The survival rates of ceriops tagal and rhizophora mucronata transplanted in areas of different environmental conditions in Mbweni mangrove.

This study compared the survival rates of Ceriops tagal and Rhizophora mucronata seedlings transplanted in cleared areas and the surrounding forested areas in four sites in Mbweni Mangrove Forest 5 km north of Dar es Salaam. These sites had been cleared for different lengths of time and for different purposes such as for firewood, building poles and hotel construction. Eight rows of mangrove seedlings of each of the two species were transplanted alternately through the cleared area into the surrounding forested areas in each of the four sites making a total of 640 seedlings. The survival / health status of all seedlings were evaluated on a 4-point scale after three months and certain abiotic factors were measured in all sites. Seedlings of Rhizophora mucronata showed significantly better survival health status than Ceriops tagal in all four sites, both in the cleared areas and in the surrounding forested areas. Both species showed significantly better survival in the forested areas than the cleared areas. The poor survival in cleared areas was attributed primarily to the extreme temperatures, salinity levels and desiccation that occurred there. The only site where the transplanted seedlings showed significantly different survival than the other sites was a site that had been clear cut several years previously for the construction of a hotel that never materialized. This is the only study site where Rhizophora mucronata seedlings have been transplanted over the past two years by an environmental women's group at Mbweni. There had also been natural regeneration of Ceriops tagal. These findings indicate that the restoration work had helped to improve the environment at this site, making it suitable for seedling survival. Thus, this study provides evidence for the importance of active ecosystem restoration.