Report - ICP Forests

34 2. Large Scale Crown Condition Surveys
2.2.2.4 Picea abies
In both time series, Picea abies constitutes
the second largest share of trees behind
Pinus sylvestris. In the period 1991-2009,
the largest share of damaged trees was
registered in 1997 (39.1%). It decreased to
29.0% in 2006 and remained on the same
level until 2009. In the sample based on the
period 1998 to 2009 the distribution of trees
within the different damage classes
remained rather unchanged. (Figure 2.2.2.4-
1). This unchanged general trend is the
result of differing trends on plots in the
various forest types as has been shown in
previous reports.
The map shows that in Belarus and in
south-eastern Norway plots with decreasing
defoliation prevail. In Czech Republic there
are more plots with an increase than plots
with a decrease. (Figure 2.2.2.4-2).
N trees 0-10% >10-25% >25%
1991 15088 25.9 37.4 36.6
1992 12296 26.8 37.4 35.8
1993 12473 28.1 37.6 34.4
1994 12810 26.3 35.7 38.0
1995 14476 28.9 33.7 37.4
1996 14435 29.4 32.0 38.7
1997 14230 27.0 33.9 39.1
1998 13729 32.2 36.6 31.3
1999 14129 33.2 36.8 30.1
2000 14175 31.3 38.0 30.7
2001 13899 30.3 39.7 30.0
2002 13936 29.2 39.4 31.3
2003 13930 28.7 40.8 30.5
2004 14365 27.1 38.3 34.6
2005 13915 28.1 40.3 31.6
2006 11914 33.9 37.2 29.0
2007 11404 30.6 39.5 30.0
2008 10991 30.6 39.2 30.2
2009 10283 30.8 38.7 30.5
N trees 0-10% >10-25% >25%
1998 17465 34.0 36.1 29.9
1999 17862 35.1 36.7 28.3
2000 17832 33.1 38.3 28.7
2001 17575 32.6 39.4 27.9
2002 17631 33.2 39.1 27.7
2003 17738 32.6 40.3 27.1
2004 18273 32.8 37.4 29.9
2005 17751 33.8 38.5 27.6
2006 15843 39.2 36.3 24.5
2007 15557 37.3 37.5 25.2
2008 15325 37.4 37.3 25.3
2009 14893 38.5 36.8 24.7
Percent of trees
100
80
60
40
0-10% (91-09)
>25% (91-09)
0-10% (98-09)
>25% (98-09)
20
0
1991
1993
1995
1997
1999
Year
Figure 2.2.2.4-1: Shares of trees of defoliation 0-10%
and >25% in two periods (1991-2009 and 1998-2009).
2001
2003
2005
2007
2009