Abstract:
A range of fungal species showed variable abilities to colonize and penetrate a mortar substrate. Calcium biomineralization was a common feature with calcium-containing crystals deposited in the microenvironment or encrusting hyphae, regardless of the specific mortar composition. Several species caused significant damage to the mortar surface, exhibiting burrowing and penetration, surface etching, and biomineralization. In some cases, extensive biomineralization of hyphae, probably by carbonatization, resulted in the formation of crystalline tubes after hyphal degradation on mortar blocks, including those amended with Co or Sr carbonate. Ca was the only metal detected in the biomineralized formations with Co or Sr undetectable. Aspergillus niger, Stemphylium sp. and Paecilomyces sp. could penetrate mortar with differential responses depending on the porosity. Fluorescent staining of thin sections recorded penetration depths of ∼530 um for A. niger and ∼620 um for Stemphylium sp. Penetration depth varied inversely with porosity and greater penetration depths were achieved in mortar with a lower porosity (lower water/cement ratio). These results have provided further understanding of biodeteriorative fungal interactions with cementitious substrates that can clearly affect structural integrity. The potential significance of fungal colonization and such biodeteriorative phenomena should not be overlooked in built environment contexts, including radionuclide storage and surface decontamination.
摘要:
一系列真菌物种显示出不同的定殖和渗透砂浆基质的能力。钙生物矿化是含钙晶体沉积在微环境中或包裹菌丝的共同特征,无论具体的砂浆成分。几种物种对砂浆表面造成了重大损害,表现出挖掘和渗透,表面蚀刻,和生物矿化。在某些情况下,菌丝广泛的生物矿化,可能是通过碳化,导致在砂浆块上菌丝降解后形成结晶管,包括用Co或Sr碳酸盐修正的那些。Ca是在生物矿化地层中检测到的唯一金属,无法检测到Co或Sr。黑曲霉,茎phyliumsp.和拟青霉。根据孔隙率的不同,可能会以不同的响应穿透砂浆。薄切片的荧光染色记录了黑曲霉的渗透深度为530um,而茎phyliumsp.渗透深度与孔隙率成反比,在孔隙率较低(水灰比较低)的砂浆中实现了更大的渗透深度。这些结果提供了对生物变质真菌与胶结基质相互作用的进一步理解,这些相互作用可以明显影响结构完整性。在建筑环境中,不应忽视真菌定植和这种生物退化现象的潜在意义。包括放射性核素储存和表面净化。