Abstract
Rural rivers play an important role as a major water supply in most parts of Northern Nigeria. Wanzum River is a major source of water to nearby communities. It serves various purposes, such as source of drinking water, fishing, irrigation and other domestic purpose. In this study, we explored the impact of human activities on macroinvertebrates assemblage and physicochemical data to ascertain the water quality status of the river. Samples of Physicochemical parameters and macroinvertebrates were collected from four (4) different stations for 12 months (December 2021-November 2022) using standard methods and procedures. The result of all the physicochemical data measured showed no significant (P>0.05) difference among the sampling stations except dissolved oxygen and turbidity. However, all the monitored physicochemical parameters differed significantly (P < 0.05) among the sampling months except dissolved
oxygen. A total of 1385 individuals from 36 macroinvertebrates species were collected from all the sampled stations. Hemiptera had highest number with 760 individuals, Coleoptera (228 individuals), Odonata (138 individuals) and Trichoptera (3 individuals). The constructed Principal Component Analysis (PCA) correlation matrix was able to separate the perturbed and the less perturbed stations from each other as station1 and 4 which were the less perturbed, correlated positively with PCA axis 1. The canonical correspondence analysis (CCA) result showed little or no positive correlation between macroinvertebrate assemblages and the measured environmental variables as eigen value of both CCA axis is less than 1 (<1). The low abundance of Pollution sensitive taxa such as the Ephemeroptera and Trichoptera, as well as the high abundance of Hemiptera, and Coleoptera indicate that Wanzum River is being stressed along its course. Obviously, sampling stations 2 and 3 showed this stress as they recorded no members of Trichoptera group.