Spatial Patterns and Drivers of Chinese Lizard Richness among Multiple Scales

Species richness is one of the focuses of the preponderance of ecological studies. Latitudinal and altitudinal gradients of species richness are two wellknown macroecological patterns. Most studies on the macroecology of species richness and its determinants are mainly focused on a single scale, although a few include multiple scales. Across multiple scales, we can better understand the diversity gradients and the potential causes. Here, we gathered the maps of distribution for 212 species of Chinese lizards from published studies, and to describe the overall Chinese lizard richness patterns. We studied the relationships between the latitudinal and altitudinal patterns of species richness among Chinese lizards at the assemblage level. We further tested the relationship between lizard richness and environmental factors among multiple studied scales (large scale: 1.5 degrees x 13 degrees, medium scale: 1 degrees x 1 degrees, and small scale: 0.5 degrees x 0.5 degrees). Regions with higher species richness occurs in in south China, and we found negative latitudinal richness gradients. We found a low-altitude plateau pattern between species richness and altitude, and lizard richness decreased with altitude above 2500 m. Lizard richness was positively correlated with temperature and net primary productivity, but negatively correlated with actual evapotranspiration, temperature, and precipitation seasonality at all three scales. However, lizard species richness was positively correlated with heterogeneity only at the 1 degrees scale. Based on the results across multiple scales, we confirmed that the species richness patterns of Chinese lizards were driven by multiple factors, which consistent with the predictions of the ambient energy, seasonality, and productivity hypotheses. However, the relationship between lizard richness and heterogeneity differed among studied scales owing to the different levels of altitude heterogeneity within grids at different scales.