Assessment of salt water intrusion patterns along the Wami river estuary and its implications on agricultural activities in Matipwili village, Bagamoyo district.

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University of Dar es Salaam
This study assessed the Salt Water Intrusion (SWI) phenomenon as one of the problems that can be caused by climate change elects as experienced in Matipwili village, Bagamoyo District. This study identified the vulnerability, extent and effects of SWI on agricultural activities and its impacts on peoples' livelihoods. Furthermore, the existing coping and adaptation measures against SWI were studied. The methodology employed included purpose sampling for selection of study area and key informants and focus group discussion for collection of data regarding farming history and understanding of climate change and variability. More over. Random sampling was used in the selection of households interviewed during the survey. Field observation and extensive literature review were also done. In addition, measuring potential hydrogen (pH) and Sodium Chloride (NaCI) content in soil and water was done during occurrence of SWI. The results showed that there has been an increase and decrease of rainfall amounts in the last twenty years, affecting agricultural production. This tallied well with from climatic data obtained from the Metrological Agency (TMA) in Bagamoyo which showed similar trends in the last thirty years. Furthermore, SWI occurred during the high tides rain season when the Wami River floods with saline water from the ocean to the farms, Kisauke-gobole sub village being the most affected one. The high salt content along estuary extended up to 5 km upstream, from the ocean to fame soils with the effect of crop burn, defoliation, yellow leaves, inability to produce and eventually death of the crop plant. The most affected crops in production are maize, banana and rice with the decrease from 16-20 bags/acre to 6-10 bags/acre within the last ten years. Food shortage and loss of income are the main negative impacts to the local farmers since production is deteriorating. The existing short term coping strategies are planting short temp crops such as vegetables, tomatoes and sweet potatoes after the cessation of heavy 'masika ' rains. Others included shining to other farms in the flood plains, food sharing during dry spells and fishing. All these measures were not sustainable therefore, the recommended long term adaptation measures should be; mangrove conservation through campaigning and by-laws, change of crop type to high salt tolerant ones, and initiate pump irrigation scheme during the dry season. Others include: shifting of the farms away from the flood plains to upland areas, seasonal water and soil quality regime profiling by the District's agriculture department to know the salt dynamics against crop growth. Also, improving the existing drainage system to minimise flooding and implementation of the integrated water resource management (IWRM) in the whole Wami River catchment (upstream and downstream) to ensure water availability and sustainability.
Available in print form, East Africana Collection, Dr. Wilbert Chagula Library, Class mark (THS EAF GB665.T34K57)
Salt water environment, Salt water instrusion, Agricultural activities, Wami river, Matipwili village, Bagamoyo district, Tanzania
Kitila, M. (2011). Assessment of salt water intrusion patterns along the Wami river estuary and its implications on agricultural activities in Matipwili village, Bagamoyo district. Master dissertation, University of Dar es Salaam. Dar es Salaam.