Wetland Plant Dominance Density And Biomass In Mara River Basin Wetland Upstream Of Lake Victoria In Tanzania

Abstract The dominance density and biomass of wetland plants were investigated in Mara River wetland upstream of Kirumi Bridge. The study site was surveyed to identify the suitable sampling points in the wetland. In-situ identification of plants was done in order to determine the vegetation zonations. Transects were developed at the inlet and outlet zones of the wetland where sampling points were established and identified by global positioning system. A transect survey was conducted through the wetland prior to determination of plant types dominance and density. A vegetation zonation by dominant plant community was estimated using ground transects surveys. The determination of above ground and below ground biomass was done by separating plants into leavesumbel stackculm shoot rhizomes and roots depending on the plant type. The results show that the dominant plant species were Cyperus papyrus Typha domingensis Phragmites australis Thelpteris interrupta Echnocloa pyramidalis Cyperus articulatus Chara spp. Eichhornia crassipes water hyacinth and Azola spp. which accounted for more than 50 of all the species recorded are an indication of a typical wetland habitat. Cyperus papyrus Typha domingensis and Phragmites australis were the most dominant species in the wetland. Cyperus Papyrus had higher biomass content of 4.3 kgDWm-2 than the rest of the species followed by Phragmites 3.74 kgDWm-2 but Typha domingensis had the least biomass content of the three with only 2.71 kgDWm-2. The above ground biomass for Cyperus Papyrus accounted for 65 of the total biomass for the same plant. However Typha domingensis had only 57 of the total biomass above ground. The average plant density was 3.2 plantsm2 and the mean plants nitrogen content was found to be 67.88 gNm-2.