Nervión River Estuary E1 Southern Bay of Biscay Latitude:   43.3494     Longitude:   -3.0264 Associated Investigators: Emma Orive , Javier Franco ,   Aitor Laza-Martinez ,   Sergio Seoane ,   Alejandro de_la_Sota ,   Marta Revilla   Related Web Sites: [Universidad del Pais vasco/Euskal Herriko Univertsitatea]   [Azti-Tecnalia]   [consorcioa de Aquas Bilbao-Bizkaia]   Related Time Series: [ Nervión Estuary E1 ]   [ Nervión Estuary E2 ]   The Nervión River estuary (also named Nervión-Ibaizabal estuary) has been monitored for phytoplankton taxonomic composition and abundance since 2000. The Nervión catchment is densely populated, and this study forms part of a broader monitoring programme performed to follow the water quality evolution after the implementation of a sewerage scheme in the area (Garcia-Barcina et al., 2006). Phytoplankton samples are taken aproximately monthly from March to September at eight stations (1-8, from the outer to the inner estuary) located along the longitudinal axis. Samples are analysed for cell identification and counted with the Utermohl method; in addition, individuals from selected genera among those forming blooms or known to contain harmful species are isolated from live samples and grown in cultures for a more detailed morphological and genetic characterization. Stations 1 and 2 are located in the outer estuary (Abra of Bilbao), which, with a width of ca. 3 km and a maximum depth of ca. 30 m, contains most of the estuarine water. This estuarine area is dominated by marine water during most of the monitoring period and phytoplankton species are mainly of marine origin.