Chemical Degradation of Wooden Components in Traditional Dwelling No. 9, East Gate Lane, Gulian Village: Assessed by Polarized Light Microscopy, Fluorescence Microscopy, and Histochemical Staining

Abstract

To accurately elucidate the microscopic degradation characteristics and deterioration mechanisms of wooden components in traditional northern Chinese dwellings, this study investigated wooden components retrieved from the Ming-Qing residential building at No. 9, East Gate Lane, Gulian Village, Qi County, Shanxi Province. Polarized light microscopy, fluorescence microscopy, and histochemical staining techniques were employed to qualitatively assess the degradation degrees of cellulose and lignin in six wood species: elm, poplar, willow, birch, Chinese larch, and Chinese pine. Internal and external deterioration drivers were analyzed, and corresponding conservation strategies were proposed. The results showed that all tested wooden components exhibit moderate to severe chemical degradation. The deterioration of wooden components is synergistically driven by interspecific differences in natural decay resistance, rainwater erosion, ultraviolet radiation, building structural damage, and microbial infestation. Elm components are mainly attacked by white-rot fungi, while the other wood species are predominantly affected by soft-rot fungi. Poplar and willow are more susceptible to insect damage. This study provides a scientific basis and technical support for the microscopic diagnosis, precise restoration, and preventive conservation of Ming-Qing wooden architecture in the Jinzhong region.