Evaluation of three preparation methods for living diatoms at a sandy river-mouth tidal flat: conventional acid-cleaning, nuclear staining, and sieving

Three preparation methods for the identification of diatom flora at a river mouth tidal flat were evaluated in terms of species richness, diversity, and composition using a conventional acid-cleaning method, a nuclear staining method, and a newly introduced sieving method. Twenty-five diatom samples were collected from Fujimae Tidal Flat sediments, Nagoya, Japan, in July 2014. Three methods respectively showed different aspects of the diatom flora. The acid-cleaning method indicated the highest species diversity, but it extracted dead diatoms with living ones indiscriminately. In comparison with the acid-cleaning method, the staining method effectively extracted diatoms with fragile and small-sized cells. The sieving method scraped the sessile diatoms selectively and supplemented the staining method in which sessile diatoms were mostly neglected. A combination of these three methods enables to describe precise diatom flora of a tidal flat.