This book seeks to elucidate the complex interplay between pollutants and biotic resilience within freshwater systems. It bridges ecological toxicology with biomonitoring frameworks to advance our understanding of pollution dynamics, species-specific tolerance thresholds, and the bioindicator potential of key taxa. It underscores the importance of integrated methodologies, spanning genomics, metabolomics, and traditional ecological assessments to predict and mitigate contaminant impacts. By embracing the One Health lens, it aligns scientific inquiry with conservation and public health imperatives. Features: Provides insights into biomonitoring techniques, including the use of bioindicators to assess pollution levels and ecosystem health Discusses species- and community-level pollution tolerance indices, offering quantitative tools for evaluating ecosystem resilience and stress thresholds Delineates ecotoxicological principles to explain the mechanisms of pollutant toxicity, bioaccumulation, and biomagnification in freshwater systems Reviews related sustainable water management aspects Offers an extensive overview of both conservation and aquatic ecological restoration This book is aimed at researchers and graduate students in environmental studies and ecology.