1. As the role of forestry-based options for reducing or mitigating greenho
use gas emissions is debated by policymakers, there is a need to inform the
debate by synthesizing existing information on carbon dynamics in tropical
forest systems and by applying this information to a range of possible int
erventions in forestry.
2. To investigate the consequences of reductions in logging damage for ecos
ystem carbon storage, we constructed a model to simulate changes in biomass
and carbon pools following logging of primary dipterocarp forests in south
-east Asia. We adapted a physiologically driven tree-based model of natural
forest gap dynamics (FORMIX) to simulate forest recovery following logging
.
3. Following selective logging, simulated ecosystem carbon storage declined
from prelogging levels (213 Mg C ha(-1)) to a low of 97 Mg C ha(-1), 7 yea
rs after logging. Carbon storage in biomass approached prelogging levels ab
out 120 years after logging.
4. The relationship between fatal stand damage and ecosystem carbon storage
was not linear, with biomass recovery following logging severely limited b
y 50-60% stand damage.
5. Results from simulations suggest that when 20-50% of the stand is killed
during logging, replacing persistent forest species with pioneer tree spec
ies can reduce the site's potential for carbon storage by 15-26% over 40-60
years.
6. Reducing fatal damage from 40% to 20% of the residual stand, as was the
case with a pilot project in Malaysia, was associated with an increase of 3
6 Mg C ha(-1) in mean carbon storage over 60 years.
7. Efforts to monitor and verify the benefits, either through carbon seques
tration in new growth or carbon retention in existing biomass, of offset pr
ojects involving tropical forests and natural forest management should focu
s on above-ground biomass, particularly the large trees. Selection of the m
ost appropriate allometric equations for a site and species is important be
cause of their influence on biomass estimates.