Browsing by Author "Tungaraza, C."

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Assessing significance of community documented climate impacts and adaptation preferences and options in the lake victoria region, Tanzania
(Ethiopian Journal of Environmental Studies & Management, 2017-02-13) Elisante, E.; Tungaraza, C.
The study was conducted in Ukerewe Island in the Lake Victoria, Tanzania in order to ascertain the communities’ awareness on climate change impacts and adaptation/coping strategies. The methodology involved randomly selected 420 people mostly farmers and fishermen who were interviewed and involved in focus groups. It was observed that communities were aware of the changes in climatic parameters consequently impacting their livelihood. The most significant impacts were scarcity of water and poor crop production which received 100% support of the respondents. Other impacts included the change of water quality of the Lake Victoria (94.5%) and loss of biodiversity (35.7%). On the non-climatic factors, the major concern was on population growth (98.3%), loss of soil fertility (96%) and deforestation (84.8%). Of the suggested adaption options, provision of alternative food crops and fertility improvement to increase production were highly supported with highest total score of 48 on an arbitrary total assessment scale of maximum of 50. This was also observed on fish farming activities. The observations highlighted gender-based labour division imbalance where women and children were shown to shoulder the burden. It can be concluded that communities in the Lake Victoria region are affected by multiple impacts related to climate and also those not related to climate. Under various impacts communities set their own coping and adaptation strategies based on importance to livelihood. However, there is a need for proper guidance on how adaptation strategies are being executed.
Ecotoxicity of mercury contaminated sediment collected from Mabubi river (Geita district, Tanzania) to the early life stages Of African catfish (clarias gariepinus)
(Elsevier, 2009) Chibunda, R.T; Pereka, A. E; Phiri, E.C.J; Tungaraza, C.
The quality of Hg contaminated sediments in artisanal gold mining areas of Tanzania have to date only been assessed through bulk chemical analysis. However, measurement of contaminant levels alone has a limited ability to predict adverse effects on living resources. In this study we investigated the possible effects of Hg contaminated sediments from the river Mabubi which drains the artisanal gold mine on the hatching success, larval survival and growth of the African catfish (Clarias gariepinus). The tested species is a resident fish whose demersal behaviour keeps it in frequent contact with the sediment. Sediments collected downstream of the mine decreased survival and impaired growth of Clarias gariepinus but did not affect its hatching success. These effects were observed up to six kilometres downstream of the mining activity. The calculated 5 d- LC 50 value (larval survival) was 1.75 μg/g Hg dw (95% CL of 0.72 – 2.53), the 5d-NOEC for hatching was >2.3 μg/g Hg dw and that for larval survival and growth was 0.23 μg/g Hg dw. In conclusion, chemistry and ecotoxicity results from this study suggest that sediments collected downstream of the mine adversely affect catfish and probably other fauna and as such present a considerable local environmental risk.