5. Biogeochemical Basis of Construction Bioprocesses

The chemical reactions and physical processes of biogeochemical cycles of carbon, nitrogen, calcium, magnesium, phosphate, iron, silicon are used for the construction bioprocesses. Microbial oxygenic photosynthesis can be used in construction biotechnology for the formation of soil crust to control dust release, to stop sand dunes movement, and to immobilize atmospheric dispersion of soil surface pollutants, for example radioactive substances. Microbial anoxygenic photosynthesis could be used in construction biotechnology for the removal of H₂S from water or from biorestoration of marble historical sculptures or constructions deteriorated by the black precipitate of CaS produced by bacterial sulfate reduction of sulfur oxides from polluted air. Acidogenic fermentation could be used in construction biotechnology for the production of organic (mainly acetic) acid and dissolution of calcium carbonate, magnesium carbonate, or iron (hydr)oxide with the formation of soluble salts of Ca, Mg, and Fe. Urease-inducing or aerobic oxidation of calcium salts of organic acids can be used further for bioaggregation, bioclogging, and biocementation of porous soil or fractured rocks due to calcium carbonate precipitation. Oxidation of ammonium to nitric acid is one of the important factors of biocorrosion of metals and biodeterioration of concrete and marble. Biomediated formation of carbonate, phosphate, and silicate minerals of calcium, iron, and magnesium is the prospective way for production of construction materials and the performance of the construction processes. Some of them are used in construction but many of these potentially useful bioprocesses were not discovered and studied yet.