Prediction of ephemeral plant diversity patterns and identification of conservation priority areas in the Gurbantunggut Desert

Background Ephemeral plants are a key functional group in the Gurbantunggut Desert, contributing to windbreak, sand fixation, and biodiversity maintenance, while being highly sensitive to climate change. Understanding their spatial diversity patterns can reveal desert ecosystem adaptation mechanisms and inform conservation planning. This study examined 35 dominant ephemeral plant species in the Gurbantunggut Desert, Xinjiang. Using species occurrence data and 12 environmental variables, an ensemble species distribution model was applied to simulate spatial patterns of species richness and migration under current and future (2050s) climate scenarios (SSP1-2.6, SSP2-4.5, SSP3-7.0, SSP5-8.5). Climate velocity was calculated using the KNN algorithm. The Zonation model, integrating species richness, species loss, and climate velocity, was used to identify and optimize priority conservation areas. Results This study show that: (1) species richness declines under all scenarios toward the 2050s, with greater losses under higher emission pathways; the central southern margin consistently remains a biodiversity hotspot. (2) Climate velocity of temperature variables is higher in eastern and western regions, while precipitation variables show higher values in the east; overall, precipitation velocity exceeds temperature velocity. (3) Current conservation areas (2.103 × 10⁴ km²) are mainly in southern, western, and eastern regions. By the 2050s, conservation areas shrink (≈ 1.48–1.58 × 10⁴ km²) and shift, with higher-priority areas increasingly concentrated in the central southern margin and western desert under higher emission scenarios. Conclusion Future climate change will reduce ephemeral plant diversity and shift priority conservation areas, highlighting the need to protect the central southern margin and western desert.