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bioRxiv · 10.1101/2025.06.25.661646

The Future of Juniperus procera in Ethiopia under Climate Change Secnarios - Implications for Ecosystem Rehabilitation and Biodiversity Conservation

Woldu, Z.·Zeleke, G.
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Abstract

Juniperus procera, a keystone conifer of Ethiopias dry Afromontane forests, is increasingly threatened by climate change and land-use pressures. This study employed an ensemble species distribution modeling (SDM) approach integrating Random Forest, MaxEnt, and Boosted Regression Trees to predict the species current and future habitat suitability under two climate scenarios: SSP2-4.5 (intermediate emissions) and SSP5-8.5 (high emissions) for the 2061-2080 period. High-resolution bioclimatic variables and a curated dataset of georeferenced occurrence records were used to calibrate and validate the models. To ensure robustness, variable selection was performed through correlation filtering, and models were evaluated using AUC, TSS, and Kappa metrics. Model outputs revealed a marked contraction of highly suitable habitats under both scenarios, with losses reaching up to 85% under SSP5-8.5. In contrast, areas currently classified as unsuitable are projected to gain suitability, particularly in lower elevation belts of moist Afromontane zones, and higher elevation belts in northern Ethiopia suggesting potential downslope range shifts. Delta maps and transition matrices indicated widespread redistribution, including fragmentation and quality downgrading of core habitats. These findings highlight the dual challenges and opportunities posed by climate change for J. procera. While habitat loss and ecological fragmentation threaten long-term species viability, gains in new areas may offer pathways for adaptation provided dispersal, land use, and landscape connectivity are addressed. This study underscores the need for climate-informed, spatially explicit conservation strategies. Recommendations include prioritizing in-situ protection of climate refugia, promoting assisted migration to emerging suitable zones, and restoring degraded landscapes to support ecological resilience. These insights support ecosystem-based adaptation and sustainable forest management planning under Ethiopias national conservation and afforestation initiatives.

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Woldu, Z., Zeleke, G.. 2025-06-27. The Future of Juniperus procera in Ethiopia under Climate Change Secnarios - Implications for Ecosystem Rehabilitation and Biodiversity Conservation. https://doi.org/10.1101/2025.06.25.661646

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