Chemical Indication of the Processes of Freshet Runoff Formation in a Small Experimental Catchment in the Prilenskoe Plato, The Republic of Sakha (Yakutia).

The article considers the theory, methods, and some results of four-year field studies of the processes of runoff formation on a small freezing experimental river catchment in a continuous thick (400 m) permafrost zone (the Republic of Sakha (Yakutia)) based on data on natural water chemistry. The analyzed problems include the seasonal and daily dynamics of river flow in the warm season, the concentrations of some dissolved substances in different types of water, as well as the role of channel widenings, supra-permafrost water, and aufeises in flow formation. Various types of relationships between water discharges and the concentrations of some dissolved substances are described under varying hydrothermal conditions. The role of nonfreezing lake-like channel widenings (bochags) in the regulation of freshet flow of water and dissolved matter is evaluated. The efficiency of the automated digital registration of the level, temperature, and specific electric conductance of water with a high time resolution at hydrological gages is discussed, especially, as applied to the rapid processes in a river. [ABSTRACT FROM AUTHOR]