position;
diameter at breast height (starting from 3 cm);
total height;
230 O. Ciancio et al. / Forest Ecology and Management 224 (2006) 229–234
height of first green whorl;
horizontal projection of the crown.
Increment borings were taken at breast height (1.3 m from
ground level) on 15% of the trees in all diameter classes. Age at
breast height was determined and size of the last 10 growth
rings was measured for each sample.
Standing volume and volume of the trees marked for felling
were estimated using the Italian National Forest Inventory
volume equations for Calabrian pine (MAF-ISAFA, 1988).
The current volume growth percentage P was estimated
using Schneider’s formula (Chapman and Meyer, 1949, p. 459;
Parde´, 1961, p. 288):
P ¼
K
dn
(1)
where d = tree dbh in centimetres; K = coefficient varying
between 400 and 600 with height growth rate; n = number of
growth rings in the outermost centimetre; modified as follows
(Cristofolini, 1972):
P ¼
K0s
d
(2)
where d = tree dbh in centimetres; s = size of the last 10 growth
rings (in mm); K0 = 5 for trees with dbh = 20–25 cm; 4.5 for
trees with dbh = 30–35 cm; 4 for trees with dbh = 40 cm or
more.
The average value of s was calculated for each 5 cm dbh
class, starting from dbh class 20 cm. P was estimated with [2]
for each diameter class and then its average, pm, was calculated.
Current volume growth Ic for the stand was estimated with:
Ic ¼ pmV
1
100
(3)
where V is volume of trees with dbh 17.5 cm.
position; diameter at breast height (starting from 3 cm); total height;230 O. Ciancio et al. / Forest Ecology and Management 224 (2006) 229–234 height of first green whorl; horizontal projection of the crown.Increment borings were taken at breast height (1.3 m fromground level) on 15% of the trees in all diameter classes. Age atbreast height was determined and size of the last 10 growthrings was measured for each sample.Standing volume and volume of the trees marked for fellingwere estimated using the Italian National Forest Inventoryvolume equations for Calabrian pine (MAF-ISAFA, 1988).The current volume growth percentage P was estimatedusing Schneider’s formula (Chapman and Meyer, 1949, p. 459;Parde´, 1961, p. 288):P ¼Kdn(1)where d = tree dbh in centimetres; K = coefficient varyingbetween 400 and 600 with height growth rate; n = number ofgrowth rings in the outermost centimetre; modified as follows(Cristofolini, 1972):P ¼K0sd(2)where d = tree dbh in centimetres; s = size of the last 10 growthrings (in mm); K0 = 5 for trees with dbh = 20–25 cm; 4.5 fortrees with dbh = 30–35 cm; 4 for trees with dbh = 40 cm ormore.The average value of s was calculated for each 5 cm dbhclass, starting from dbh class 20 cm. P was estimated with [2]for each diameter class and then its average, pm, was calculated.Current volume growth Ic for the stand was estimated with:Ic ¼ pmV1100(3)โดยที่ V คือ ปริมาตรของต้นไม้ที่มี dbh 17.5 cm
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