Heavy Metal Transport in a River-Reservoir System: a Case Study from Central Poland

Abstract

The development of dams alters the structure and function of river ecosystems. Dam reservoirs have an impact on flow regime, sediment transport, and water quality. Damming a river decreases water velocity, which leads to an increase in suspended sediments deposition. Reservoirs often are described as water treatment plants because they trap water contaminants and suspended sediments. Suspended sediments are the principal factor for heavy metals transport [1][2]. Human activity increased input of heavy metals to water bodies where sediments are deposited [3][4][5][6][7][8]. Amin et al. [9] and Zheng et. al. [10] reported that more than 90% of the heavy metal load in the water bodies has been associated with suspended particulate matter and sediments. The spatial and seasonal variations of heavy metal loads are controlled by suspended sediment concentrations as well as water pH, which controls the absorbance of heavy metals [11].The spatial distribution of sediments in a reservoir is not uniform [12]. Toward the dam, sediments are usually more fine-grained and lithologically uniform [13]. The heavy metals concentrations generally increased with the decrease of particle size and increase of organic matter. The concentration of heavy metals in Pol. AbstractThe aim of this study was to analyze the heavy metals transport in a river-reservoir system. Sediment samples from 25 locations (9 from the Powa River and 16 from the Stare Miasto Reservoir) were analyzed for trace metals contents (Cr, Ni, Cu, Zn, Cd, and Pb). The relationships between heavy metal concentrations and bottom sediment physical properties were determined with the use of the multivariate statistical techniques cluster analysis (CA), principal component analysis (PCA), and canonical correspondence analysis (CCA). The results showed that concentrations of heavy metals in the sediments of the reservoir were higher than those in the bottom sediments of the river. Concentrations of heavy metals in bottom sediments in the river above the reservoir were characterized by lower spatial variability. Decisive influence on heavy metal concentrations of bottom sediments had silt, clay, and total organic matter content.

Influence of Cascading River–Lake Systems on the Dynamics of Nutrient Circulation in Catchment Areas

“…Varol [69] and El-Amier et al [70] found that metal sedimentation processes can take place at the estuaries to reservoirs, which depends on the location of the delta and of the rushes. Sedimentation processes take place individually for each reservoir in the river-lake system and depend on water retention time, morphological conditions and other factors [25]. River sediments usually contain larger fractions than lake sediments [23].…”

“…Larger sediment fractions are deposited near the estuary of the river flowing into the reservoir, while smaller fractions, being lighter, are picked up from the bottom, transported and deposited farther [25]. The size of fractions, siltation and the abundance of organic matter are the factors that Sojka et al [25] found that determine the metal content in deposits, hence-according to their research-higher concentrations are found in lake sediments, especially deeper ones, further downstream from the inflow than in river sediments, due to the presence of fine fractions in them. Metal deposition in sediments of flow-through lakes is mainly affected by suspended sediments transported by the river [42].…”

Analysis of Shear Stress and Stream Power Spatial Distributions for Detection of Operational Problems in the Stare Miasto Reservoir

“…Water pollutants are also inhibited there, which improves water quality in the main part of the reservoir. However, pollutants are frequently deposited in the sediments (e.g., heavy metals) [14][15][16][17].…”

“…In literature such objects have been rarely analyzed. Two other problems are discussed: (a) water and sediment quality [15][16][17]19,20]; (b) reservoir sedimentation [4,5,11,[21][22][23]. These two processes make the described reservoir construction so attractive.…”

Analysis of Degradation Processes in Reservoirs Based on Remote Sensing Data

“…One of the most promising solutions seems to be two-stage reservoirs with a separated preliminary part. According to Wicher-Dysarz (2019) and Sojka et al (2018), the structure of the two-stage reservoirs has impact on the reduction of sediments and biogenic compounds which inflow into the main part. Another technical solution, which has been applied more frequently in the last years, is the structure of lateral reservoirs.…”