Land Use, Land-Use Change and Forestry

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3.3.2.2. Discrepancies between Actual and Reported Stock Changes

Although afforestation and reforestation ordinarily result in net carbon sequestration and deforestation results in net carbon emissions, these outcomes may not always be true in reporting under Article 3.3, depending on the definitions and carbon accounting approaches adopted. Certain definitions of ARD could result in Parties receiving "credits" (i.e., additions to their assigned amounts) for activities that cumulatively result in an increase or no change in atmospheric CO2 (type I discrepancy). Conversely, certain definitions could result in Parties receiving debits (i.e., deductions from their assigned amounts) for activities that result in reductions or no change in atmospheric CO2 (type II discrepancy). This section analyzes some of these possibilities. The discussion below is organized around the terms "forest," "reforestation," "degradation," and "deforestation":

  1. Forest. If forests are defined on the basis of a threshold for canopy cover or biomass density, a certain number (e.g., 10 percent canopy cover of trees) will be the cut-off point between forest and non-forest land. Two type I discrepancies suggest themselves:
    1. Forests with canopy cover that is greater than the threshold value could be degraded to the defined canopy cover limit, releasing a large amount of carbon to the atmosphere or transferring it to non-forest carbon pools, without carbon debit. Subsequent deforestation of the 10 percent canopy cover forests could result in an accounting of carbon loss that matches the carbon in the 10 percent canopy forest rather than in the forest that existed previously. Only the Degradation/ Aggradation and Biome definitional scenarios could avoid this problem-and only if the maximum crown cover or carbon content of vegetation at maturity is reduced. Otherwise, such degradation effects could be covered only by Article 3.4.
    2. Thinning or clear-cut harvesting operations on afforestation/reforestation lands could occur just before the first commitment period and between subsequent commitment periods to maximize carbon increments over the commitment period. This effect could be minimized through specification of contiguous commitment periods. Forest managers, however, are unlikely to base their management decisions mainly on considerations of carbon credits rather than silvicultural needs and timber market demands.
  2. Reforestation
    1. FAO scenario. If a stand is cleared and reforested between 1990 and 2008, carbon credits could be claimed even if the carbon stocks in the landscape are not increasing (type I discrepancy) (see Section 3.5.2). For a stand that is cleared and reforested between 2008 and 2012, we have to separate the three accounting options described in Section 3.2.2:
      • Activity-based approach. Carbon stock losses at the time of harvest are not accounted, nor are subsequent emissions from decaying dead organic matter. Only the accumulation of carbon in the new stand and in new dead organic matter is accounted because it results from the reforestation activity. Carbon credits could be claimed even if the carbon stocks in the landscape are not increasing (type I discrepancy) (see Section 3.5.2 for results on the landscape level).
      • Land-based approach I. The stock change over the full commitment period is measured, including stock losses during harvest, as well as delayed emissions from dead organic matter. The consequence is a large debit (except where rotation periods are below 20 years) (see Section 3.5.2). This is a type II discrepancy.
      • Land-based approach II. The carbon stock change between the beginning of the activity and the end of the commitment period is measured, including the decaying slash resulting from the harvest. In the short term, debits may be reported because of the effects of decaying slash (type II discrepancy). In the long term, credits will accrue even if stocks on the landscape are not increasing (type I discrepancy) (see Section 3.5.2 for results on the landscape level).
    2. All definitional scenarios. Assume a case where land is deforested and used for agriculture before 2008, then reforested. Credits could be claimed even though carbon stocks in the commitment period are likely to be lower than in 1990 (type I discrepancy).
    3. In the case of afforestation or reforestation between 1990 and 2008, carbon stocks can decrease in a commitment period-for example, because of harvesting or thinning. Debits would be assigned even though the afforestation or reforestation activity reduces atmospheric CO2 in the long run and carbon stocks in the commitment period likely exceed those in 1990 (type II discrepancy).
    4. FAO scenario. There can be an unbalanced treatment of different harvesting methods because partial cutting techniques do not result in reforestation under this scenario. This imbalance could result in an incentive to favor clear-cutting over other harvesting methods, possibly working against other considerations related to sustainable forest management.
  3. Degradation
    In all scenarios except Land Cover and FAO (in combination with land-based approach I), forestry activities could focus on high carbon-density forests because they can be harvested without carbon penalty as long as another forest replaces them. No carbon has to be accounted when forests of high carbon density are logged (and their large amounts of carbon released) and replaced by plantings with low carbon stocks (type I discrepancy).
  4. Deforestation
    FAO and IPCC scenarios. The forest definition contains a list of exceptions for lands that are forests without reaching the crown-cover threshold at maturity. For example, the determination of whether a new road results in deforestation would be based on the use of the road. If it is used to access forest stands for logging, it would not be considered deforestation, whereas a road that is used for transportation (such as a new highway) would be. For the purpose of determining long-term impacts on the atmosphere, this distinction is arbitrary.


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