摘要
南越国木构水闸遗址及其附属东汉建筑基址中的木构文物出现了多种病害。为探讨病害成因,采用偏光显微观察、傅里叶变换红外光谱分析、离子色谱分析和X射线衍射分析等技术方法对木构文物、积水和盐结晶等样品等进行检测,勘察文物病害种类与分布范围,并对环境监测数据进行多元回归分析。偏光显微镜观察到木构文物具有水松的显微特征,细胞壁多有细菌腐蚀;红外光谱分析发现半纤维素的特征峰消失,纤维素、木质素的特征峰锐减或改变;盐结晶的红外光谱、X射线衍射图谱均呈现二水合硫酸钙的特征峰,而离子色谱检测证实Ca^(2+)和SO_(4)^(2-)是积水的主要离子,表明两种离子随地下渗水迁移至文物表面并形成盐结晶;西部木材含水率(上)、西部木材含水率(下)和南部木材含水率(上)与地下水位均呈极显著正相关(P<0.01),木材含水率大多低于30%并不断变化。以上结果表明,地下水不但渗入文物造成饱水病害,同时也影响木材含水率的变化。当木材含水率低于30%时,文物纤维出现湿涨干缩并导致裂隙病害,过高时又促使细菌滋生而形成微生物损害。此外地下水带来的盐结晶也进一步加剧裂隙病害的发育。在多种病害的共同破坏下,木构文物最终形成残缺。该结果为文物后续的保护研究及保护工程的开展提供了重要的科学依据。
Wooden cultural relics from the Archaeological Site of the Wooden Watergate of Nanyue Kingdom and the Eastern Han Dynasty foundation site thereon have suffered from a variety of diseases.To investigate the contributing factors of these diseases,different methods(polarized light microscopy,Fourier transform infrared spectrometry,ion chromatography and X-ray diffraction)were employed to test and analyze the relics,stagnant water and salts.Disease surveying and environmental monitoring were implemented as well.The microscopic characteristics of the relics indicated that the wood was from Glyptostrobus pensilis(Chinese swamp cypress)and that the cell walls had been corroded by bacteria.The FT-IR spectra show that the characteristic peak of hemicellulose had disappeared and those of cellulose and lignin had diminished or become degenerative.The salt crystals were raw plaster demonstrated by the FT-IR and XRD results,and Ca^(2+)and SO_(4)^(2-)were the dominant ions in the stagnant water as confirmed by ion chromatography,which illustrated that the ions had migrated to the relic surface with seepage and turned to salts.There was a significant positive correlation(P<0.01)between the groundwater and the level wood moisture content in the western region(top),western region(bottom)and south region(top).The wood moisture contents were mostly lower than 30%and kept changing.All the above results indicate that groundwater had not only infiltrated into the relics to cause wetting,but also affected the change of wood moisture content.When the wood moisture content was lower than 30%,the wooden fibers would swell and shrink leading to fissures,but being excessively high would promote the breeding of bacteria,leading to microbial damage.Salts brought by groundwater further exacerbated the development of fissures.Eventually,affected by all the above diseases,the relics rotted away in part.This study provides a theoretical support for the subsequent conservation and restoration of the relics.
作者
韩炜师
HAN Weishi(Guangzhou Municipal Institute of Cultural Heritage and Archaeology,Guangzhou 510006,China)
出处
《文物保护与考古科学》
北大核心
2024年第4期118-127,共10页
Sciences of Conservation and Archaeology
基金
国家文物保护专项资金资助(191024400003)
广东省文化繁荣发展资金资助(20190618400313)。
关键词
水闸
木构文物
保存状况
病害
环境监测
Watergate
Wooden cultural relics
State of preservation
Disease
Environmental monitoring
