Land Use, Land-Use Change and Forestry

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3.2. Definitional Scenarios and Their General Implications

There are hundreds of variations of definitions for each term (e.g., forest, afforestation, reforestation, and deforestation-see Lund, 1999, 2000) that are relevant to implementing Article 3.3 of the Kyoto Protocol (see Sections 2.2.2 and 2.2.3 for discussions of the options). Examining the implications of each variant would not be fruitful; the result would be greater confusion, rather than the clarity we are seeking. Instead, the key to exploring the implications of these definitions is to classify them into broad groupings. Each of the groupings can then be explored in terms of the strengths and weaknesses of the broad approach. Section discusses the broad categories of forest definitions (administrative, land use, and land cover), which are key to understanding the implications of different definitions of afforestation, reforestation, and deforestation. Sections 2.2.2 and 2.2.3 detail the range of plausible options for defining afforestation, reforestation, and deforestation. To facilitate discussion of the implications of different options for defining afforestation, reforestation, and deforestation, we have identified seven definitional scenarios that cover the range of definitions of forest, afforestation, reforestation, and deforestation. These scenarios are designed to provide a wide range of plausible combinations of definitions through which the implications of different options can be explored. We have explicitly avoided customizing definitions on the basis of biome type, specific management regimes, or socioeconomic conditions; instead, we explore definitions that are sufficiently robust to address diverse conditions over long periods of time.

This chapter explores how changes in land use and land cover influence carbon emissions and sequestration. The land-use status of an area of land characterizes how it is utilized to meet a human need; it represents a socioeconomic perspective on the status of the land. In contrast, land-cover characterizations of an area of land focus on what vegetation is, or is not, present. Land use-based definitions of afforestation, reforestation, and deforestation are difficult to measure and verify because the intended use of the land may not be the same as the actual use. For example, if a nation designates a piece of land as a location where forest management should take place, is that designation sufficient to define the land as forest, even in the absence of trees? Land use can be determined administratively and culturally, further complicating the employment of land use-based definitions. Land cover, on the other hand, is easier to measure and verify, but transitions from one cover class to another can easily be misinterpreted. For example, following a clear felling, the lack of a forest canopy cover could be assumed to represent deforestation, when in fact tree regeneration is taking place. The use of existing land cover as the sole basis for defining afforestation, reforestation, and deforestation would cause harvest/regeneration cycles to be accounted under Article 3.3. This situation can be avoided by instead using the potential land cover of the existing vegetation at maturity.

A variant of the land-cover approach to define a forest is based on the carbon status of the land. Such an approach acknowledges that a carbon-based definition may avoid the geographical complexities and varying intents of the existing array of definitions of a forest. Given the variability in existing inventory data, any new approach to define a forest will need to consider regional/national differences in available data. Carbon-based definitions can rely on a variety of data (e.g., timber volume, basal area, stocking density and age) from which afforestation, reforestation, and deforestation events can be determined.

As Section notes, it is not clear whether the term "direct human-induced" refers only to the ARD activities or also to the stock changes resulting from ARD activities; this issue is further discussed in Section Here we discuss the difficulty in defining direct human-induced ARD activities. Implementation of ARD would be easier and unnecessary ambiguities could be avoided if any change in vegetation resulting from a decision by a land manager to change land-use practices were regarded as DHI. Another way of dealing with "direct human-induced" is to assume that ARD activities on certain lands (e.g., managed lands) are always DHI and that activities on the remaining lands (unmanaged lands) are not DHI. This rule has at least two logical exceptions. First, if afforestation or reforestation takes place on unmanaged lands, the burden of proof for "direct human-induced" is with the party who wants to claim credits. The land would subsequently become managed land. Second, if forest regeneration does not follow a natural disturbance on managed lands (e.g., hurricanes or landslides), one must decide whether this deforestation qualifies as DHI. With a subsequent agricultural or residential use, for example, the deforestation could be regarded as DHI.

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