COMPARISON OF 2 METHODS FOR TOTAL PHOSPHO RUS DETERMINATION IN SEAWATER (PERSULFATE DIGESTION BY KOROLEFF-VALDERRAMA AND DIGESTION WITH MAGNESIUM-NITRATE)

Comparative studies have been undertaken on different methods for dete rmination of total phosphorus by persulfate oxidation (Koroleff and Vo lderrama) and magnium nitrate oxidation. It is found out that the seaw ater and the intersticial water with the concentrations of total phosp horus less than 0.5 muM are characterized by variations of oxidation r esults from different methods no were than 3 - 5%. The increase of tot al phosphorus content couples with the growth of descrepancy in oxidat ion results. Still, it makes less than 20% even for the ligh-productiv e waters of the Bering Sea. We hold unreasonable to give up a rutine m ethod of Koroleff-Volderrama for the determination of total phosphorus . The use of vacuum evaporator increases the representativity of the m ethod with the magnium nitrate.