Distribution of the bloom-forming diatom Didymosphenia geminata in the Ebro River basin (North-East Spain) in the period 2006-2009

Abstract

* Corresponding author Abstract This paper presents the distribution and the ecological parameters of Didymosphenia geminata in the Ebro River basin (Northeast Spain) during the period 2006-2009. The presence of blooms in some rivers in 2009, as in Cinca River in Las Pilas bridge, is reported. D. geminata was found in summer at 24 localities, forming blooms in three of them. It prefers mountainous calcareous rivers, regulated or not, with oligotrophic waters, low flow conditions and well illuminated stretches. In order to prevent nuisance blooms of the species, it is necessary to study its ecology and establish a monitoring network for detecting early stages of blooms in order to take control measures.