The Improvement of Water Quality Index and Distribution of Freshwater Fishes in Manjung River

Abstract

This project mainly studies the water quality of Manjung River in Perak, Malaysia. Five sampling sites were used to collect water quality and fish samples. The aim of this study is to verify water quality parameters based on the diversity of freshwater fish distribution. The second is to evaluate the influence of water quality on the distribution of freshwater fish. Finally, data on the diversity and distribution of fish in the study area will be analyzed. The method used in the data collection and analysis of this study is the collection of water samples in the designated study area using designated equipment. Nets and rods are used as a method to collect fish samples. Analysis of fish diversity (H'), richness (R'), and evenness (E') was performed using PAST software. Fish from 11 different species and 7 different families totaling 162 individual fish in total. Fish belonging to the Latidae family make up the majority of fish species in the region (15 species), followed by those belonging to the Cyprinidae family (18 species). Additionally, samples of three fish species were collected, including Oreochromis mossambicus, Pacific ladyfish, Lutjanus fulviflamma, Megalops cyprinoides and Prophagorus nieuhofi. In this river, pH is the most significant water quality factor for fish occurrence, followed by temperature, conductivity, dissolved oxygen, salinity, and turbidity. Data analysis showed that fish presence was influenced by several water quality factors, but not by the month of sampling. These findings provide fresh information from research on fish assemblages and habitat quality that may be important for future river fisheries and fish conservation.