A descriptive assessment of the wetlands of the Lake Victoria basin in Tanzania

摘要

Lake Victoria is the second largest freshwater body in the world by surface area. It is a very important water body for the livelihood of people, particularly those living in its basin. The lake is currently facing many problems such as serious environmental degradation, pollution and overfishing. Mismanagement of wetlands which is another problem threatening the hydrological and ecological balance of the lake is discussed. This report provides: an overview of the Lake Victoria ecosystem; describes major wetlands of the Lake Victoria basin in Tanzania and their uses; identifies water supply, agriculture, fishing, conversion into other uses (mainly residential); and cattle grazing as main uses of wetlands; and discusses threats and changes faced by wetlands. Direct anthropogenic activities such as irrational uses of wetlands for agriculture, pollution and conversion of wetlands into settlement areas are responsible for wetland degradation and loss. Problems of sedimentation as a result of agricultural activities, hydrological changes of wetlands due to road construction and subsidence of wetlands due to excessive extraction of water are indirect results of human actions. Drought is the common natural cause for the change or loss of wetlands in the lake basin. Absence of wetlands policy, conflicting sectoral policies on issues related to wetlands, deficient planning concepts, limited information and awareness on the importance of wetlands and absence of an institution to deal specifically with wetland management contribute to degradation and loss of wetlands. A number of recommendations for sustainable use of wetlands are put forward. Formulation of the National Wetlands Policy and launching of awareness campaigns on wise use of wetlands are recommended. The presentation also emphasises carrying out of research on the proper utilisation of wetlands, monitoring of wetland uses and provision of sustainable exploitation of wetland resources extension services.