Soil diatom communities and their relation to environmental factors in three types of soil from four cities in central-west China

Abstract

Diatoms constitute a major part of microbial biomass and species richness in soil habitats. However, in spite of a growing interest on soil diatoms, variations in soil diatom communities across different types of soil are poorly known. We hypothesize that diatom communities are different in distinct soil types and can serve as a potential bioindicator for soil environmental assessment. Thirty-four soil samples were collected from Wuhan (yellow brown soil, n = 11), Xi'an (yellow cinnamon soil, n = 10), Korla and Karamay cities (brown calcic soil, n = 13) in central-west China. Diatom flora and thirteen environmental variables were analysed in these soil samples. In total, 66 taxa belonging to 30 genera were identified. Analysis of similarity (ANOSIM) revealed that diatom communities are significantly different among the three types of soil. The indicator species of yellow brown soil in Wuhan City included Pinnularia microstauron, Nitzschia amphibia, Sellaphora nigri, Pinnularia borealis and Humidophila contenta. Brown calcic soil in Korla and Karamay cities was characterized by Luticola suecorum, Luticola cohnii, Luticola nivalis and Luticola mutica. Yellow cinnamon soil in Xi'an City was featured by Stauroneis lundii and three unidentified Luticola species. Results of RDA showed that diatom communities were significantly correlated with magnesia, total phosphorus, organic phosphorus and conductivity, suggestive of the effects of nutrients and ionic strength on soil diatom distribution. Our results reveal high diatom diversity in soil habitats and highlight the potential of diatoms as a bioindicator for soil environmental assessment.