Proceedings of the Workshop - Georg-August-Universität Göttingen

slight alteration level in the mature forest area that produces 0.111 Mt C/ha of loss in
the carbon stock per area unit that possess more above ground biomass (Table 9).
Table 8. Carbon fixation quantity (Mton C) in native forest according to the type of
canopy closure and forest structure
Structure
Year
Very Dense Dense Open
(100%-75%) (75%-50%) (50%-25%)
Mature Forest
1993 26652.94 4572.44 1258.89
2007 25867.28 4424.70 1242.79
Second-growth Forest
1993 23126.32 10557.35 2734.36
2007 21908.32 10088.60 2626.33
Mature / Second-growth Forest
1993 7171.23 1891.27 565.51
2007 6702.64 1812.15 544.47
Table 9. Change in the stock (Mton C) for the cover of native forests.
Type of structure Very dense Dense Open Loss (Mton C)/ha
Mature Forest -785.66 -147.74 -16.10 -0.111 %
Second-growth Forest -1218.00 -468.75 -108.03 -0.054 %
Mature/ Second-growth Forest -468.59 -79.13 -21.04 -0.102 %
Graphic 3. Change in the carbon stock for a period of 14 years in south central Chile.
Table 9 indicates the forests’ general diminution in carbon stock. The amounts
are negatives for the sites with very dense, dense, and open cover in the mature forest,
second-growth forest, and mature/second-growth forest structures. Only 1.8% of the
mature forest was transferred to a secondary structure as second-growth forest. These
occur for two types of alterations, anthropic or natural, in which case it is not possible to
determine the degradation root. We should consider that the native forests have
already some alteration degree and previous degradation since they were exposed to
selective harvesting in the past; therefore, the degradation probabilities as causes of
product extraction are lower (Bertran & Morales, 2008).
It was determined that the forest corresponding to second-growth forest
structure has total stock values of 10000 Mton C for the dense cover, and 2600 Mton C
for the open cover (Table 8). These values are greater than the rest of the forest
structures for the same canopy cover. This takes place because the native secondgrowth
forest covers the most surface area of the region.
In general, this structure presented the greatest stock decrease, between 1218
and 108.03 Mton C for very dense and open covers (Table 9) respectively. It is
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