Seasonal fluctuations in nutrient concentrations, N/P ratio's and chl. A concentrations in the southern North Sea 1985-1986

The aims of this study are: -To assess the geographical distribution and seasonal fluctuations of the relevant nutrients for phytoplankton growth (N, P, Si) and chlorophyll a, during 1985 and 1986. -To determine the maximum ("winter") and minimum ("summer") nutrient concentrations, their seasonal variations, the (maximum) rates of decline in nutrient concentrations, all this in comparison with (the timing of) Chl. a maxima ("summer"), minima ("winter"), seasonal variations and the (maximum) rates of increase in Chl. a. - To examine the seasonal aspects for various relevant regions: coastal (southern, central, northern) zones (where the influence of various riverine nutrients inputs are expected to be high) and a southern transverse transect to the offshore zone. -To examine the use of nutrient concentrations and N/P ratio's as tools for assessment of algal growth-limiting factors.