When the inclusion of additional activities under Article 3.4 is considered,
it is possible to interpret "activity" broadly (e.g., cropland management)
or narrowly (e.g., change in tillage method, fertilization, or cover crops).
Under either interpretation, it is, in principle, possible to choose either
a land-based or an activity-based method of carbon accounting or a combination
of both (see Section 4). These combined choices will affect the accuracy,
feasibility, cost, transparency, and verifiability of monitoring and reporting
of emissions and removals, including non-CO2 greenhouse gases, and attributing
them to specific activities. [2.3.2.2, 4.3.1,
4.3.2]
The term "broad activity" means an activity definition that is land- or
area-based, where the net effect of all practices applied within the same
area are included. A broad activity definition is likely to require land-based
accounting (see paragraph 34). This definitional approach would capture the
net emission or removal effects of practices that deplete carbon stocks as
well as those that increase removals by sinks. Broad activity definitions,
particularly in cases where land-use change is involved, may make it difficult
to separate human-induced changes from naturally induced changes. [2.3.2,
4.3.2]
The narrow definition of "activity" is based on individual practices, such
as reduced tillage or irrigation water management. The narrow definition may
lend itself to activity-based accounting, but land-based accounting is also
possible. Under activity-based accounting, discrete definitions and associated
rates of emissions or removals are needed for each individual practice. Narrow
definitions raise the potential for multiple activities to occur on a single
land area, raising accounting issues (see paragraph 33). Narrow activity definitions
may facilitate the separation of human-induced changes from natural influences
(see paragraph 45). [4.2.1, 4.3.2,
4.3.4]
