Spatial and temporal dynamics of water quality in aquatic ecosystems. A review of physical, chemical and biological gnomes of some Rivers in Malawi

Abstract

River ecosystems are among the most vulnerable aquatic systems in the face of increased, urbanization, land degradation, agricultural   activities, and careless disposal of sewage and waste water. This paper presents a review on substantial parameters in water quality   assessments for recreational purposes, domestic purposes and drinking. To attest good quality of water, multiple parameters have to be  measured. Physical, chemical and biological gnomes are tested to ascertain the water quality. Water quality studies on some Malawian  rivers evaluated various constituents such as phosphates, nitrates,pH, electrical conductivity (EC), total dissolved solids (TDs), heavy  metals and faecal coliforms. The mean values among the rivers were: PH (6.1-7.8), Phosphates (0.1-4.4mg/L), nitrates (0.05-9.79mg/L),  faecal coliforms (300-20408 cfu/100ml), Lead (0.05-0.74mg/L), Cadmium (0.004-0.14mg/L) and Manganese (0.4-1.8mg/L). The reviewed parameters exceeded World Health Organization (WHO) and Malawi Bureau of Standards (MBS) limits. This signifies that the studied  rivers to some extent are polluted and probably pose threat to the ecosystem health as well as public wellbeing. Therefore, there is a  need to intensify integrated management of water and land to curb further pollution of rivers.