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Although biomonitoring of freshwater bodies is important in East Africa as a result of increasing environmental threats, the identification guides of benthic macroinvertebrates used to generate data for developing metrics for this purpose are mainly not regionally specific. This casts doubt on the reliability and utility of generated data, given varying macroinvertebrate taxa in biogeographical regions. This review examined literature on freshwater macroinvertebrate studies and focused on the types of identification guides that are in use in East Africa, with a view of developing local ones for the region, to enable reliable and effective data collection and usage. The literature examined included peer-reviewed papers, books, dissertations, and un-refereed reports. Currently, it is mainly macroinvertebrate identification guides from temperate and other regions that are used in East Africa. Therefore, there is a need to develop identification guides that are based on local benthic macroinvertebrate species of East Africa. To achieve this, both lotic and lentic freshwater macroinvertebrates in various localities of East Africa should be collected through standardised protocols, taxonomically characterised and documented. Molecular phylogenetic tools, coupled with creation of a database should be considered to aid species identification of macroinvertebrates and freshwater biomonitoring in East Africa. [ABSTRACT FROM AUTHOR]

The study assessed household perception, attitude and expectations (PAE) on SWM in Kampala City and how PAE influenced household willingness to pay (WTP) for SWM services. The administrative Divisions of Kampala used in this study were purposively stratified according to parishes. Questionnaires were used as the main means of data collection on PAE. The determinants of WTP were established using the Logistic regression model while Tobit model was used to explain the factors that determine the maximum amount of money households were willing to pay. Contingent Valuation Method (CVM) was used to determine the value households attach to solid waste management services. Most households (59.9%) were not satisfied with solid waste management (SWM) services and perceived it as bad (35.7%) or very bad (22.9%). WTP for solid waste management services were by 48.1% of the households surveyed. Residents were on average WTP Ugandan Shillings 5,382 (USD 2.909) per month. The factors influencing WTP were gender (p<0.001), age (p=0.012), education level (p<0.001), income (p<0.001), marital status (p=0.036), household size (p<0.001) and migration status (p=0.045). [ABSTRACT FROM AUTHOR]

Loudetia phragmitoides (A. Peter) C.E. Hubbard is one of the dominant grass species occupying the Lake Nabugabo littoral wetlands, another prominent species being Miscanthedium violaceum (K. Schum) Robyns. Lake Nabugabo is a satellite lake, about 5 km to the west of Lake Victoria. It is a unique ecosystem, which is nutrient poor due to the highly leached ancient soils in the catchment. To determine the significance of wetland functions on the open lake ecosystem, the primary production and biomass decomposition process in the wetland of the dominant grass species, Loudetia phragmitoides were assessed. A biomass yield of 1638 gm−2 and an average primary production rate of 941 gm−2 year−1 were obtained for the Nabugabo wetland. Litter decomposed faster in the open lake compared with the littoral wetland with half of the litter weight lost in 110 and 321 days, respectively. Phosphorus leached more rapidly from decomposing litter compared with nitrogen. The study found that wetland dominant grass species can be an important nutrient reservoir and that the decomposition process in the wetland is influenced by the flooding regime, which exports significant nutrients (nitrogen and phosphorus) to the open lake. The importance of the littoral wetland to the overall ecology of the Nabugabo ecosystem is discussed. [ABSTRACT FROM AUTHOR]

In Kampala City like most towns in Uganda, provision of treated piped water has been concentrated in high-income zones with very little improvement in the high-density, low-income areas where the majority of the urban population lives. This has left protected springs as a major source of domestic water. These springs are “protected” during construction by providing provisions in two parts; a permeable section of gravel and sand into which the source waters enter, and a dam which prevents the water from bypassing the catchment or reservoir. A perforated supply pipe leads the water out of the reservoir. Very few studies have been carried out to determine the extent of pollution of protected springs and none on the comparison of protected springs in high- and low-density settlements. This study, carried out both in the dry and wet seasons, was aimed at establishing the water quality of protected springs in Kampala and contributory pollution factors. Both high- and low-density settlement areas were studied. Survey using questionnaires and field observations were done to identify sources of pollutants and to relate them to human activities and explain the possible causes and sources of pollution of the springs.Pollution (chemical and biological) levels were higher in protected springs located in high-density settlement areas and this was attributed to poor waste-management practices. Human activities like construction of pit latrines, some located less than 5m upstream of protected springs, animal husbandry and indiscriminate dumping of wastes contributed to the presence of high levels of chemical and biological pollutants in the protected springs. Average concentrations of nitrate-nitrogen (49.5mg/l) and ammonium-nitrogen (7.3mg/l) and faecal coliforms (1.8×104 no./100ml) were recorded. Pollution levels were higher in the rainy season and this was attributed to storm water runoff and its infiltration into the ground water. The results indicate that water from protected springs poses a health risk to the communities using it. [Copyright &y& Elsevier]

Nutrient-rich effluents from municipal wastewater treatment plants (WWTPs) have significantly contributed to eutrophication of surface waters in East Africa. We used vertical (VF, 0.2 m(2)) and horizontal (HF, 0.45 m(2)) subsurface flow (SSF) constructed wetland (CW) configurations to design single-stage mesocosms planted with Cyperus papyrus, and operating under batch hydraulic loading regime (at a mean organic loading rate of 20 g COD m(-2) d(-1) for HF and 77 g COD m(-2) d(-1) for VF beds). The aim of the investigation was to assess the performance of SSF CWs as hotspots of nutrient transformation and removal processes between the WWTP and the receiving natural urban wetland environment in Kampala, Uganda. C. papyrus coupled with batch loading enhanced aerobic conditions and high efficiency regarding the elimination of suspended solids, organic matter, and nutrients with significant performance (P < .05) in VF mesocosms. The mean N and P elimination rates (g m(-2) d(-1)) were 9.16 N and 5.41 P in planted VF, and 1.97 N and 1.02 P in planted HF mesocosms, respectively. The lowest mean nutrient elimination rate (g m(-2) d(-1)) was 1.10 N and 0.62 P found in unplanted HF controls. Nutrient accumulation in plants and sediment retention were found to be essential processes. It can be concluded that whereas the SSF CWs may not function as independent treatment systems, they could be easily adopted as flexible and technologically less intensive options at a local scale, to increase the resilience of receiving environments by buffering peak loads from WWTPs.

Four forest reserves within 50 km of Kampala in Uganda act as a critical buffer to the Lake Victoria watershed and habitat for local populations. Over a 9-month period we capture a pioneering water quality data set that illustrates ecosystem health through the implementation of a water quality index (WQI). The WQI was calculated using field and laboratory data that reflect measured physical and chemical parameters (pH, dissolved oxygen, biological oxygen on demand, nitrates, phosphates, fecal coliform, and temperature turbidity). Overall, the WQI for the four forest reserves reflect poor to medium water quality. Results compared with US Environmental Protection Agency and World Health Organization drinking water standards indicate varying levels of contamination at most sites and all designated drinking water sources, with signatures of elevated nitrates, phosphates, and/or fecal coliforms. As critical health problems are known to arise with elevated exposure to contaminants in drinking water, this data set can be used to communicate necessary improvements within the watershed.