Water Quality of Selected Fishing Beaches of Lake Victoria Kenyan Gulf

Abstract

Lake Victoria the second largest fresh water body in the world located in East Africa is a shared resource between Kenya, Tanzania and Uganda and enjoys a wide range of streams and rivers from as far as Burundi and Rwanda. The lake has environmentally undergone physical, chemical and biological changes in the last four decades, particularly rise in its trophic condition and decline in oxygen level, which affects the water quality and fish population dynamics. This study therefore set out to determine the quality of water in selected fishing beaches of Lake Victoria, Kenya with a view to report the possible pollution levels. pH was highest at Nyamasari and Kotieno (9.3 ± 0.1) and lowest at Nyachebe and Kichinjio (7.08 ± 0.1) whereas temperature was highest at Nyamasari (29.5˚C ± 0.0˚C) and lowest at Kichinjio (23.4˚C ± 0.2˚C). DO was highest at Kotieno (10.3 ± 0.2 mgL) and lowest at Seka (2.4 ± 0.1 mgL). Turbidity was highest at Uyoga (125.5 ± 0.90 NTU) and lowest at Osieko (2.7 ± 0.1 NTU). Ammoniacal nitrogen was highest at Dunga (1278.3 ± 0.8 μg•l −1) and lowest at Nyamasari (12.4 ± 0.8), all a factor of human activities, lake substratum and effluents from rivers and surface runoff. All parameters assessed showed significant differences across sampling sites and depth except pH which did not vary significantly with distance from lakeshore. Further, all parameters did not show a clear pattern with respect to distance from the lakeshore possibly due to adequate mixing in the gulf. There is a need for further water quality monitoring by seasons to inform policy decisions towards sustainable lake exploitation.

Environmental and Management Factors That Influence <i>Commelina</i> Species in Selected Agro-Ecological Zones in Western Kenya

“…According to Orina et al [58] [59], the water body of Lake Victoria has experienced several changes regarding physico-chemical properties in the last past decades caused by human activities increasing toxic pollution from inappro-priate application of fertilizers, industrial and domestic waste discharge considered as secondary source of sodicity. Another possible reason for these nutrients to affect the diversity of Commelina species is perhaps that, our study area is predominant with hand hoe tillage in a perennial cropping system.…”

Water quality, phytoplankton composition and microcystin concentrations in Kisumu Bay (Kenya) of Lake Victoria after a prolonged water hyacinth infestation period

“…Past and more recent studies in the Lake Victoria basin indicate human activities are a major source of nitrogen and phosphorus (Lung'ayia et al, 2000(Lung'ayia et al, , 2001Orina et al, 2020) that encourage excessive phytoplankton growths in the lake (Sitoki et al, 2012).…”

“…The abundance and diversity of the phytoplankton are mainly regulated by inorganic nutrients that include, but are not limited to, nitrogen, phosphorus and silica. Nutrient enrichment from agricultural runoff and low-lying deforested riparian zones contribute to eutrophication of the lake (Lungayia et al, 2001;Orina et al, 2020;Triest et al, 2012). Similarly, the release of untreated or poorly treated domestic sewage directly into the lake contributes further to the lake's eutrophication (Ndaruga et al, 2004), thereby enhancing the proliferation of algal blooms.…”