Estimation of variability of the ratio of total nitrogen and total phosphorus concentrations in marginal filters of tidal estuaries of the White and Barents seas

It was revealed that the parameter Ntot/Ptot in the tidal mouths of the rivers of the western sector of the Russian Arctic tends to increase in the zone of the biological stage of the marginal filter as it approaches the waters of the open waters of the sea. Here, the concentrations of total nitrogen in dissolved form clearly exceed the concentrations of total phosphorus, approaching their ratio determined for their mineral salts. Minimum parameter Ntot/Ptot is observed in the zone of the coagulation-sorption stage of the marginal filter, but in the mouths of some small rivers it can also be observed in the zone of the gravitational stage. Here, the concentrations of total phosphorus can reach the level of total nitrogen or even exceed it. This situation is apparently related to the peculiarities of the spatial distribution of boundary surfaces (water-coast, water-bottom, water-macrophytes) in estuarine objects with the presence of tidal drylands.