5.4.1.1. Identification of Carbon Pools
Possible criteria affecting the selection of carbon pools to inventory and
monitor are the type of project; the size of the pool, its rate of change, and
its direction of change; the availability of appropriate methods; the cost to
measure; and attainable accuracy and precision (MacDicken, 1997a,b). A selective
or partial accounting system can be used; such a system must include all pools
expected to decrease and a choice of pools expected to increase as a result
of the project (Hamburg, 2000). Only measured (or estimated from a measured
parameter) and monitored pools are incorporated into the calculation of GHG
benefits. Carbon benefits are calculated as the net differences between selected
pools for the with- and without-project baseline conditions on the same piece
of land over a specified time period.
The major carbon pools in LULUCF projects are live biomass, dead biomass, soil,
and wood products; each of these pools can be subdivided further (e.g., live
biomass may include leaves, twigs, branches, stems, coarse and fine roots of
trees, herbaceous plants, shrubs, and vines-see Chapter 2
for further details). Table 5-7 illustrates how decisions
about which pools to choose for quantification and monitoring may be made for
different types of LULUCF projects. Accurately and precisely measuring soil
carbon pools presents several challenges; of the projects listed in Table
5-7, however, the soil carbon pool need be measured in only two cases (Y).
|
Table 5-7: Decision matrix of main carbon pools
for examples of land-use and forestry projects to illustrate selection of pools
to quantify and monitor. Y = yes, indicating that the change in this pool is likely
to be large and should be measured. R = recommended, indicating that the change
in the pool could be significant but measuring costs to achieve desired levels
of precision could be high. N = no, indicating that the change is likely small
to none thus not necessary to measure this pool. M indicates that the change in
this pool may need to be measured depending on forest type and/or management intensity
of the project.
|
|
| |
Carbon Pools
|
| Project Type |
Live Biomass
|
Dead Biomass
|
Soil
|
Wood
Products
|
|
Trees
|
Herbaceous
|
Roots
|
Fine
|
Coarse
|
|
| Avoid Emissions |
|
|
|
|
|
|
|
| - Stop deforestation |
Y
|
M
|
R
|
M
|
Y
|
R
|
M
|
| - Reduced-impact logging |
Y
|
M
|
R
|
M
|
Y
|
M
|
M
|
| - Improved forest management |
Y
|
M
|
R
|
M
|
Y
|
M
|
Y
|
| |
|
|
|
|
|
|
|
| Sequester Carbon |
|
|
|
|
|
|
|
| - Plantations |
Y
|
N
|
R
|
M
|
M
|
R
|
Y
|
| - Agroforestry |
Y
|
Y
|
M
|
N
|
N
|
R
|
M
|
| - Soil carbon management |
N
|
N
|
M
|
M
|
N
|
Y
|
N
|
| |
|
|
|
|
|
|
|
| Carbon Substitution |
|
|
|
|
|
|
|
| - Short-rotation energy plantations |
Y
|
N
|
M
|
N
|
N
|
Y
|
*
|
|
|
* Stores carbon in unburned fossil fuels.
|
|
Table 5-8 includes a selection of projects and their
measured or estimated carbon pools (for other project details, see Table
5-1 and Box 5-1). Although soil carbon is measured
in two of the emission avoidance projects, using these data for calculating
the carbon benefits could be problematic. In the NKCAP, for example, the soil
carbon benefits from averted deforestation could be calculated as the difference
between the soil carbon in the project area and soil carbon in a nearby reference
area. Without careful selection of the reference site, its average soil carbon
could be higher or lower than the average of the project area solely because
of variability in soil characteristics rather than human management. Thus, simply
subtracting the forest soil carbon from the agriculture soil carbon would give
erroneous carbon offsets.
|
Table 5-8: Main carbon pools measured in a selection
of forest-based pilot carbon-offset projects. Y means the pool was measured, N
means it was not measured, and E means it was estimated from field measurements
and literature data.
|
|
| Project Type |
Carbon Pools
|
|
Trees
|
Herbaceous/Understory
|
Roots
|
Dead Fine
|
Coarse
|
Soil
|
Wood Products
|
|
| Avoid Emissions |
|
|
|
|
|
|
|
| - Noel Kempff Climate |
Y
|
Y
|
E
|
Y
|
Y
|
Y
|
E
|
| Action Project, Boliviaa |
|
|
|
|
|
|
|
| - Reduced-Impact Logging, |
Y
|
Y
|
Y
|
Y
|
Y
|
N
|
N
|
| Sabah, Malaysiab |
|
|
|
|
|
|
|
- Rio Bravo Carbon
|
Y
|
Y
|
E
|
Y
|
N
|
Y
|
N
|
| Sequestration Projectc |
|
|
|
|
|
|
|
| |
|
|
|
|
|
|
|
| Sequester Carbon |
|
|
|
|
|
|
|
| - Farm Forestry Scolel Te Pilot |
Y
|
N
|
N
|
N
|
N
|
Y
|
N
|
| Project, Chiapas, Mexicod |
|
|
|
|
|
|
|
| - FACE, Malaysiae |
Y
|
Y
|
E
|
Y
|
Y
|
N
|
N
|
| |
|
|
|
|
|
|
|
| Multi-Component |
|
|
|
|
|
|
|
| - PAP/PFP, Costa Ricaf |
E
|
E
|
E
|
N
|
N
|
N
|
N
|
| - Guaraqueçaba Climate |
Y
|
Y
|
E
|
Y
|
Y
|
N
|
N
|
| Action Project, Brazilg |
|
|
|
|
|
|
|
|
a Brown et al. (2000).
b Pinard and Putz (1997).
c Programme for Belize (1997).
d de Jong et al. (1997).
e Moura-Costa (1993 1996a).
f SGS (1998).
g Brown et al. (1999b).
|
|
|