Influence of Hydrologic Alteration on Sediment, Dissolved Load and Nutrient Downstream Transfer Continuity in a River: Example Lower Brda River Cascade Dams (Poland)

Abstract

Hydrologic alternation of river systems is an essential factor of human activity. Cascade-dammed waters are characterized by the disturbed outflow of material from the catchment. Changes in sediment, dissolved load and nutrient balance are among the base indicators of water resource monitoring. This research was based on the use of hydrological and water quality data (1984–2017) and the Indicators of Hydrologic Alteration (IHA) method to determine the influence of river regime changes on downstream transfer continuity of sediments and nutrients in the example of the Lower Brda river cascade dams (Poland). Two types of regimes were used: hydropeaking (1984–2000) and run–of–river (2001–2017). Using the IHA method and water quality data, a qualitative and quantitative relationship were demonstrated between changes of regime operation and sediment and nutrient balance. The use of sites above and below the cascade made it possible to determine sediment, dissolved load, and nutrient trapping and removing processes. Studies have shown that changes in operation regime influenced the supply chain and continuity of sediment and nutrient transport in cascade-dammed rivers. The conducted research showed that sustainable management of sediment and nutrient in the alternated catchment helps achieve good ecological status of the water.

Integration of Water Quantity/Quality Needs with Socio-Economical Issues: A Focus on Monitoring and Modelling

“…Szatten et al [16] discussed the impact of human induced hydrologic alteration of river systems. The research focused on the Lower Brda river cascade dams (Poland) and used hydrological and water quality data from 1984 to 2017 and the Indicators of Hydrologic Alteration method to show how changes in regime operation affect sediment and nutrient balance.…”

Major Ion Chemistry of the Bheri (Snow-Fed) and the Babai (Rain-Fed) River Systems in Western Nepal: Implication on Water Quality

“…Furthermore, water levels and renewal rates decline in downstream main channels (Pittock et al, 2009), disrupt river connectivity, and flood plains and channel connectivity (Bunn and Arthington, 2002;Grant et al, 2012). Changes in water transparency, nutrient and sediment loads, channel morphology and granulometry are some of the long-term physico-chemical effects of dams on downstream (Granzotti et al, 2018;Kamidis et al, 2021;Szatten et al, 2021;Yang et al, 2021), potentially leading to long-term oligotrophic-cation (Stockner et al, 2000;He et al, 2020). For instance, water transfer of São Francisco River in Brazil has been shown to cause algal blooms in receiving reservoirs (de Lucena Barbosa et al, 2021), decrease in dissolved oxygen content, and increased turbidity and salinity in Atibaia to Jundiaí transfer (Machado et al, 2018).…”