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Table 1 Testing interspecific vertical root segregation either
based on root-placement patterns (MPDplacements)
throughout the 0-30 cm soil zone or relative root abundance
(MPDabundance) in the 0-10 (P1), 10-20 (P2) and 20-30 cm
(P3) soil zones using three different parameters. The similarity in
relative root abundance of co-occurring species was evaluated with mean
pairwise distances (MPD), standard deviation (SD) and variance
(Variance) of species relative root abundance. Values indicate the
proportions of root neighbourhoods with root segregation (Sepa.),
significant segregation (Sig-S.), aggregation (Aggr.) and significant
aggregation (Sig-A.). The mean of the standardized effect size of the
corresponding parameter was compared with the null expectation of zero
to examine whether it was significantly differed from zero across the
entire study site.