Observacions sobre les algues edàfiques del delta del riu Ebre

Abstract

A study of the algae from the soils bordering marshes and fields sown with rice of the surrounding area of the delta of the Ebro river was performed. The counts with the suspension-dilution method gave values from 0 to 1.110 for the number of viable cells per gram of soil. We have identified 118 taxa, which correspond to 70 Cyanophyceae, 40 Chlorophyceae and 8 Xanthophyceae. We used the enrichment cultures for the isolation of species. The algae from the studied area presented a slow growth compared to that of the cultures of soils from similar ecosystems. This fact, together with the low number of cells per gram of soil, is ascribed to the herbicides used in the neighbouring cultivated fields.