A model for ecosystem state and water quality management in the Dnieper River delta

Abstract

An ecologically sound management methodology for maintaining ecosystem state and water quality in regulated rivers downstream of hydropower stations is presented. The main components of this methodology are applied to the Dnieper River mouth zone as an example. The relationship between production–destruction (respiration) balance and releases through the Kakhovka hydropower dam has been determined for the channel network, floodplain lakes, the floodplain proper, and the Dnieper River mouth zone combined. Production–destruction processes are predicted as the change in organic matter content, as measured by BOD tot. We have developed calculation methods for ecosystem functioning and water quality management in the Dnieper River mouth zone channel network as a result of releases through the Kakhovka dam. The concept of ecosystem, ecological and extremal (target) releases and sanitary addition to ecosystem release for liquidation of anthropogenic pollution was formulated and the volumes of all these releases for the Dnieper River mouth zone were estimated. This methodology and calculation methods can be used for ecosystem state and water quality management in regulated rivers.