E4 DO [mg l-1]

May 1982 April 1983
Depth [m]  Jan    Feb    Mar    Apr    May    Jun    Jul    Aug    Sep    Oct    Nov    Dec
 Surface   5.2    4.8    5.0    5.8    5.5    6.0    5.0    6.5    4.8    4.8    5.2    5.0