Agroforestry and Biodiversity Conservation in Tropical Landscapes

Introduction: The Role of

Agroforestry in Biodiversity Conservation

in Tropical Landscapes

Götz Schroth, Gustavo A. B. da Fonseca, Celia A. Harvey,

Heraldo L. Vasconcelos, Claude Gascon, and Anne-Marie N. Izac

In the tropics, as in the temperate zone, agricultural land use almost always takes
place at the expense of natural ecosystems and their biodiversity. For several mil-
lennia, humans have attempted to domesticate tropical ecosystems and land-
scapes in order to channel a larger share of primary production toward their own
consumption. Initially they often did this in a subtle way by enriching forests
close to campsites with useful plant species or clearing small patches of forest or
savanna with primitive tools and fire. But as human populations and their tech-
nological capabilities increased and markets for tropical agricultural products
developed, the impact of agriculture on tropical ecosystems and landscapes
became more dramatic. The devastation of the Brazilian coastal rainforest by
European immigrants for growing sugarcane, coffee, cocoa, and other com-
modities is but one example of wasteful agricultural use of a biodiversity-rich
ecosystem in the tropics (Dean 1995). With the rapid increase of tropical pop-
ulations and global markets in the twentieth century, human impacts on tropi-
cal and global ecosystems have reached new dimensions (McNeill 2000).
However, the degree to which tropical ecosystems and landscapes have
been transformed through human land use differs dramatically between
regions. Depending on their natural resource base, population density, land
use history, proximity to urban markets, and many other factors, human-
dominated tropical landscapes may be areas completely devoid of tree cover,
largely forested mosaics of extractively used primary and secondary forests
with small clearings for annual crops, homegardens, and habitations, or any-
thing in between. The concept of agroforestry embraces many intermediate-
intensity land use forms, where trees still cover a significant proportion of the
landscape and influence microclimate, matter and energy cycles, and biotic
processes.

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