Effects of abattoir wastes on benthic macroinvertebrates of the Elechi creek, Port Harcourt, Rivers state, Nigeria

Abstract

The effect of abattoir waste on the benthic macro-invertebrates of the Elechi creek Port Harcourt was undertaken between June 2012 and August 2012, to assess the impact of biological oxygen demand, dissolved oxygen, chemical oxygen demand, total suspended solid, total dissolved solid, temperature, faecal coliform counts and total coliform counts on the composition and distribution of benthic organisms. Ten taxa representing nine families were recorded. The most abundant groups was crustacean which accounted for 30.0% and 3 species of the ten taxa recorded. Oligochaeta, polychaeta and Hirudinea has 20.0% respectively and this accounted for 2 taxa each while insect had only one taxa with 10.0% composition. There was variation in the density of macro-invertebrates from station 1 to 3, the highest density was in station 1 (103) and followed in decreasing order in subsequent stations. Station 2 (30) and station 3 (25). Tubficid sp was highest in station 1 (40) which decreased progressively in subsequent stations, station 2 (10) and station 3 (8). This amounted to a mean density of 19.3 per m² while Desmocaris trispinosa  was 4 species with a mean density of 1.3 per m². The deterioration of water quality is evident by high BOD, (60mg/L), COD (54.0mg/L), DO (12.08mg/L), TDS (40.00mg/L), TSS (1360.00mg/L), and low temperature of (26⁰C). Values of microbial analysis ranged from 1600 to 2400 MPN/100ml for total coliform count while faecial coliform count ranged from 4 to 2400MPN/100ml. The results indicated that abattoir wastes have adverse effect on the benthic macroinvertebrates. This observation showed that with a continuous discharge of waste into the aquatic ecosystem could lead to the death of aquatic organisms in the water bodies.

Keywords: Pollution, wastes, benethic macroinvertebrates, abattoir and slaughter.