Biological colonisation of stone is one of the main problems related to monumentsand buildings conservation. It is amply recognised that microalgae have the greatestecological importance as pioneer colonisers of stone materials, conducting to aesthetic,physical and chemical damages. Their deterioration potential is related with theirphotoautotrophic nature, using the mineral components of stone substrates and sunlight asenergy source without any presence of organic matter.Stone biodeterioration by microalgae has been assessed by several authors. Most ofthe employed methodologies for microbial identification and monitoring are timeconsumingand require extensive sampling. In addition, the scaffolding and samplingprocedures required may also transform the researcher in a biodeteriorating agent itself.In this chapter, non-contact techniques for colonisation detection and monitoring areproposed in order to fulfil the mission of heritage preservation. In vivo chlorophyll afluorescence and digital image analysis were applied to estimate microalgal biomass and to quantify coverage of limestone samples artificially colonised by algal communities.The results showed that Ançã and especially Lecce limestones were extensively colonisedon their surfaces revealing significant epilithic growth, whereas Escúzar and SanCristobal limestones were endolithically colonised by photoautotrophic microorganisms.The easily handled, portable and non-destructive techniques proposed allow theunderstanding of stone biodeterioration processes avoiding contact and damaging of theobjects, which ensures a wide field of application on cultural heritage studies and thedesign of appropriate conservation and maintenance strategies.
|Title of host publication||Microalgae: Biotechnology, Microbiology and Energy|
|Place of Publication||New York|
|Publisher||Nova science publishers|
|Publication status||Published - 1 Jan 2012|