Periphyton are those microalgae that grow on the benthic areas of a salt lake. They may be sampled by collecting materials that are immersed in the lake (rocks, large woody debris, sections of benthic mat communities) and scrubbing the coating microalgae off the surfaces for microscopic examination. Alternatively, artificial substrates may be placed into the lake for a period to be colonised by periphyton. The latter approach tends to produce a cleaner sample, which simplifies the process of identification.
Amongst the periphyton you are likely to commonly find diatoms, foraminifera, and colonial cyanobacteria. The last of these three form benthic mat communities in the base of shallow salt lakes and are discussed in more detail in a separate chapter. Diatoms occur through a very wide range of salinities and the persistence of their silica tests in the sediments of lakes allows for historic variations in salinity to be estimated.