Influence of different land use types on bird and tree species diversity around lake Victoria basin in Bukoba municipality, Tanzania

Following a notable loss of biodiversity around Lake Victoria Basin in Tanzania, caused by fast population growth and unsustainable land uses, a study aiming at understanding the influence of different land use types on bird and tree species richness, abundance and diversity in Bukoba Municipality was initiated. The choice of the two biota was made based on the fact that avian and tree communities are good indicators of overall biodiversity and environmental decline or recovery. In identifying the types of land uses, two methods were used, which were direct observation and focus group discussion. The types of land use identified were home garden, fishing zone, open grassland, forest reserve and settlement. Bird and tree data collection in all land uses involved two methods, which were transects walk and direct observations. The data collected were about types and number of bird and tree species in each land use type. The data were analyzed by Microsoft excel, PRIMER 6 and Diversity programme 2007. The results showed that the Shannon-Weaver indices of bird diversity for homegarden, fishing zone, open grassland, forest reserve and settlement were 2.855, 2.793, 2.5, 1.791 and 2.054 respectively. The Shannon-Weaver indices of tree diversity for homegarden, fishing zone, open grassland, forest reserve and settlement were found to be 1.973, 0.7857, 1.726, 2.087 and 1.877 respectively. The results further showed that fishing zone land use had high bird diversity, while the highest diversity in tree species was noted in forest reserve land use. Therefore, the study concludes that there is greater variation in species richness between land uses, showing how each land use has an influence on species abundance, richness and diversity in the area. Again, increase in human population was seen as the problem in the maintenance of different land uses. It is recommended that deliberate, steps should be taken to maintain these land uses to their natural state, despite of the increase in human population, so as to maintain the habit of both bird and tree species.