Determinants of species turnover
Four climate factors, two soil factors, and latitude factors were used
to assess the effects of the environment and space. Partial RDA analysis
indicated that the effects of
environment and space were 54.09% and 13.84%, respectively, for
overall faunas (Figure 6). The effects of pure climate on soil fauna
composition were the strongest (31.27%), followed by pure soil factors
(15.78%) and pure spatial factors (8.31%) for overall fauna order
compositions (Figure 6a). Therefore, environmental factors and primarily
climate, explained most of the variation in overall soil fauna order
compositions.
For phytophage faunas, the effects of pure climate were 29.95%, pure
soil were 9.65%, and pure spatial factors were 6.59% (Figure 6b). The
effects of pure climatic factors were stronger than those of pure soil
and pure spatial on soil animal composition, whereas for predacity
faunas, the effects of pure climatic and soil factors were basically the
same (Figure 6c). Moreover, the effects of pure climate factors on soil
fauna order compositions for predacity faunas were the lowest, and the
effects of pure soil and the spatially structured climatic factors were
the highest (Figure 6).