sity loss, are based on an improper analysis of the logic, practice, and impact
of the range of food production systems included under the rubric of shifting
cultivation. Too often systems dominated by new migrants clearing land by
fire are assimilated with ancient traditional shifting cultivation systems. Not
enough attention has been paid to the fact that nowhere is shifting cultivation
the only food production system in the agriculture practiced by traditional
forest people. It is always complemented by hunting-and-gathering activities,
homegardens, and often complex agroforests. Overall, as this chapter has
emphasized, shifting cultivation often may create landscapes that maintain
high levels of biodiversity in general, in which some components of forest bio-
diversity probably can be conserved, especially vertebrates.
In assessing the possible contribution shifting cultivation landscapes can
make to the conservation of tropical biodiversity, it is vital to distinguish
between biodiversity in general and forest-dependent biodiversity in particu-
lar. We have tried to emphasize this distinction throughout this chapter. It is
a basic tenet of modern approaches to agriculture and natural resource man-
agement that biodiversity is a good thing. But in the humid tropics, natural
forest communities and the species that depend on them are the priority for
conservation action. In this context, biodiversity often is seen too simplisti-
cally by many observers, including social scientists (McKey 2001). Anthro-
pogenic communities—crop fields and fallows—may support, or contribute
to supporting, much biodiversity at the species and genetic levels. A great part
of tropical diversity was in place long before human influence on the charac-
teristics of tropical forests became important, however. Tropical forests are the
most biodiverse terrestrial ecosystems for reasons that are not yet fully under-
stood, and the drive to understand the creation and maintenance of their
diversity is a significant element of tropical forest research (Huston 1994;
Hubbell 2001). The “forest-dependence” of much biodiversity should be self-
evident, as should the vulnerability of this biodiversity to the high-frequency
drastic disturbance inherent in shifting cultivation and to modern tendencies
toward shorter fallows and consequently greater areas of crop fields and young
fallow vegetation in landscapes.
In conclusion, it is clear that shifting cultivation systems can play a posi-
tive role in biodiversity conservation and especially—although we have not
emphasized this comparison—a much more positive one than any modern
intensive agricultural system. Modern tropical landscapes are being increas-
ingly shaped by people, and shifting cultivation therefore is a relatively
biodiversity-friendly land use in the face of this reality. However, its contribu-
tion to biological conservation will be important only if shifting cultivation
landscapes do not become merely transient stages of frontier development, as
is often the case already. Population growth, economic policies, and govern-
188 III. The Biodiversity of Agroforestry Systems