«MEANDER» AND «BEND» AS MORPHOLOGICAL UNITS OF PLANIMETRY OF A MEANDERING CHANNEL: AN ANALYSIS OF EXISTING CONCEPTS

The article is devoted to the description and comparison of two approaches used in the study of the planimetry of meandering channels by methods of hydromorphological analysis: the approach developed and widely used in the Soviet (Russian) school of channel process research, in which the bend is taken as the basic morphological unit of a meandering channel, and the approach in which the basic morphological unit is the meander – this approach it is more common in the works of foreign authors. It is shown that the first approach, which defines a river bend as a section of the channel between two successive inflection points of the channel centerline, allows for unambiguous identification of bends during the processing of cartographic materials. At the same time, the formulations used in the second approach, in most cases do not even allow for precise identification of the section of the channel defined as a meander. Moreover, within the second approach, there are two methods for defining a meander. One method defines a meander as a section of the channel between three successive inflection points of the channel centerline, while the other method defines it as a section between two consecutive apexes lying on one side of the axial line of the meandering belt. Given the increasing use of semi-automated and automated procedures in conducting of hydromorphological analysis, it is becoming increasingly important to accurately identify the objects being analyzed. Therefore, the concept of «bend» seems to be more certain, technologically advanced and reliable than the concept of «meander». So, when conducting morphometric analysis and searching for patterns in the plan configuration of meandering channels, it would make sense to rely primarily on the approach that uses the bend as the main morphological unit.

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