微镜与能谱法、显微激光拉曼光谱法、高效液相色谱-质谱法、微生物分离纯化培养技术、分子生物学鉴定技术和高通量测序等方法分析了一件甘肃武威市博物馆藏书写金色经文的明清时期藏文大藏经样品和两件表面附有微生物的大藏经样品。分析结果表明:金色书写材料为金银铜合金颗粒,其中金(Au)含量72.8%～75.6%,银(Ag)含量22.8%～26.0%,铜(Cu)含量1.2%～1.6%,使用的金泥纯度不高;大藏经纸张用靛青染色,并以石墨涂覆表面;纸张的pH值在7.0～7.5之间,未酸化;纸张纤维间散布有大量真菌孢子,保存期间微生物繁殖生长的分泌物是纸张粘连的主要原因之一。纯化培养及分子鉴定结果表明大藏经表面绿色霉斑为烟曲霉(Aspergillus fumigatus),高通量测序结果显示附着在大藏经表面的微生物种类包括毛壳菌属(Chaetomium sp.)、曲霉属(Aspergillus sp.)、毛霉属(Mucor sp.)和白僵菌属(Beauveria sp.)等。研究结果可为大藏经保护材料和修复技术的选择提供信息与依据,也为其揭展和防霉材料筛选提供评估数据。     

志丹苑元代水闸遗址霉菌及防霉剂抑菌效果的再调查与评估

志丹苑元代水闸遗址中处于潮湿环境条件下的木构件经IPBC(碘代丙炔基氨基甲酸酯Iodopropy-nyl Butyl Carbamate)处理已有8年,2012年时测得其细菌总量及真菌总量比2007年分别减少89.25%和55.56%,且木构件中微生物主要类群也在变化。可近年发现IPBC药物的药效在缩短,为了更加有效地治理志丹苑元代水闸遗址饱水木构件上生长的霉菌,对遗址木构件霉菌种类再次进行调查,并对防霉剂IPBC抑菌性能进行再评估。本研究从遗址木构件中分离到8类高丰度霉菌,通过菌落形态特征、培养特性和DNA-ITS序列分析等方法进行菌种的鉴定,发现种类与前几次有明显不同。例如,本次在遗址广泛分布着的一种盘菌科下未分类的菌及绿色木霉都是前几次未曾发现过的。用滤纸片抑菌圈法对这些菌进行IPBC抑菌试验。分析结果发现,木质文物霉菌的防治药物有待升级。     

Reburial of shipwrecks in marine sediments: a long-term study on wood degradation

Historical shipwrecks in marine environments are continuously decomposed by wood-degrading organisms, adapted to this specific environment. To protect the wrecks from degradation and to preserve the unique remains for future generations, reburial of wrecks using various covering materials has been suggested as a long-term preservation method. The following experiment was carried out to study the bio-protective effect of sediment. Sound oak, pine, and birch samples were buried above and within marine sediment in Marstrand harbour, and retrieved for analysis after 6, 12, 24, and 36 months. Macroscopic as well as light-microscopic examinations were carried out on each occasion. Marine borers (shipworm, Limnoria), soft rot and tunnelling bacteria were wood degraders immediately above the seabed; soft rot, tunnelling bacteria, and erosion bacteria were active 10 cm below the seabed; erosion bacteria were the only degraders at a depth of 43 cm below the seabed. The wood species had different durability towards the decay agents. After 3 years, wood samples above the seabed were totally decomposed, whereas wood was highly protected at 43 cm depth in sediment. In the sediment, decay decreased significantly with depth of burial. The results suggest that reburial of shipwrecks in marine sediment can be recommended as a simple and efficient method for long-term preservation of the wooden cultural heritage.