[01] Clemence Idukunda, Faculty of Environmental Studies, University of Lay Adventists of Kigali, Kigali City, Rwanda; Faculty of Arts and Social Sciences, the Open University of Tanzania, Dar es Salaam City, Tanzania. [02] Cosmas Benedict Mabarika Haule, Faculty of Arts and Social Sciences, the Open University of Tanzania, Dar es Salaam City, Tanzania. [03] Lamek Nahayo, Faculty of Environmental Studies, University of Lay Adventists of Kigali, Kigali City, Rwanda.

The current study assessed the vulnerability of mangrove forests to human activities in the coastal areas of Ununio, Mbweni and Pemba Mnazi in the United Republic of Tanzania. Land use changes in mangrove area were identified during transact walks on the fields before they were validated in Google Earth (GE) images. Major human activities affecting the study area were described associated with their influence on mangrove forests. GE images of 2003, 2010 and 2018 were analyzed in ArcGIS for mangrove area change detection and the extent of change was determined. The major human activities at Ununio and Mbweni were salt works, settlements, and trampling whereas at Pemba Mnazi, they were mangroves clearing for charcoal, timber, poles and building materials production. The analysis of the 2003 images indicated that Ununio, Mbweni and Pemba Mnazi had 104 ha, 75ha and 178 ha of mangroves, respectively. However, due to human encroachment, about 72%, 65.3% and 63.4% ha of the mangroves at Ununio, Mbweni and Pemba Mnazi, respectively, were cleared and converted to other land uses. The study concludes that mangroves are highly vulnerable to human activities in the study area, and recommends that effective conservation and management of mangrove habitats should be considered in association with local community participation.

Vulnerability, Coastal Vegetation, Mangrove Forests, Tanzania

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