MACROINVERTEBRATES AS INDICATOR OF POLLUTION; A CASE STUDY OF AAHOO STREAM

Abstract

Water covers about 70% of Earth’s surface. Safe drinking water is a basic need for all humans. World Health Organization reports that 80% of the diseases in the world are waterborne. Industrialization, discharge of domestic waste, radioactive waste, toxic chemicals, population growth, excessive use of pesticides, fertilizers and leakage from water tanks are the major sources of water pollution. The accelerated use of agricultural chemicals, indiscriminate disposal of industrial effluents and the population growth over the past few decades has had an adverse impact on the quality of surface waters in many areas of the world. All these have resulted in an increase in contaminants polluting waterways. Aquatic macroinvertebrates has therefore served as bioindicators. These biological indicators are species used to monitor the health of an environment or ecosystem. They are any biological species or group of species whose function, population, or status can be used to determine ecosystem or environmental integrity. The aim of this research work is to identify the extent at which macroinvertebrates can be used to detect the level of pollution of water from a stream associated with considerable human activities. The objectives of this study is to measure the physico-chemical parameters in the stream and also to determine the level of heavy metals and the abundance of macroinvertebrates in Aahoo stream. The result from this research shows that there are contaminants present in the Aahoo stream through the discharge of domestic and agricultural waste. The resulting effect can be disastrous to the aquatic organisms and cancerous to humans around Aahoo stream Water pollution, therefore, is of great consequence because both terrestrial and aquatic life may be affected; it may cause disease due to the presence of some hazardous substances, may distort the water community, add odours and significantly hinder economic activities.