using the two-factor orthogonal design, UR and CA were the two
orthogonal factors. After down-weighting rare genus and/or family,
redundancy analysis (RDA) was performed to explore the relationships
between factors (i.e. UR and CA) and soil invertebrates (i.e.,
nematodes, mites and collembolans) by designating factors asnominal
(0, 1) environmental variables (Fiscus and Neher, 2002; Lepˇs
and ˇSmilauer, 2003). In this case, the data from UR treatment were
designated as 1 associated to UR factor but as 0 associated to CA
factor; the data from CA treatment were designated as 1 associated
to CA factor but as 0 associated to UR factor; the data from
CK treatment were designated as 0 associated to both UR and CA