CANCOR Analysis
The CANCOR analysis revealed positive and negative adaptive loci that
were correlated (|r |=0.25) with phenotypic
traits (Fig.1). Ten adaptive loci with positive phenotypic effects on
height were found but no adaptive loci for positive increases in DBH
being discovered. Incidentally, two of these loci for height were
identified in the GAPIT analyse. The two loci were associated with
environmental traits for maximum solar radiation and forest fire risk
(aridity-based parameters). Twenty-six loci were associated with a
reduction in height and one locus was associated with a reduction in
DBH. One of these loci was shared between DBH and height and none of
these loci were shared between CANCOR and GAPIT . From the environmental
analyses, 121 loci were positively adaptive towards one or more
variables. Of these 62 were shared between the GAPIT and CANCOR
analyses. 131 loci were negatively correlated with to one or more
environmental parameters. Zero of these negatively adaptive loci were
shared with the GAPIT analyses.
Association between environmental and phenotypic traits was defined as
sharing a position in the first two canonical dimensions. All positive
associations were relating to height. Four associations were due to
maximum solar radiation (max_srad) which is typical for spruce trees to
grow taller in the presence of solar radiation, however, these loci may
indicate more efficient use of solar radiation. Two were towards and two
involved precipitation seasonality. Interestingly one association linked
height increases with forest fire risk (aridity-based parameters) which
indicated aridity adaptations. There were twenty-six loci associated
with a negative reduction in height. Of these, 15 loci were associated
with maximum or mean snow cover indicating adaptive reduction in size to
cope with high snow cover. 11 loci were involved with minimum or mean
solar radiation (mean srad).
There were approximately two environmental gradients discovered in the
environmental analyses (Fig.2). The first, and main cluster, is found
between quadrants 2 and 3 with adaptive loci being found for solar
radiation (mean srad, min_srad, max_srad), aridity (forest fire,
isothemality, precipitation seasonality, precipitation of driest month)
and temperature extremes (max temp, min temp) (Fig.2a). The second
cluster, which was smaller, is found between quadrants one and four with
adaptive loci for snowfall (min snow cover, mean snow cover, max snow
cover) and temperature ranges (temperature seasonality, temperature
annual range) being discovered (Fig.2a). Height is mainly affected by
the first cluster and DBH is located in quadrant three but is not
directly affected by any environmental parameters (Fig.2b).