| dc.description.abstract | Nsooba stream is threatened by anthropogenic activities such as washing bays, industrialisation and farming which raise the nutrient loading concern to Lubigi wetland, a major filter of wastewater and flood control for various parts of Kampala city. Nine transects were sampled from three sites (3 on site A (before the activity), 3 on site B (on the activity) and 3 on site C (after the activity) along the stream for water quality, hydro-morphological and benthic macro-invertebrate, thrice in a period of two months i.e. (August and September 2022). Results indicated that pH significantly decreased along the stream as well as dissolved oxygen reduced along the stream. Meanwhile, water temperature remained within the natural ranges along the stream. The stream depth and flow rate gently increased along the stream, except for transects on where the activity was taking place which had a smaller stream depth and flow rate respectively. This was due to changes in water quality as a result of pollution from various anthropogenic activities such as dumping wastes and washing bay discharges directly into the stream thus accumulating organic matter in the water channel that is broken down resulting in variations in temperature and dissolved oxygen. The distribution of benthic macro-invertebrates varied with the water quality and near catchment activities along Nsooba stream. Along the stream before activity, sites recorded 9 families, on activity 11 families and after the activity having the least families of macroinvertebrates with 7 families. Individuals of macro-invertebrates belonging to 18 families were also identified and these included.
Chironomidae, Syrphidae, Simulidae, Tanyderidae, Elmidae, Gyrinidae, Coenagrionidae Corduliidae, Hydropsychidae, Nepidae, Physidae, Hydrobiidae, Planorbidae, Thiaridae, Achromadoridae, Hirudinea, Naididae, Hirudinidae. Naididae and Chironomidae were most abundant families at almost all the sites. There was no significant relationship between the physico-chemical and biological parameters except pH which did not affect the abundance and distribution of macroinvertebrates. In order to minimize pollution of streams, a distance of 30m away should be encouraged such that wastes from the nearby settlements are not directly disposed into the watercourse.
The study also recommends establishment of constructed wetlands to reduce waste accumulation and filter the run-off into the stream. | en_US |
