4.3.2. How Broadly or Narrowly are "Activities" Defined?
In this context, the term "broad" is used to denote an activity definition
that is essentially land- or area-based, where the net effect of all practices
that might be applied to the same area over the same time period are included
within the activity. For example, the broad activity of "cropland management"
might embrace practices such as conservation tillage, improved fertilization,
and irrigation water management. If broad definitions are applied, periodic
stock change measurements that statistically sample the area to be monitored
could be used to estimate the net effect of altered carbon emission or sink
processes. Where statistical sampling methods are used, monitoring larger areas
becomes more cost-effective because the number of samples required for a given
degree of statistical accuracy does not scale up proportionately with increased
The term "narrow" denotes an activity definition that is based on individual
practices, such as reduced tillage or irrigation water management. Where individual
practices are used as the basis for reporting, associated rates of reduced emissions
or increased sinks need to be developed through model estimates or research
plots-which in many instances are not yet available for all environmental circumstances.
Estimates of annual rates of carbon stock change could then be estimated as
a product of the area affected by the practice and the associated rate of emission
or sink (perhaps by general soil type, if needed for accuracy). Such estimates
could be verified by using other data sources or by a sampling technique that
measured soil carbon stock change on the area where the practice had been reported.
Non-CO2 GHG emission estimates could be included where appropriate (on agricultural
soils, these emissions may already be reported under the IPCC Guidelines, so
care may need to be taken to avoid double-counting).
Some implications regarding definition of activities follow:
- Activity definitions can be fairly loose.
- Lends itself to land-based stock change CO2 flux measurements; helps
minimize double-counting or undercounting.
- Non-CO2 GHG fluxes must be estimated with practice-based models or other
- Verifiable by a third party, using different methods and at a later
date, using techniques such as statistical sampling or remote sensing.
- Activity definitions critical; must be unambiguous, implementable, and
- Lends itself to activity-based model estimates of fluxes. Where multiple
activities occur on the same land area, there is a potential for double-counting.
- CO2 and non-CO2 emissions can be estimated with activity-based models.
Where more than one activity occurs on a land area, some of which are
not included in Article 3.4 accounting, stock change measures would be
- Verifiable by auditing activity statistics and independently checking
them using other data sources. Verifying where activities have occurred
in prior years may be difficult or impossible if no visible evidence remains.
Both options would require further decisions about the modalities, rules, and
guidelines necessary for implementation. Some options are discussed in Section
4.6 and in Chapter 2.
The process of selecting activities would be facilitated and made more transparent
and consistent by the development of criteria for activity selection (Section
One approach to structuring activities broadly is suggested by Figure
4-6, which indicates how broadly defined activities might be fitted into
a land-cover classification system. If such a scheme were used, every activity,
no matter how it were defined, would fit in one of the boxes in the matrix.
A national inventory based on a sampling scheme that produced statistically
reliable estimates for each land cover/land use box in the matrix could produce
national estimates of carbon stock change across all land uses and land cover
areas. Therefore, if Parties differed somewhat over the definition of an activity,
the practices carried out within the activity, or a definition of land cover
such as forest, the impact on total accounting would be minimal because the
impact would simply shift from one box in the matrix to another. If such an
approach were adopted, a full-carbon accounting system (Chapter
2) would be required, wherein each major land area and land use were sampled
on a periodic basis. Such a system is in place in some countries (national forest
inventories are one example) but may currently be infeasible for some.
Figure 4-6: Suggested land-cover, land-cover/use
change, and forestry matrix that illustrates how activities might be
identified with different land cover areas. Numbers in parentheses indicate
relevant Article in Kyoto Protocol, where apparent.
The activities reviewed in Section 4.4 are categorized
in a way that is consistent with this broadly defined approach-not to prejudge
the decisions to be taken by the Conference of Parties (COP) but to keep the
presentation to a reasonable length. For more specific information on a few
of the practices that might be considered as additional activities under the
narrow-definition approach, see the Fact Sheets at the end of the chapter.