Ecological and water quality assessment of natural wetlands in kaffa zone, south west Ethiopia

Abstract

The distribution of macroinvertebrates metrics were undertaken to assess the ecological status and human impact in Kaffa natural Wetlands, south west Ethiopia. The study was carried out two rounds (Mid-January, 2014 and beginning of January, 2015). Macroinvertebrates, Physicochemical parameters of the water, human impact classes and habitat condition were assessed at five sites in the wetland exposed to different anthropogenic activities. The basic Prati index was also calculated based on the concentration of ammonium, chemical oxygen demand and oxygen saturation. Redundancy analysis (RDA) was applied to investigate relation between macroinvertebrates metric and environmental variables. The RDA analysis demonstrated that sensitive metrics such as EOT family richness and BMWP were positively associated with good habitat condition. In contrast, FBI was associated with disturbed habitat condition and high water electric conductivity. Furthermore, the Kruskal-Wallis test also indicated EOT family richness and BMWP were significantly higher in low disturbed habitats as compared to moderately to very highly disturbed sites (p<0.05).This study demonstrated that human disturbances such as uncontrolled grazing and farming contributed to the poor water quality and low abundance and richness of sensitivemacroinvertebrate taxa. Hence, good land management practices are essential to enhance biodiversity and ecosystem services of wetland ecosystems.