An Assessment of Rainforest Distribution and Threats in the West Usambara Mountains, Tanzania

Abstract

Biodiversity hotspots across the globe have gained increasing attention in recent years. To accurately assess natural resource values and threats, timely information which characterizes the distribution and extent of natural land cover is needed. Many hotspots are in developing countries that have neither the resources nor the capability to carry out these tasks. This study seeks to address these issues in the West Usambara Mountains, within the Eastern Arc Mountain chain, of Tanzania. These mountains are one of the top biodiversity hotspots in the world. By incorporating remote sensing and Geographic Information System technology, this study develops spatial databases used to map current resource conditions and threats to existing biodiversity. Accuracy for landcover mapped with satellite imagery is 94%. Less than 10% of forest remains in large patches which are highly fragmented. The majority of this forest cover is found at high elevations, which correspond to relatively low potential biodiversity. Only 6% of forests are found at high biodiversity, lower elevation zones. More than half of the forest patch edges at these elevations are adjacent to conflicting landcover, such as small‐scale agriculture. This information can assist land managers and conservation professionals in the prioritization of protection efforts, conservation management, watershed stabilization, and forest restoration planning.