Ecological drivers of Odonata beta diversity in arid and semi-arid regions of the Central Plateau of Iran

Freshwater habitats are among the most threatened and least studied habitats in arid regions of Iran. Discovering factors responsible for the spatial variation of biodiversity are one of the main considerations in conservation biology. As a first step towards developing conservation strategies, we aimed to investigate the beta diversity and response of Odonata assemblages to climate and landscape variables in arid and semi-arid regions of Iran. A total of 120 water bodies were surveyed. The beta diversity distance matrices were calculated for Odonata, Anisoptera, and Zygoptera, using the Jaccard dissimilarity coefficient. Also, the replacement and richness difference components of Odonata beta diversity were computed. Each of the five dissimilarity matrices was modelled by generalised dissimilarity modelling (GDM). We recorded 58 species of Odonata that represent 58% of the Odonata species in Iran. The average total beta diversity was high (0.873). GDMs results showed that the most influential variables varied between the replacement and richness difference components of Odonata beta diversity as well as between the two Odonata suborders. Anisoptera were most strongly affected by the temperature annual range, while the most important variable for Zygoptera was the average wind speed in April. Our results suggest that the studies of the drivers of biodiversity patterns benefit from beta diversity partitioning also from comparing species groups with different ecological preferences. The high biodiversity of the studied water bodies as well as the anthropogenic and climate threats that they are faced with, make these ecosystems a conservation priority.