Assessment of water quality using biological monitoring working party (BMWP) and average score per taxon (ASPT) score at Kanye and Magaga dams, Kano

Abstract

Macro invertebrate biotic indices have been widely used to assess quality of water bodies in the world. The Biological Monitoring Working Party (BMWP) and its Average Score Per Taxon (ASPT) score system is one of the most common biotic indices in use and has been applied to various streams and rivers throughout Europe and world. This study examines the water quality at Kanye and Magaga Dams using the BMWP/ASPT score index for the first time. Macro invertebrates were sampled from the upper and lower parts of the Dam using standard kick sampling techniques and identified to family level. The computed BMWP/ASPT score revealed higher value at the upper parts than the lower parts of the Dams. Kanye Dam showed a cumulative BMWP/ASPT scores of 50 and 3.85 while at Madaga Dam the cumulative BMWP/ASPT scores were 61 and 2.66 respectively, which are within class III category of moderately polluted water body. One way analysis of variance result revealed a significant difference (p<0.05) in BMWP/ASPT score value between the lower and upper part of both Dams. The result showed macro invertebrates were more diverse at the upper part than the lower part of the Dams. This study has further strengthened the use of BMWP/ASPT score index as an index of organic pollution in Nigerian water bodies. However additional application and validation is required to develop an adopted version BMWP/ASPT score index based on the sensitivity of our local taxa. Key words: Biotic index, Macro invertebrates, Pollution,