An overview of the literature concerning the oceanography of the eastern North Atlantic region

An overview of the main oceanographic features of the eastern North Atlantic boundary, with emphasis toward the upper layers, is presented. The principal features discussed are: water mass boundaries; forcing by wind, density and tides; topographic features and effects; fronts; upwelling and downwelling; poleward flows; coastal currents; eddies. The occurrence and spatial and seasonal variability of these features is described in five regional sections: Celtic Sea and western English Channel; Bay of Biscay; western Iberia; Gulf of Cadiz; northwest Africa. This paper is intended to provide a base of physical oceanographic knowledge in support of research in fisheries, biological and chemical oceanography, and marine biology.

Atmospheric pressure chemical ionisation liquid chromatography/mass spectrometry of the ultraviolet screening pigment scytonemin: characteristic fragmentations

Atmospheric pressure chemical ionisation reversed-phase high-performance liquid chromatography/multistage mass spectrometry has been used to study the mass spectral fragmentation of the cyanobacterial sheath pigment scytonemin and its reduced counterpart. The two pigments exhibit characteristic fragment ions in their MS2 and MS3 spectra that are of value in confirming the identification of the structures in extracts from natural environments.

Ecological equivalence of species within phytoplankton functional groups

1.There are tens of thousands of species of phytoplankton found throughout the tree of life. Despite this diversity, phytoplankton are often aggregated into a few functional groups according to metabolic traits or biogeochemical role. We investigate the extent to which phytoplankton species dynamics are neutral within functional groups. 2.Seasonal dynamics in many regions of the ocean are known to affect phytoplankton at the functional group level leading to largely predictable patterns of seasonal succession. It is much more difficult to make general statements about the dynamics of individual species. 3.We use a 7 year time-series at station L4 in the Western English Channel with 57 diatom and 17 dinoflagellate species enumerated weekly to test if the abundance of diatom and dinoflagellate species vary randomly within their functional group envelope or if each species is driven uniquely by external factors. 4.We show that the total biomass of the diatom and dinoflagellate functional groups is well predicted by irradiance and temperature and quantify trait values governing the growth rate of both functional groups. The biomass dynamics of the functional groups are not neutral and each has their own distinct responses to environmental forcing. Compared to dinoflagellates, diatoms have faster growth rates, and grow faster under lower irradiance, cooler temperatures, and higher nutrient conditions. 5.The biomass of most species vary randomly within their functional group biomass envelope, most of the time. As a consequence, modelers will find it difficult to predict the biomass of most individual species. Our analysis supports the approach of using a single set of traits for a functional group and suggests that it should be possible to determine these traits from natural communities.