Water quality assessment using a multi-descriptor approach: integrating chemistry, diatom assemblages, and non-taxonomical diatom metrics in the Kashkan River, Lorestan province, Iran

The Kashkan River, situated in western Iran, is a significant waterway, primarily utilized for drinking water supply and agricultural purposes. Consequently, rigorous monitoring of the river’s water quality is imperative. Diatom’s teratological forms, and ecological stress indicators, play a crucial role in water quality assessment programs. Understanding the correlation between environmental factors and these teratological forms is crucial for accurate water quality indices. The primary objective of this study was to investigate the diatom teratological communities in the Kashkan River and explore their correlation with heavy metals, aiming to elucidate water quality dynamics. In spring 2019, 48 epipelic and epilithic samples were collected along the Kashkan River, considering the impact of anthropogenic activities on the river. Three distinct teratological forms were identified comprising type 1) deformities in valve outlines, type 2) deformities in striations, and type 3) mixed deformities. Notably, valve deformities in Achnanthidium minutissimum and Diatoma moniliformis were the most prevalent. Furthermore, the concentrations of Cd, Fe, and Cr in the sediments emerged as significant environmental variables associated with elevated heavy metal levels in the Kashkan River. Principal component analysis (PCA) highlighted that sedimentary Fe, Cu, and Cr concentrations were key factors influencing the composition of diatom teratological forms. Consequently, implementing a water quality management program is vital to enhance the overall water quality in the Kashkan River.

Water quality assessment using a multi-descriptor approach: integrating chemistry, diatom assemblages, and non-taxonomical diatom metrics in the Kashkan River, Lorestan province, Iran Keywords:

Anthropogenic activities , freshwater diatoms , Heavy metals , Kashkan River , teratology , water monitoring