Organic Matter Transformation in the Conjugate Series of Surface Water in Northern Karelia

Abstract

The composition of organic matter in the conjugated series of natural water (soil, bog, creek, and lake water) has been considered. The composition of aliphatic and aromatic carboxylic acids and humic substances has been determined. Humic substances have been found to account for the major portion of dissolved organic carbon (from 28 in lake water to 57% in bog water with weight-averaged molecular masses of the order of 1 kDa); and the amounts of aliphatic and aromatic carboxylic acids, to account for ≤2% of the total concentration of carbon of water-soluble organic compounds. Transformation of dissolved organic matter have been shown to take place in the series of the examined water: the composition and its characteristics have been shown to change; and the share of the fraction with molecular mass <1 kDa, to increase because of photo- and biodegradation of high-molecular organic compounds.