At the end of the 20th century the attention was focused on the regularities of variations in the natural properties of bogs subjected to drainage, the effect of drainage on the adjoining areas and water receivers, and the development of the landscape principles and engineering measures for the environmental protection. Under the conditions of the European North of Russia, agricultural and forestry drainage, which generally comprises <10% of the catchment area of the suo-rivers systems, has only a slight effect on the hydrological regime of these ecosystems.