Organic matter and mineralization of river waters in mountains of Russia and adjacent countries
The article examines general regularities of the formation of dissolved organic matter (DOM), salinity (∑), the acid-alkaline indicators (pH) river waters in the mountains with various types of altitudinal zonation in Russia and CIS countries. The analysis is based on the results of many years of experimental studies in the network of the Roshydromet. The reaction of water of rivers in a southerly direction in accordance with changes in landscape-geochemical conditions are sequentially changed from acidic in the tundra of the Arctic to neutral in the tundra and taiga, slightly alkaline in forest-meadow and alkaline in a desert and subtropical mountains. The average annual salinity water of the mountain rivers in two Northern types of vertical zones is 42 and 74 mg/l, in two Southern types - 140 and 450 mg/l. The average annual values of permanganate (PO) and bichromate (BO) oxidation, and color of river water in xerophytic desert-subtropical mountains are small (3 and 7), and increase to medium and slightly increased grades into humid tundra and taiga, tundra of the Arctic, and the forest meadow mountains (7-8 and 13-18 mg O/l). Relationships PO:BO change from 62% in the tundra of the Arctic up to 50%, 41% and 35% in the tundra and taiga, forest-meadow and desert-subtropical mountains. The content of humic (HA) and fulvic (FA) acids is also maximum in two Northern types of vertical zones (0.224 and 1.80 mg/l) and decreases in the two Southern types to 0.013 and 0.067, 0.373 and 0.637 mg/l. The relationship of contents of HA and FA decreases to the South in forest-grassland and desert-subtropical mountains in 1.3 and 3.7 times.