Abstract
Urbanization has induced substantial changes in soil physicochemical characteristic, which plays an important role in regulating soil fauna biodiversity in forests and grasslands. However, less is known about the urbanization effect on soil fauna biodiversity and how soil physicochemical changes mediate this effect. Along an urbanization gradient in the city of Guangzhou, we established four sites with different urbanization intensities, including an urban site, two suburban sites, and a rural site, and then studied their soil physicochemical characteristic and soil fauna biodiversity. The soil physicochemical characteristic dramatically changed along the urbanization gradient. In contrast, the soil fauna biodiversity exhibited a very different pattern. Soil fauna abundance was highest in the suburban sites. Moreover, there were significant changes of Pielou’s evenness and community structure in the suburban sites. Soil fauna biodiversity property in the urban site was similar to that in the rural site, except that the rural site was characterized by Enchytraeidae while the urban site was not characterized by any taxa. Our linear and canonical correspondence analysis models suggested that soil physicochemical characteristic only contributed a little to the variance of soil fauna abundance (19%), taxa number (27%), and community structure (12%). In contrast, soil physicochemical characteristic explained about half of the variance in Shannon’s diversity and Pielou’s evenness. However, with urbanization intensity increasing, soil physicochemical changes could both increase and decrease the diversity and evenness. Thus, our results revealed an inconsistent pattern between soil fauna biodiversity and soil physicochemical characteristic along an urbanization gradient. This study suggested that soil physicochemical change was less important as expected in regulating soil fauna biodiversity pattern under an urbanization context. To elucidate the effect of urbanization on soil fauna biodiversity, further studies should take other urbanization agents into account.
Highlights
Urbanization is among the most dramatic changes in terrestrial ecosystem surface, resulting in a series of substantial abiotic and biotic changes (McIntyre et al, 2001; Veresoglou et al, 2015; Eisenhauer et al, 2019)
We explored the influence of soil physicochemical characteristic on soil fauna community structure using canonical correspondence analysis (CCA) with backward stepwise selection of a priori explanatory variables (i.e., bulk density (BD), soil water content (SWC), pH, SOC, total nitrogen content (TN), total phosphorus content (TP), Cd, Cr, Cu, Pb, and Zn)
Gradual changes were observed in BD (Figure 2A), SWC (Figure 2F), Cu (Figure 2H), and Pb (Figure 2J)
Summary
Urbanization is among the most dramatic changes in terrestrial ecosystem surface, resulting in a series of substantial abiotic and biotic changes (McIntyre et al, 2001; Veresoglou et al, 2015; Eisenhauer et al, 2019). Soil fauna biodiversity is generally regulated by population dispersal limitation, environmental influence, and biotic interaction (Vellend, 2010; Gao M. et al, 2020). Urbanization has induced substantial changes in soil physicochemical characteristic, but less is known about its effects on soil fauna biodiversity. In natural and seminatural ecosystems, soil physicochemical characteristic plays a vital role in regulating soil fauna biodiversity (Coleman et al, 2004). It is unclear that in human-dominant urban ecosystems, how soil physicochemical changes will mediate the effects of urbanization on soil fauna biodiversity
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
