Biodiversity of Mollusks in Rumaitha river-Iraq

Abstract

The chemical and physical parameters, density, spreading, biodiversity of Mollusca, and environmental features of Rumaitha district, South Iraq were investigated from July 2016 to June 2017. Mollusca and water samples were obtained from three dissimilar positions S1, S2, S3. The results were showed that water temperatures 12- 32ᵒC. The pH was ranged 7.21-8, 12 it showed a slightly alkaline trend. The maximum value of electrical conductivity 2.6 mS, Salinity values were ranged between 0.58-1.7 ‰ that indicated the water was Oligosaline during the study period, according to the classification of Reid. Dissolved oxygen was ranged 5.3-11 mg/l. The highest value of Ca++ and the organic content of the bottom sediments were 214 mg/l, 21.6% respectively recorded in station S2 during the study period. Quarterly variations in bulks of Mollusca species were obtained during study period recorded Total density of 817.89 indv /m2. In the present study, Mollusca fauna was identified 4 species belonging to 4 families of class Gastropoda and 3 species belonging to 2 families of class Pelecypoda. Gastropods Species are Melanoides tuberculata - Thiaridae, Melanopsis nodosa - Melanopsidae, Neritina crepidulare - Neritedae, and Viviparus bengalensis – Viviparidae. And their total density in the study period is (142, 24, 168.69, 44.45, and 106.68 indv/m² respectively. While the species belonging to the Class of Pelecypoda: Corbicula flumina, Corbicula fluminalis - Corbiculidae and Unio tigridis - Unionidae. And their total density in the study period are (151.13.80.01.106.68 indv/m² respectively. Biodiversity was low and did not exceed the diversity values of both classes. The highest value of varietal diversity of Gastropoda and was 0.43657 recorded at the station S1 during a month Apreil 2017. Sorensen Similarity was used to determine the similarity between stations taxa composition results showed that all study stations were 100% identical for Molluscs taxa.