Impact of urbanization on the ecology of little Ruaha wetland A Case Study of Iringa Municipal

The ability of wetland ecosystems to function well is dependent on proper utilization, management as well as functional ecological integrity. Despite these wetland areas worldwide are being converted to other land uses due to growing human population and increased human activities. The study aimed at examining the impact of urbanization on the ecology of Little Ruaha wetland in Iringa Municipal. Specific objectives were to (i) assess the spatial and temporal changes in land use/cover from 1990 to 2000 and to year 2014 in the study area, (ii) assess the impact of land use/cover changes on wild animals and plant species composition, (iii) compare the abundance of exotic to native species and (iv) assess the impacts of human activities on water quality of the area. This study was conducted in two wards namely Kitwiru and Ruaha. A cross section research design was applied and research tools used were household interviews, focus group discussion, key informant interviews, field observation and literature review. Landsat TM images of 1990, 2000 and 2014 were used to assess the land use/cover changes to complement the socio-economic data. Respondents were selected through purposive and simple random sampling. A total of 105 household heads were involved in the study. Four sampling sites were established to assess the water quality of the area. Data were analysed through Statistical Package for Social Sciences (SPSS), theme-content techniques, Geographical Information System and water samples results were compared with the WHO guidelines and Tanzania Water Quality Standards. Findings of the study has revealed that there has been an increased settlement development from 3% to 5% and cultivated land from 17% to 35% in year 1990 - 2014, that was associated with increased human population data. Woodland, bush land and grassland showed a decreasing trend between 1990 and 2014. Various discussions also indicated decrease in wild animals probably due to on-going habitat destruction which was largely associated with the increasing forest clearance. Further analysis showed that native plant species were significantly higher than exotic tree plantation (t=3.095, df=8, P=0.02) indicating that, despite the on-going land use changes, the local communities have kept most of the native vegetation. Despite the increasing human activities in the area, the water quality results indicated that most of the sampled parameters were within acceptable range of both national standards and World Health Organization (WHO) guidelines. The study concluded that Little Ruaha wetland is experiencing some significant degradation that threatens its ecological integrity, thus there is a need for proper land use plan for enhanced sustainability of wetland resources.