Microscopic organisms are the key component in the formation of bioconcrete, as they provide the nucleation site for CaCO3 to precipitate on the surface.[1] Microorganisms such as Sporosarcina pasteurii are useful in this process, as they create highly alkaline environments where dissolved inorganic carbon (DIC) is present at high amounts.[29][failed verification] These factors are essential for microbiologically induced calcite precipitation (MICP), which is the main mechanism in which bioconcrete is formed.[3][26][29][30] Other organisms that can be used to induce this process include photosynthesizing microorganisms such as microalgae, cyanobacteria, and sulphate reducing bacteria (SRB) such as Desulfovibrio desulfuricans.[27][31]