Macro-invertebrate assemblages as indicator of ecological integrity of Kingwal Wetland

Abstract

In Kenya, the wetlands are undergoing continuous human encroachment and anthropogenic activities that may affect their ecological integrity. This study was conducted to assess this impact by establishing macroinvetebrates species and indices along different disturbance gradients. Data was collected monthly and analyzed through frequency distributions, cross-tabulation, chi-square, and Analysis of Variance as appropriate. Macroinvertebrates species richness was found to be highest at Kesses site which was a relatively low disturbance area with 28 species, followed by site Kingwal Bridge with 24 species and site Kiptenden with 23 species while Kimondi had the lowest species richness of 19 species. In terms of % OC relative to the total macroinvertebrate, Kesses had the highest value (6.1%) followed by Kingwal (4.5%), and the third was Kiptenden (1.9%). The overall % EPT was highest in the Kesses and lowest in Kingwal. Kesses had high IBI scores and these decreased downsream. There was generally a significant (p < 0.05) negative relationships between M-IBI and HDI. The current results indicate that the anthropogenic activities are resulting in differences in macroinvertebrate assemblages and can thus be used for biomonitoring.