River water quality assessment based on a multi-descriptor approach including chemistry, diatom assemblage structure, and non-taxonomical diatom metrics

Abstract

In the present study, the ecological status of four major South Korean rivers flowing near industrial complexes is assessed using physico-chemical analyses and various descriptors based on periphytic diatom assemblages. Principal component analysis conducted with physical and chemical variables singled-out four sites as more severely impacted (higher concentration of metals and total nitrogen, higher conductivity and biological oxygen demand), while the remaining 12 sites indicated less impacted conditions, although showing nutrient enrichment. Less-contaminated sites based on physico-chemical properties showed higher cell densities, higher richness and diversity, a larger proportion of live and healthy-looking diatoms, lower production of lipid bodies (in terms of number and size) and fewer teratologies than more-contaminated sites. Non-taxonomical metrics (cell heath status, cell size, lipid bodies and valve deformities) were in good agreement with traditional taxonomical metrics (assemblage structure, richness, diversity). Overall, water quality assessment based on diatom assemblages and diatom-based metrics had a good fit with the available physico-chemical data and agreed on the most impacted sites. However, additional sites showed signs of degradation based on the diatom metrics used. This suggests that the use of biotic indicators provides useful complementary information on the health status at the selected sites.

Diatoms recovery from wastewater: Overview from an ecological and economic perspective

“…support the lives of a large variety of organisms but excessive urbanization and industrialization transform them into the heavily polluted zone [ 9 , 10 ]. The rising pollution level deteriorates the water quality index leading to a huge decline in species diversity due to untreated discharge of metals, pesticides, aromatic polycyclic hydrocarbons, etc., which slows down the survival of an aquatic species, thus posing a big threat [ 11 ]. Several organisms have been used as bioindicators such as protozoa, bacteria, fishes, zooplankton, algae, etc.…”

Physico-chemical variability and heavy metal pollution of surface sediment in a non-channeled section of Dilúvio Stream (Southern Brazil) and the influence of channeled section in sediment pollution

“…Channelization results in gradual degradation impacting the biotic and abiotic components of the system, which may lead to a high and fluctuating concentration of contaminants and nutrients (Pandey et al, 2018). A previous study in Lake Guaíba (De Andrade et al, 2018) shows that the main source of punctual sediment pollution in the margins of the Lake Guaíba comes from urban streams, such as Dilúvio.…”

Comparative Performance of Physicochemical-Based and Diatom-Based Metrics in Assessing the Water Quality of Mert Stream, Turkey

“…Anthropogenic eutrophication becomes a serious problem, which threatens the freshwater ecosystem worldwide due to the enrichment of water nutrients resulting from the industrial and intensive agricultural activities and leads to the deterioration of the water quality of rivers and lakes [Vörösmarty et al 2010]. The bioindicatorbased indices provide a valuable complement to the traditional physicochemical measurementbased indices to evaluate the ecological health of aquatic systems [Pandey et al 2018].…”