Nutrient concentration profiles from time series station E1 in the western English Channel in 2006

Nutrient samples for the analysis of nitrate, nitrite, silicate and phosphate for station E1 in the Western English Channel are taken fortnightly where the conditions allow it. They are sampled under clean conditions and returned in the cool and dark, and as soon as possible to the laboratory where samples are analysed for both for filtered (0.2 µm Millipore Fluoropore) and non-filtered water. Samples are not stored or frozen unless there are extenuating circumstances making the live analysis impossible. The analyser is a 5-channel Bran and Luebbe segmented flow system using well tested methodologies, and the same as those used by the PML nutrient group in all their International Research cruises, and research programmes. Quality control procedures are carried out using certified reference materials, and also the group participates in the Quasimeme programme. This has been the protocol since 2007, and prior to that the samples were stored frozen and then analysed in batches. The E1 samples are normally taken for the following depths: Surface, 10 m, 20 m, 30 m, 40 m and 60 m.