埋葬土壤中阴离子含量分布特征及对金属文物的影响

Distribution characteristics of anion content in buried soil and its effects on metal relics

金属文物在埋葬土壤环境中腐蚀情况比较复杂,使得保护金属文物方面受到一定的限制。采用离子色谱法测定墓地土壤中水浸取液的F^-、Cl^-、SO4^2-和NO3^-的含量,探讨阴离子含量随土壤深度的分布特征及对金属文物的影响。结果表明,F^-、NO3^-含量随着深度的增加整体呈升高趋势;而SO4^2-、Cl^-作为腐蚀金属文物的主要阴离子,含量整体呈现出波浪状。其中SO4^2-含量在距地面3 m处达到最大,并且在5.5 m处又出现小峰值;Cl^-在距地面2 m左右出现小峰值,之后一直递增,在距地面5.5 m处含量达到最大。阴离子对金属文物的影响体现在地下环境使得金属与阴离子发生电化学反应,进而加速金属文物的腐蚀。阴离子对土质文物的影响主要表现在SO4^2-、Cl^-的破环性较强,这可能是由于地下环境的复杂使得土质文物出现酥碱、霉变等盐害。

The complex corrosion of metal cultural relics in the burial soil environment,the protection of metal cultural relics is subject to certain restrictions.Ion chromatography was used to determine the F-,Cl-,SO4^2- and NO3^- contents of the water extract in the soil of the cemetery.By exploring the distribution characteristics of anion content with soil depth,it is helpful to discover the relationship between metal cultural relics and anion content in the soil environment.The results showed that the F^- and NO3^- contents showed an overall upward trend with the increase of depth;As the main anions that corrode metal cultural relics,SO4^2- and Cl^- show a wave-like content overall.The SO4^2- content reaches the maximum at 3 m above the ground,and a small peak appears again at 5.5 m;the Cl^- shows a small peak at about 2 m above the ground,and then increases continuously,reaching the maximum at 5.5 m above the ground.The influence of anions on metal cultural relics is reflected in the underground environment,which makes the electrochemical reaction of metals and anions,which accelerates the corrosion of metal cultural relics.The impact of anions on soil cultural relics is mainly manifested in the strong destructiveness of SO4^2- and Cl^-,which may be due to the complexity of the underground environment that causes salt damage such as croak and mildew in soil cultural relics.