Fig. 5

Nitrate concentrations plotted as a function of phosphate (a) and silicate (b), and silicate concentrations plotted as a function of phosphate (c), of all samples collected in 1993.

Nitrate concentrations plotted as a function of phosphate (a) and silicate (b), and silicate concentrations plotted as a function of phosphate (c), of all samples collected in 1993.