Browsing by Author "Odong, Robinson"

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How water exchange and seasonality affect the eutrophication of Murchison bay, lake Victoria
(Elsevier: Limnologica, 2015-07) Luyiga, Suzan; Haande, Sigrid; Semyalo, Ronald P.; Kizito, Yusuf S.; Miyingo-Kezimbira, Anne; Brettum, Pål; Solheim, Anne Lyche; Odong, Robinson; Asio, Santa Maria; Jensen, Knut Helge; Larsson, Petter
Murchison Bay in the Northern part of Lake Victoria has for decades received a daily wastewater load of 0.2% of its volume from Kampala City, through the Nakivubo channel. In spite of this, the Water Treatment Works abstracts raw water from this bay and has been able to produce drinking water of sufficient quality for the capital. This study monitored various physical−chemical components within the bay during 2000−2003 to understand the processes responsible for the acceptable quality of raw water. Four sampling stations were located along a transect from the channel mouth towards the open lake. Results showed that the wastewater did not accumulate in the bay, instead was already strongly diluted 2.5 km from the channel mouth. This caused an abrupt reduction in conductivity and the concentrations of the nutrients total phosphorus (Tot-P), orthophosphate (PO4-P) and total nitrogen (Tot-N). Inshore−offshore exchange of water was mediated by flows from daily and sub-daily water level fluctuations and wind-driven currents. As a daily average, 2% of the Murchison Bay flowed in and out and the incoming wastewater was diluted 9.7 times. During the dry season from June to August (D2), when the weather was influenced by the south-east monsoon, the thermal stratification in the main lake disappeared and cooler and deoxygenated water from deeper depths entered the bay influencing its water quality. The daily flushing of water in and out of the bay due to water level variation was identified as the main factor diluting the bay water.
The microbiology of Uganda’s large freshwater lakes experiencing anthropogenic and climatic perturbations : why it matters—a review
(The Royal Society, 2025-05-15) Abiriga, Daniel; Odong, Robinson; Bakyayita, Grace Kizito; Semyalo, Ronald; Okello, William; Grossart, Hans-Peter
Intensification of pollution of African water resources due to human activities together with climate change has serious implications for Africa’s blue economy, biodiversity and human health. Despite these overwhelming threats, there is limited research as evidenced by the underrepresentation Africa-based data in global ecological and biochemical models. This review, therefore, aims to highlight key challenges and existing research gaps, particularly in Ugandan freshwater ecosystems. We focus on lake microbiology as this scientific field has been greatly underrepresented. Aquatic microorganisms are situated at the base of lake food webs and thus play crucial roles in the evolution and maintenance of water quality, attenuation of pollutants, and control of biogeochemical cycling through the microbial loop. Until now, the microbiology of Ugandan lakes has not been systematically studied. Thus, many open fundamental microbial ecology questions need to be urgently addressed to generate valuable information to advance future research, education, management and policy in Uganda and beyond. These include, but are not limited to: identification of microbial taxa and functional genes in relation to anthropogenic and climatic influence; seasonal and spatial variation in species diversity and functions; diversity and functions of planktonic, sediment, biofilm and mat communities; antimicrobial resistance burden; plastisphere communities; and geomicrobiology.