Relationship between geological domain and physicochemical parameters in lotic system

Relação entre domínios geológicos e parâmetros físico-químicos em sistemas lóticos

ABSTRACT

In natural conditions, the characteristics of surface water and river sediments are determined by geological formation. These can be changed due to human activities and interfere with maintenance of aquatic biota. Thus, identifying patterns of surface water and sediments in different geological areas can help to detect possible changes in orientation and contribute to decision-making within the maintenance and conservation of aquatic environments. The objective of this research was to identify changes in physical and chemical characteristics of surface water and geochemistry of sediments inserted catchments in three geological areas in Paraná: metasedimentary carbonate domain (MSCD), terrigenous-carbonate sedimentary domain (TCSD) and basic magmatic domain (MBD). The electrical conductivity, alkalinity, hardness, concentration of Ca and Mg in water were higher in MSCD. The concentration of SiO₂ is more representative of the MBD and CO₂ in the TCSD. In PCA, with the results of physico-chemical parameters of water, the first axis explained 99.43% of the variance between the sampling stations. In geochemical analysis of sediment and only Fe₂O₃ CaO showed statistically significant difference (ANOVA = p<0.05). The results suggest that the studied catchments are in good condition and reflect the natural conditions for each geological domain, demonstrating the need for adequacy of law inherent in assessing the quality of surface water. This work can be used as a reference for future studies and monitoring programs of the assessed catchments.

Kewords: Water resources; River sediment; Environmental geology; Geochemistry; Surface water