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尽管外部营养盐的输入量下降了约30%,但在芬兰湾的开阔海区并没有出现相应的改善。20世纪90年代末向芬兰湾中的氮排放量达到了每年120000t,而每年磷的排放量为7000t。就其表面水域而言,芬兰湾海区营养盐的单位面积排放量是整个波罗的海营养盐平均单位面积排放量的2～3倍。尽管排放量有所下降,但在20世纪90年代中期海表和近海底的水域中磷酸盐的浓度仍呈上升趋势。导致这种状况发生的主要原因可能是20世纪90年代芬兰湾东部海域沉积物与水的交界处氧气状况的恶化导致了内部营养盐排放的增多,但20世纪80年代和90年代初期这一海区的供氧状况相对较好。根据在芬兰湾近海获取的实验数据,表层沉积物和水之间的磷酸盐-磷的通量已减少到平均值,13kg/km~2·d。这与在波兰湾开阔海区测量到的能够代表其变化趋势的磷含量相符。沉积物流出物中氮和磷的低比率在一定程度上解释了芬兰湾的初级生产中氮受到的限制。
Although the input of external nutrients has dropped by about 30%, no corresponding improvement has taken place in the open sea in the Gulf of Finland. Nitrogen emissions to the Gulf of Finland at the end of the 1990s reached 120,000 tons per year, while annual phosphorus emissions were 7,000 tons. In terms of surface waters, the discharge of nutrients per unit area of the Gulf of Finland is 2-3 times the average discharge per unit area of the Baltic Sea nutrient. Despite declining emissions, phosphates concentrations in sea-waters and offshore waters still showed an upward trend in the mid-1990s. The main reason for this may have been the worsening of the oxygen situation at the junction of sediment and water in the eastern Gulf of Finland in the 1990s, leading to an increase in nutrient discharge inside, but in the 1980s and early 1990s, The oxygen supply is relatively good. Based on experimental data obtained off the coast of the Gulf of Finland, the flux of phosphate-phosphate between surface sediments and water has been reduced to an average value of 13 kg / km ~ 2 · d. This is in line with the measured phosphorus content in open sea areas in the Polish Gulf that represents its changing trend. The low N and P ratios in sediment effluents explain to some extent the limitation of nitrogen exposure in primary production in the Gulf of Finland.