The total amount of C sequestered in the three simulated
systems (i.e., low intensity for pulp, high intensity for pulp, and
high intensity for pulp and saw logs) is depicted in Fig. 2. The C
sequestration is the sum of the C in the growing forest including
biomass and soil, and the C in products. These simulations that
start from an initial condition of non-forested land demonstrate
that afforestation is a positive for C sequestration no matter
what the imposed silviculture. The use of silvicultural inputs
can provide a net positive C storage in the high intensity for
pulp scenario given C increases in both soil and products, with
increases in soil being the less certain of the two. In the high
intensity for pulp and saw log scenario, even in the absence of
increased soil C storage, silviculture would provide a net
positive for C storage.
A conservative estimate of the long-term steady-state
potential for C storage under these pine silvicultural systems
can be derived utilizing a single exponential model:
y ¼ að1 eðbxÞ
Þ (1)
fit to the projected minimums in C storage after the four harvest
rotations (Fig. 2). The C sequestatration (i.e., parameter a of
Eq. (1)) is approximately 25, 81, and 122 Mg C ha1 for the
low and high intensity pulp and the high intensity pulp/sawlog
scenarios, respectively. These estimates do not include a correction
for the C emissions of silvicultural operations, which
would reduce the high intensity estimates to 69 and
110 Mg C ha1
, respectively.