Hydrogeochemical characteristics of interstitial water and overlying water in the lacustrine environment

Urszula Aleksander-Kwaterczak,Robert Zdechlik

doi:10.1007/s12665-016-6146-8

Urszula Aleksander-Kwaterczak, Robert Zdechlik

Open Access

https://doi.org/10.1007/s12665-016-6146-8

Copy DOI

Journal: Environmental Geology	Publication Date: Oct 1, 2016
Citations: 9	License type: CC BY 4.0

Affiliation: AGH University of Krakow

Abstract

This research was conducted in the lacustrine environment of Lake Wigry, one of the largest and deepest lakes in Poland. The main objective was to determine the relationship between the chemical composition of interstitial water, overlying water and bottom sediment in the different sedimentation conditions. Therefore, seven research positions were selected, taking into account different zones of lake and lithological type of deposits. Overlying water samples taken from zones with carbonate type of sediment (lacustrine chalk or calcareous gyttja) were characterized by slightly alkaline pH, similar hydrogeochemical type (HCO3–Ca–Mg, HCO3–SO4–Ca–Mg), low values of mineralization and low metal concentrations. The situation is different with the water taken from the zone of organic: detritus gyttja or dy deposits. Overlying water collected from the Hanczanska Bay (estuary of Czarna Hancza River) had the highest mineralization 552 mg/L, HCO3–Ca type and low metal concentrations, while water collected from the dystrophic lake was SO4–Ca–Mg type, low mineralized and acidic type. Studies of interstitial solutions collected from different lithological type of sediments showed noticeable chemical composition differences, both between the carbonate and organic sediments in the same reservoir, as well as in the same kind of sediment but exposed to different external conditions. The highest mineralization (2032 mg/L) was generally found in the interstitial water obtained from the detritus gyttja localized in the shallow positions, which are more exposed to pollution. The highest trace metals and nutrients content in the sediment and interstitial water found in the Czarna Hancza River estuary were a result of the input from increasing industrial wastewater, domestic sewage discharge and runoff from agricultural soil. A greater resistance to adsorption of contaminants characterizes sediments composed of the lacustrine chalk; mineralization of their pore solutions was significantly lower. This fact is probably also affected by very low mineralization and chemical composition of overlying water and sediment.

Highlights

Interstitial water constitutes the link between the aquatic sediment and the overlying water, with the sediment–water interface associated with steep gradients in density, particle and solution composition, activities of chemical species, pH, redox potential and biological activity between two phases (Santschi 1990)
Overlying water collected from the Hanczanska Bay had the highest mineralization 552 mg/L, HCO3–Ca type and low metal concentrations, while water collected from the dystrophic lake was SO4–Ca–Mg type, low mineralized and acidic type
(2032 mg/L) was generally found in the interstitial water obtained from the detritus gyttja localized in the shallow positions, which are more exposed to pollution

Summary

Introduction

Interstitial water constitutes the link between the aquatic sediment and the overlying water, with the sediment–water interface associated with steep gradients in density, particle and solution composition, activities of chemical species, pH, redox potential and biological activity between two phases (Santschi 1990). Knowledge of the chemical composition and its temporal and spatial variation of the interstitial water may explain the origin of water and its palaeohydrogeological processes. This can prove effective in assessing conditions. Environ Earth Sci (2016) 75:1352 of circulation and exchange rate of groundwater as well (Szczepanska et al 1980) It is useful in determining sediments’ participation in overlying water contamination (Aggett and O’Brien 1985). This is important in the case of reservoir dredging when there is a potential risk of migration of contaminants into the water and/or their mobilization within the sediment (Brannon et al 1980). The second are the factors and processes leading to changes in the original composition of water, for example, cation exchange reactions between the interstitial water and exchangeable rocks complex, processes of diffusion, ion movement or participation of the pore water in the minerals formation (Myslinska 1974)

Objectives

Methods

Conclusion