Preliminary Assessment of Forest Structure.pdf - Sokoine University ...

Proceedings of the first Climate Change Impacts, Mitigation and Adaptation Programme Scientific Conference, 2012Figure 2. Species diversity across the three study sites (spatial differences). There was an almostsignificant difference between Kilwa & Handeni study areas (F = 3.281; p = 0.055).3.2 Assemblages of forestcommunities in the study areaA non-metric multidimensional scaling(NMDS) of the tree samples from thestudy sites is shown in Figure 3a. TheSIMPROF test performed under clusteranalysis indicated internal structuring ofthe forest communities among studylocalities (Pi = 2.52; p = 0.1%). One wayanalysis of similarity (ANOSIM) alsoshowed strongly distinct assemblages offorest communities across the study sites(Global R = 0.673, p = 0.1%; Figure 3b ).The assemblages were particularlydifferent between Kilosa and Kilwa(Global R = 0.802, p = 0.1%) and betweenKilwa and Handeni (Global R = 0.85, p =0.1%) but less so between Kilosa andHandeni (Global R = 0.312, p = 0.1%).Further, analysis of similarity percentages(SIMPER) of forest communities betweenlocalities indicated the surveyed forestcommunities in Kilwa were similar foronly 27.79 % while Kilosa forestcommunities were similar for 17.35% andHandeni, 26.41%. Further examination ofspecies contribution to the observedassemblages showed considerabledifferences between and among forestcommunities in the study area.Pseudolachnostylis glauca was thedominant tree species in Kilwa(contribution, 27.85%) and contributedmost (7.13%; average dissimilarity 6.98 ±1.39) to the observed average dissimilaritybetween Kilwa and Kilosa communityassemblages (97.92%). The dominantspecies in Handeni was Combretum molle(contribution, 25.89%) while Brachystegiaspiciformis dominated in Kilosa forestcommunities (contribution, 30.64%). Onthe contrary, the average dissimilaritybetween Kilwa and Handeni forestcommunity assemblages (91.62%) was dueto Brachystegia spiciformis which had anaverage contribution of 6.80% (Averagedissimilarity 6.23 ± 1.46) over otherspecies in the study area.111