Physico-chemical and microbiological data of the Mooi River : a historical perspective

Abstract

Increased urbanisation and anthropogenic disturbances have caused water quality of many freshwater systems to deteriorate over the years in South Africa. This is due to domestic, industrial, and agricultural waste being disposed of into surface waters and the surrounding environment. To meet growing water requirements a monitoring program needs to be applied nationally. Government agencies set forth this initiative by creating water management areas to meet integrated water resource management needs. Applying data mining techniques, this study attempts to determine the water quality status by analysing historical and current data of one of these management areas, specifically the Mooi River and Wonderfonteinspruit. It focuses on mining microbiological, physico-chemical and geographic information systems (GIS) data to explore relationships between bacterial communities and physico-chemical changes and the correlation between industrial pollution, agriculture and urbanisation on water quality. The results demonstrated that the Mooi River has water usable for all purposes, while the Wonderfonteinspruit’s water is highly polluted with PO43-, SO42- and NO3-NO2. The Wonderfonteinspruit sites also show high EC values. The bacterial community composition of the Mooi River and Wonderfonteinspruit seemed mostly similar. Bacteriodetes, Proteobacteria, Actinobacteria and Cyanobateria are the four most dominant phyla identified spatially and temporally, but the Wonderfonteinspruit had a higher abundance of Cyanobateria. The major land-use activities that influenced physico-chemical parameters and bacterial communities were identified as mining and agriculture, with erosion also playing a role.