Bacillariophyta (diatoms) are important primary producers in freshwater ecosystems and are widely used as bioindicators of water quality and ecological conditions. This study investigated the taxonomic diversity, seasonal distribution, and relationships between Bacillariophyta assemblages and physicochemical characteristics of the Dor River, Abbottabad, Khyber Pakhtunkhwa, Pakistan, during 2021–2022. Monthly sampling was conducted at eight selected sites, and algal taxa were identified using standard morphological and taxonomic approaches. Physicochemical parameters were analyzed following standard protocols, while phytosociological indices and Principal Component Analysis (PCA) were used to characterize community structure and explore patterns in relation to environmental variables. A total of 46 Bacillariophyta taxa were recorded, representing two classes, ten orders, and nineteen families. Bacillariaceae, Gomphonemataceae, and Naviculaceae were among the most species-rich families, while Naviculales was the most species-rich order. Bacillariophyceae was the dominant class in the recorded assemblage. Seasonal patterns in diatom diversity and abundance varied throughout the study period, with higher values reported in December, February, and March. Navicula laterostrata had the highest reported density and Importance Value Index (IVI), whereas Navicula cryptocephala exhibited the highest frequency of occurrence. Diversity indices described variation in community structure across the sampling period. PCA revealed patterns of variation in diatom assemblages in relation to physicochemical parameters, suggesting potential relationships between environmental conditions and community composition without establishing direct causal effects. This study provides a baseline assessment of Bacillariophyta diversity in the Dor River and contributes information on the seasonal distribution of diatom assemblages and their relationships with measured water-quality parameters. Continued monitoring of diatom communities and physicochemical characteristics may support future assessments of river ecology and inform water-quality management and biodiversity conservation.
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- Article
Diversity and Seasonal Distribution of Bacillariophyta in Relation to Physicochemical Characteristics of the Dor River, Abbottabad, Pakistan
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Received: 17 August 2026 | Revised: 21 October 2026 | Accepted: 26 October 2026 | Published: 05 November 2026
Abstract
Graphical Abstract
Keywords
bacillariophyta | freshwater diatoms | physicochemical parameters | seasonal distribution | water quality | bioindicators
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