Effects of frozen soil on growth and longevity of fine roots of Norway spruce

Vegetative buds, needles and shoot growth of Norway spruce are affected by experimentally delayed soil thawing in the field

“…Previous studies have shown that the cold soil temperatures in spring and early summer inhibit the root function, water uptake and recovery of photosynthesis in boreal conifers even if the air temperature was high enough (Strand et al, 2002;Mellander et al, 2006;Ensminger et al, 2008;Wu et al, 2012;Repo et al, 2014). Delayed soil thawing in early summer in FROST did not hamper only tree physiology (Repo et al, 2011) but also the visible shoot growth as seen here.…”

Root and shoot phenology and root longevity of Norway spruce saplings grown at different soil temperatures

“…In interval-censored data the estimate is undefined due to non-uniqueness at certain intervals and the survival curves plotted with interval package are in these cases shown as descending slopes, and as step functions where they are defined uniquely (Fay and Shaw 2010). Mean and median longevity and their confidence intervals were estimated for short and long roots as by Repo et al (2014).…”

Connecting potential frost damage events identified from meteorological records to radial growth variation in Norway spruce and Scots pine

“…Helama et al (2013) showed that low soil temperatures as well as deep snowpack in spring were associated with lower radial growth of Scots pine. Furthermore, artificially increased soil frost, especially if soil thawing in spring is delayed, has been found to be related to higher fine-root mortality (Gaul et al 2008, Repo et al 2014, reduced starch content in needles (Repo et al 2011) and delayed growth onset (Jyske et al 2012) in Norway spruce, as well as defoliation in Scots pine (Jalkanen 1993).…”