Oslo and Paris Commissions (OSPAR) Annual report in direct and riverine inputs to Norwegian coastal waters during the year 1997. A. Principles results and discussions B. Data report
Abstract
Riverine inputs of nutrients, selected heavy metals and persistent organic pollutants to Norwegian coastal waters from 10 main and 145 tributary rivers have been monitored during 1997. In addition, the inputs from rivers not monitored as well as direct discharges to marine waters along the coast from Sweden to Russia have been estimated. According to the results, total annual nutrient load to coastal waters from landbased sources, is approximately 3600 tonns of phoshorus and 101.600 tonnes of nitrogen. About 40 per cent of the phosphorus and 59 per cent of the nitrogen are inputs from the monitored rivers and tributaries. Most inputs of heavy metals are low, especially the riverine inputs of Cd, Pb and Hg. A few values of Cd and Pb are below the detection limits of the specific analysis, and about 45 % of the Hg-analyses except for the "Skagerrak-rivers", where about 70 % of the Hg-values are above the detection limit. Most values of the different congeners of PCB are below the detection limit. The pesticide lindane is detection in most analyses in small amounts. Total load of this compound is estimated to about 80 kg. The largest yields from heavy metals comprise copper and zinc, with input estimates of 326 and 902 tonnes, respectively. Retention in the fjords is not included in the above mentioned values, which in several cases would reduce the actual load to open marine waters considerably.