Академическое издательство «Гео»

Keywords: river channel transformation, channel processes, siltation, melioration, ponds, channel dynamics.


Formation of small river
channels of the Volga Upland in conditions of centuries-long agricultural development

R.S. Chalov*, D.V. Botavin*, A.L. Varenov**, A.S. Zavadskii*, A.M. Tarbeeva*

*Lomonosov Moscow State University, 119991, Moscow, Leninskie gory, 1, Russia,
rschalov@mail.ru, dmitry.botavin@gmail.com, az-mgu@mail.ru, amtarbeeva@yandex.ru
**Koz’ma Minin Nizhni Novgorod State Pedagogical University,
603950, Nizhni Novgorod, ul. Ulyanova, 1, Russia, balagur332geo@yandex.ru

On the basis of comparing old maps, satellite imagery and archival material, interviewing local residents and doing fieldwork, we reconstructed the history of agricultural development of the small river Kud’ma basin on the Volga Upland over the last 150–200 years and assessed its influence on the transformation and modern dynamics of small river channels. We developed the zoning scheme for the basin according to three types of anthropogenic impact on the channels, the directedness of vertical deformations and to corresponding channel transformations. It is shown that the character of channel transformation depends on the natural differences of the rivers within the basin as well as on the specific practices of using the different-order rivers and on the character of development of different parts of the basin as a whole. It is found that the largest impacts on the channels that led to a change of the morphodynamic type of channel and to the transformation of the floodplain to the terrace occurred in the middle reaches of the main rivers, Kud’ma and Ozerka: a large-scale channel rectification was organized on the Kud’ma river, whereas the channel incision on the Ozerka river was caused by draining the ponds in the 1930s. Changes in the channel morphodynamics was also manifest in the character of straightening of meanders and the formation of specific lake-like expansions at their heads. A serious transformation occurred in the channels of the smallest rivers in the developed part of the basin which were affected by siltation. Feedbacks occurring in the case of impacts on the river are demonstrated: channel rectification with the purpose of draining swampy floodplains for agriculture leads, because of the channel incision, to a shortage of water resources and dictates a need for land irrigation.

Keywords: river channel transformation, channel processes, siltation, melioration, ponds, channel dynamics.

DOI: 10.21782/GIPR0206-1619-2018-3(86-94)