Mat thickness associated with Didymosphenia geminata and Cymbella sp. in the southern rivers of Chile

Didymosphenia geminata is a diatom that can alter aquatic systems. According to the international literature, chemical and hydraulic factors have a greater influence on the proliferation of D. geminata , but the study of other microalgae that could be associated with it has been poorly addressed. The objective of this study is to evaluate the relationship between the structure of mat thickness D. geminata and another taxon that produces mucilage, Cymbella sp. , while also considering physical and chemical factors. To do this, two samples were taken, one in the spring of 2013 and the other in the autumn of 2014, from eight rivers in central-southern Chile-South America, where the benthic community was characterized and the thickness of the mat was measured. The results indicate that in the presence of both taxa the thickness of the mat layer is doubled. However, antecedents suggest that D. geminata is the main producer of mucilage, being seconded by Cymbella sp. The present study contributes evidence about the relationship between mat thickness D. geminata and other microalgae contribution, and aquatic condition for this development.