Abstract: Based on the distribution information of beetles and the data of climate and habitat in Ningxia, we explored the relationship between the distribution patterns of beetle species diversity and environmental factors. The results showed that species richness and fauna differentiation intensity of beetles were higher in southern and northern areas than in central area, and higher in western area than in eastern area. Results of clustering analysis showed that the geographic distribution of beetles in Ningxia could be classified into four groups (Liupan Mountain beetle group, loess plateau beetle group, desert oasis beetle group, and HelanLuoshan Mountain beetle group). Results of GAM analysis showed that mean temperature in the coldest season, mean precipitation of wettest month, and plant species richness were the dominant factors affecting beetle distribution. Variance decomposition results showed that water, energy and habitat heterogeneity together explained 82.4% of the total variations of beetle species richness. Energy and water factors together explained 79.6% of the spatial variation in beetle species richness, with independent explanations of 19.9% and 14.0%, respectively. Habitat heterogeneity explained 26.3% of the spatial variation, with only 2.8% independently. Our results indicate that beetle species richness patterns are predominantly shaped by energy and water factors together, and that habitat heterogeneity helps enhance beetle species richness in Ningxia.

Key words: beetle species diversity, distribution pattern, energy, water, habitat heterogeneity, Ningxia.