Predicting suitable habitats of parasitic desert species based on Biomod2 ensemble model: Cynomorium songaricum rupr and its host plants as an example

As a species of considerable medicinal, ecological, and economic significance, the protection of C. songaricum and its host plants is of paramount importance. Biodiversity patterns and species distribution are profoundly influenced by climate change. Understanding the adaptive mechanisms of organisms in response to these changes is essential for effective species conservation. However, there is currently limited information available on simulating habitat suitability and assessing key environmental factors associated with parasite species using niche models. This study utilized environmental and species distribution data to analyze the shifts in the geographic range of C. songaricum and its host plants under current and projected future climate scenarios using the Biomod2 platform, which integrates multiple individual models into an ensemble framework. Additionally, the study quantified the environmental variables influencing the observed distribution patterns. The potential geographical distribution and overlapping areas of C. songaricum and its host plants are primarily concentrated in Asia and North America. Under all four scenarios within the two timeframes (2041–2060 and 2061–2080), the overall suitable habitat areas for C. songaricum, Nitraria tangutorum Bobr., N. sphaerocarpa Maxim., and Peganum multisectum (Maxim.) Bobrov are expected to decrease compared with current climatic conditions. Conversely, the total area of suitable habitat for Kalidium foliatum (Pall.) Moq., Nitraria sibirica Pall., and Zygophyllum xanthoxylum (Bunge) Maxim. is predicted to increase. All species except K. foliatum will experience greater reductions between 2041 and 2060 than between 2061 and 2080 under more severe climate change scenarios. There is significant ecological niche overlap among C. songaricum, N. sphaerocarpa, N. tangutorum, and P. multisectum. Key factors influencing the future distribution of C. songaricum include the mean ultraviolet-B light of the lowest month, altitude, and annual mean temperature. A comprehensive analysis demonstrated that the accuracy of predictions could be significantly enhanced and the distributional error for individual species could be minimized by employing the Biomod2 ensemble model to simulate the suitable habitats of parasitic species. The findings of this study can significantly inform both the management of C. songaricum plantations and the conservation of C. songaricum and its host plants.