Characterizing the Microbial Colonization of a Dolostone Quarry: Implications for Stone Biodeterioration and Response to Biocide Treatments

Abstract

This study examines the microbial colonization of three fronts of an abandoned dolostone quarry (Redueña, Madrid, Spain) exposed to atmospheric conditions for different time periods since Roman times to the present. Through scanning electron microscopy in backscattered electron mode (SEM-BSE), endolithic colonization was predominantly detected in the most recently exposed front, while in the longer exposed quarry fronts, epilithic forms of growth were most often observed. These observations were confirmed by denaturing gradient gel electrophoresis (DGGE) analysis. Based on the distribution pattern of microbial colonization in the different quarry fronts, we then established a sequence of colonization events that took place over this long time frame. Bioalteration processes related to this sequential colonization were also identified. Characterizing these sequential processes can be useful for interpreting biodeterioration processes in historic dolostone monuments, especially those affecting constructions in the area of the Redueña stone quarry. In a second experimental stage, different biocide treatments were tested on this quarry rock to find the best way to avoid the microbial colonization effects identified. Through combined SEM-BSE/DGGE analysis, the efficacy of several biocides against the microorganisms inhabiting the dolostones was assessed after 4 and 16 months treatment. In general, all treatments were effective at reducing around 80% of the lichen cover, although effects on endolithic lithobiontic communities were dependent on how well the rock surface had been mechanically cleaned prior to treatment and gradually disappeared over time.

Differential Colonization and Succession of Microbial Communities in Rock and Soil Substrates on a Maritime Antarctic Glacier Forefield

“…Consistently with other non-polar dryland habitats (Lee et al, 2016), pioneering studies in Antarctica suggested that the edaphic and lithic niches differed in microbial community composition (Pointing et al, 2009;Makhalanyane et al, 2013;Yung et al, 2014;Van Goethem et al, 2016). Evidence based on the rock colonization rate after biocide treatments suggests that changes in lithobiontic communities may occur even over short periods of time (Cámara et al, 2011), but how these differences are established and evolve over time for different types of microorganisms remains unexplored.…”

Assessment of Paint Layers Quality 2. Identification of biological species grown on a railway bridge

“…In these conditions, the prevention of biofouling growth can be achieved either by the selection and application of high resistance coating materials to natural thermooxidative processes (thermal stress and UV action [6,13,14,16] and the molds action [8,10,15]), or through the use of appropriate antifungal biocides [35][36][37][38][39][40][41] (obviously with the necessary precautions -taking into account that the investigated bridge is in the Natura 2000 protected area [24]).…”

Infrared and ultraviolet laser removal of crustose lichens on dolomite heritage stone

“…Remediation protocols for stone degradation by biological attack include the use of biocides or sterilization by UV light, but their effect is often limited to the surface of the material treated [16][17][18] and, in the case of biocides, irreversible damaging side effects may be induced on the rock materials.…”