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

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. Collections of samples, water, sediment and arthropods were carried out in the seven (7) sampling sites, observing standard procedures. The collected water and sediment samples were fixed with 1:1 nitric acid for the measurement of inorganic loads and heavy metals in the laboratory. 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 assess the water and sediment quality. 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. The diversity indices and Pearson correlation results revealed 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 aquatic arthropod species.