The OVS was well correlated with RY for almost all crop
rotations at each study site (Table 6). This was more pronounced
for R2 and R3 at both study sites, and for R4 only at Flakkebjerg. The
OVS was also well correlated with RY for the reduced tillage
systems (H and D). However, the correlation of OVS with RY in H
was more pronounced at Flakkebjerg than at Foulum (R = 0.74 and
R = 0.38, respectively). The OSS index showed an almost similar
correlation with RY as for OVS (Table 6). However, OSS did not
correlate well with RY at Foulum for rotation R3 and R4 and for all
tillage systems.
The VESS score was only significantly correlated with RY for R2
at Flakkebjerg (Table 6). In addition, nearly significant correlations
were found for R2 at Foulum and R4 at Flakkebjerg. There was no
significant correlation between SOC and RY. Surprisingly, there
were two significant or almost significant negative correlations
between SOC and RY, i.e. for R3 at Foulum (R =
0.74) and for R2 at
Flakkebjerg (R =
0.48).