Landscape ecological risk assessment and driving factors in East Africa

Abstract

Global climatic variations and intensified human activities have altered land use structures and disrupted landscape patterns, increasing landscape ecological risk. Assessing this risk contributes to the formulation of ecological conservation and sustainable development strategies. Research on landscape ecological risk assessment and its drivers in Africa, particularly in rapidly developing East Africa, remains insufficient, which hinders regional ecological risk management and sustainable economic development. We investigated landscape patterns and spatiotemporal variations in regional ecological risk from 1992 to 2022 in East Africa using Geodetector and Random Forest models, measured the explanatory power and interaction effects of natural and human drivers, and quantified their contributions. We found that landscape patterns changed drastically in East Africa. Woodland and sparse vegetation increased by 12.30 × 10⁴ km² and 2.89 × 10⁴ km², respectively; shrubland and bare land decreased by 11.10 × 10⁴ km² and 5.91 × 10⁴ km², respectively. Ecological risk showed a north-high, south-low spatial pattern with positive autocorrelation (P < 0.001). High, sub-high, and medium risk areas decreased, suggesting a downward trend. The distribution of landscape ecological risk in East Africa was mainly influenced by vegetation conditions and annual precipitation; vegetation change dominated the landscape ecological risk pattern, and natural and human factors influenced landscape resilience. Overall, our findings may inform ecological conservation planning in East Africa. Ecological management should give greater attention to vegetation protection and restoration, while landscape planning should consider regional precipitation conditions to help reduce ecological risk and promote sustainable development.