J. Uuttera et al., THE STRUCTURE OF FOREST STANDS IN VIRGIN AND MANAGED PEATLANDS - A COMPARISON BETWEEN FINNISH AND RUSSIAN KARELIA, Forest ecology and management, 96(1-2), 1997, pp. 125-138
This study investigated the changes caused by management, including dr
ainage and thinnings, in peatland forest stand structure. Drained peat
land sites in Finnish North Karelia were compared within the same type
groups and nutrient status levels of virgin peatlands in the Republic
of Karelia, the Russian Federation. The Variables studied, which depi
ct stand structure variation, included: (1) the diameter of the median
tree; (2) the range of sampled diameters; (3) the basal area of the s
tand; (4) the estimated number of tree storeys; and (5) the number of
the tree species. The number of tree storeys was determined through no
n-parametric Kernel estimation. Over a long duration, management smoot
hs the natural multi-modal structure of virgin peatland stocking by de
creasing the variation in size-distribution. Management also changes t
he natural tree species dynamics on peatland sites by providing a comp
etitive advantage to the tree species, which adjust best to the change
d growing conditions. These species begin to dominate the habitat and
reduce the species diversity. The effect of recent thinnings and clean
ing cuttings on the forest structure is dependent upon fertility of th
e site and the stage of the forest stock at the moment of silvicultura
l operation. Cleaning cuttings may have also an increasing effect on t
he structural diversity of peatland forest stand. (C) 1997 Elsevier Sc
ience B.V.