This study presents a comparative profiling of discharged sludge from two sewage treatment plants (STPs) located in Lucknow, Uttar Pradesh Bharwara (BS) and Daulatganj (DS). The investigation integrates physico-chemical characterization, FTIR spectroscopy, and 16S rDNA sequencing to assess differences in sludge composition and microbial community structure. Physico-chemical analysis revealed variations in parameters such as pH, total solids, and organic matter content, reflecting differing influent sources and treatment efficiency. Alpha diversity metrics, including Shannon entropy, Simpson index, and Chao1 index, indicated higher species richness and microbial evenness in DS compared to BS. Venn diagram analysis further confirmed greater microbial diversity in DS, with a larger number of unique ASVs/OTUs. FTIR spectral analysis identified major functional groups such as hydroxyl, carboxyl, amide, and aliphatic chains, with DS sludge showing greater complexity in organic composition. The results demonstrate that sludge characteristics are influenced by both treatment process and influent type. DS-STP exhibited more diverse microbial communities and organic signatures, indicating potential for better biodegradation and resource recovery. This integrated approach enhances understanding of microbial ecology and sludge management in wastewater treatment systems and can guide future environmental monitoring and reuse strategies.
Fazli et al. (2026) studied this question.