Assessing Fish Diversity, Water Quality, and Conservation Evidence in Mahakam Fish in the Tropical Rainforest Environment (Book Review)

Abstract

Fish biodiversity is a key indicator of aquatic ecosystem health and sustainable freshwater management, particularly in the diverse but increasingly pressured Mahakam River system. Mahakam Fish in the Tropical Rainforest Environment provides field-based information on fish biodiversity and aquatic environmental conditions. This review critically evaluates evidence on fish biodiversity, water quality, and fish conservation. A descriptive-analytical critical review was conducted based on sampling design, study coverage, data collection, and consistency of findings and recommendations. The study covered the Kedang Kepala River, Kedang Rantau River, and Lake Siran using seven sampling stations. Fish diversity was assessed using Shannon–Wiener, Evenness, Dominance, and Margalef indices, while water quality was evaluated using physicochemical parameters and the Storet method. Storet results classified the Kedang Kepala River as slightly polluted, Kedang Rantau River as moderately to heavily polluted, and Lake Siran as moderately polluted. Four introduced fish species were recorded, while Chitala borneensis was not captured and Notopterus notopterus was found. The book’s broad coverage of biological and physicochemical aspects is a major strength; however, the sampling design, temporal coverage, data integration, and ecological interpretation require further consideration. Future studies should incorporate long-term monitoring to strengthen evidence-based conservation and ecosystem management.