4.10 4 Nutrient supply by rivers4.8 4.9

4.9

Time-averaged runoff and riverine export of NO3-N, total-N, PO4-P and total-P to the major sub-basins of the Baltic Sea. The selected rivers are the ten largest in the Baltic Sea drainage basin. Study period: 1980-1993. Source: Stålnacke, P., Grimvall, A., Sundblad, K. and Tonderski, A. 1999. Estimation of riverine loads of nitrogen and phosphorus to the Baltic Sea, 1970-1993. Environmental Monitoring and Assessment 58: 173-200.  

Baltic Sea sub-basin/river Runoff NO3-N total-N PO4-P total-P
  109 m3 yr-1 tonnes yr-1 tonnes yr-1 t yr-1 tonnes yr-1
Gulf of Bothnia        
Kemijoki 18.9 1 100 6 900 140 420
Lule R. 16.7 560 3 300 40 180
Ångermanälven R. 17.1 890 4 650 35 200
Indalsälven R. 15.3 1 390 4 540 25 140
Other monitored rivers 11.5 15 980 60 250 1020 3250
Non-monitored rivers 24.3 7 960 20 750 610 1 220
Subtotal 103.8 27 880 100 390 1870 5 400
Gulf of Finland
Neva R. 81.7 21 260 55 590 1 200 3 210
Narva R 14.3 4 010 26 400 290 750
Other monitored rivers 18.5 11 830 17 110 550 660
Non-monitored rivers 7.7 8 620 26 870 560 1 510
Subtotal 122.2 45 720 125 970 2 600 6 130
Gulf of Riga
Daugava R. 23.3 28 680 70 130 970 1 330
Other monitored rivers 9.7 21 480 35 940 450 670
Non-monitored rivers 3.3 4 120 7 160 90 240
Subtotal 36.3 54 280 113 230 1 510 2 240
Baltic proper
Neman R. 20.5 31 650 58 3401 4 140 5 410
Vistula R. 32.4 59 280 119 080 3 570 5 510
Oder R. 16.3 41 900 71 430 2 510 6 630
Other monitored rivers 19.9 18 760 36 430 900 1 340
Non-monitored rivers 23.9 41 410 77 740 2 100 4 300
Subtotal 113.0 193 000 363 020 13 220 23 190
Western Baltic
Göta R. 18.0 10 080 16 250 60 300
Other monitored rivers 11.4 47 620 57 210 880 1 860
Non-monitored rivers 8.0 38 980 49 830 1 110 2 040
Subtotal 37.4 96 680 123 290 2 050 4 200
Total Baltic Sea 412.7 417 560 825 900 21 250 41 160


4.10 4 Nutrient supply by rivers4.8 4.9