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Published 11. Jun 2025 by WeForest in Project Desa’a
How to restore a biodiversity hotspot—one drop of water at a time

Travel to the western escarpment of the Great Rift Valley in northern Ethiopia, and you’ll find Desa’a Forest, a fragile patch of green clinging to life in an arid landscape. An estimated two billion tons of soil erode every year across Ethiopia, much of it in the north, where Desa’a lies. With 400 to 700 mm of annual rainfall, concentrated in a brief rainy season, desertification is advancing in the forest. Today, 70% of the forest has disappeared. Deforestation, overgrazing, and the accelerating impacts of climate change are threatening the remaining 30%, which is severely degraded. This, in turn, has led to dwindling harvests for over half a million people in Tigray and Afar who rely on its ecosystem services to survive.

As part of the Eastern Afromontane biodiversity hotspot, Desa’a is a refuge to rare and endangered species, including the Dragon tree. It’s also a natural water system. In 2021, a collaborative study conducted by WeForest and KU Leuven confirmed how ecologically unique Desa’a is. As an upper mountain cloud forest, it can intercept horizontal moisture, drawing water from clouds and mist air, even during the dry season. In fact, the study found that Desa’a’s canopy captures an average of 342 mm/m² of moisture annually. That’s 66% of its yearly rainfall — critical moisture to sustain crops during droughts.

Read the full article > https://www.weforest.org/blog/research/how-to-restore-a-biodiversity-hotspot-one-drop-of-water-at-a-time/