Onuchin A. A. The Reasons for Conceptual Contradictions in Evaluating Hydrological Role of Boreal Forests

Abstract

How to cite: Onuchin A. A. The reasons for conceptual contradictions in evaluating hydrological role of boreal forests // Sibirskij Lesnoj Zurnal (Siberian Journal of Forest Science). 2015. N. 2: 41–54 (in Russian with English abstract).

DOI: 10.15372/SJFS20150204

© Onuchin A. A., 2015 

The paper attempts to resolve contradictions in the evaluation of the hydrological significance of the boreal forest. The article focuses on the study of the hydrological cycle mainly at the local level in connection with the specificity of vegetation and background of climate. It is stated that the ratio between evaporation and runoff in the warm season is mainly determined by the productivity of land, and less by the type of vegetation, whether forests or other types of land. This effect is due to the fact that the root systems of large trees act as "powerful submersible pumps", evaporating moisture including from the lower soil horizons. In the cold season, when precipitation falls as snow and is permanently preserved in the snow cover, the intensity and direction of the flow of water is not associated with the productivity of vegetation, and is mainly determined by the type of vegetation (forest, treeless space) and by environmental conditions. It is argued that the ambiguity of the impact of forests on the redistribution of precipitation between evaporation and runoff is due mainly features balance of the snow moisture, which is defined as the structure of the forest cover as well as the environment. Concepts of the geographically-determined hydrological role of forests are suggested. The results explain the contradictions in the hydrological role of forests (water consumption and water yield) and may be useful in the formation of land-use strategies in the regions where relationship problems of water resources and forest cover are relevant.