Water and Sediment Quality Assessment, and Effect on Arthropod Species Diversity of Jaja Creek and Adjoining Downstream Section of the Imo River, South-South, Nigeria.

Abstract:

This study assessed the water and sediment quality and effect on the diversity of arthropod species of Jaja Creek and adjoining downstream section of Imo River. Three (3) sampling sites each were marked out along the stretch of the Jaja creek and adjoining Imo River, plus Control sampling site at the conference point of the Creek and the River. Collection of samples; water, sediment and arthropods, were carried out in the seven (7) sampling sites every month, observing standard procedures. The collected water and sediment samples were fixed with 1:1 Nitric acid for the measurement of physico-chemical parameters, inorganic loads, and heavy metals in the laboratory using standard methods. Collections of arthropod fauna were done across the seven sampling sites and they were stored in 70% ethyl alcohol until identification and counting. Single factor pollution index (SFpi) and Nemerow’s pollution index (PN) were calculated to assessed the water and sediment quality. The single-factor pollution index (SFpi) and Nemerow's pollution index (P N) of inorganic loads and heavy metals were calculated to find out the degree of pollution in the Jaja creek and adjoining Imo river. The Nemerow’s pollution index of sulphate, nitrate, phosphate, Iron, Manganese, Zinc, and Copper revealed that the water and sediment was polluted. Fifty (50) different arthropod species were identified and grouped into three classes of Crustaceans, Insecta, and Arachnida, with nine orders, and 23 families. Among the arthropod species identified in this study were Sesarmasp, Sesarma, Armases sp, Neosarmatium, Nematopalaemon sp, Macrobrachium, Penaeus sp, Callinectes amnicola, C. pellidus, Carcinus sp, and Chironomus sp. The diversity indices and pearson correlation results raveled that the water and sediment quality affected the arthropod species diversity. A strong conservation plan should be established for the preservation of the water bodies' and the well-being of the aquatic arthropod species.