Agroforestry and Biodiversity Conservation in Tropical Landscapes

Chapter 8

The Biodiversity and

Conservation Potential of Shifting

Cultivation Landscapes

Bryan Finegan and Robert Nasi

The most commonly used definitions of shifting cultivation (or swidden agri-
culture) are based on the work of Conklin (1957) and define it as any agricul-
tural system in which the fields are cleared and cultivated for periods shorter
than those over which they are fallowed. A more dynamic approach emerged
in more recent works, with McGrath (1987) defining shifting cultivation as “a
strategy of resource management in which fields are shifted in order to exploit
the energy and nutrient capital of the vegetation-soil complex of the future site
(p. 221).” Watters (1971) summarizes the principal characteristics that define
shifting cultivation as it is practiced in the tropics: the shift between fields
rather than between crops on the same field, short (1- to 3-year) cropping
periods alternating with longer fallow periods (4–60 years), cutting and burn-
ing of the fallow vegetation at the beginning of each cropping period, and the
almost exclusive use of human energy in land management operations. It is the
alternation on the same site of crops and fallow vegetation dominated by
woody plants that permits the definition of shifting cultivation as an agro-
forestry land use.
Shifting cultivation creates unique landscapes composed of a dynamic
patchwork of crop fields, fallows of various ages, secondary forest derived from
fallows, and remnants of the original vegetation. Crop fields and old second-
ary forests are clearly defined communities (Finegan 1992; Smith et al. 1997),
but scientists from different disciplines may see fallows in different ways. In a
forestry or ecological context, fallow communities are seen as secondary vege-
tation within a framework of dynamic relationships between vegetation types,
centered on primary or old-growth vegetation. The definition of “forest fallow
systems” used by FAO (1998) typifies this forest-centered approach, referring
to “complexes of woody vegetation deriving from the clearing of forest for

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