Chapter 3Landscape Connectivity
and Biological Corridors
Susan G. W. LauranceNatural habitats in the tropics are being converted to agricultural land faster
than in any other biome (Whitmore 1997). The results of such rapid clearing
will be apparent in the next few decades, when most of the remaining tropi-
cal forest will occur as isolated remnants (Myers 1984). The type of habitat
that surrounds these remnants may play a crucial role in their conservation.
Adjoining habitats that are more similar to the remnants in terms of structure
and floristic composition (e.g., agroforestry lands rather than pasture or open
crop fields) will be the most beneficial to the long-term preservation of biodi-
versity.
In addition to supporting native species of plants and animals, agroforestry
areas may contribute to the conservation of biodiversity by increasing the con-
nectivity of populations, communities, and ecological processes in fragmented
landscapes. Habitats that can maintain this connectivity across the landscape
are commonly called biological corridors or simply corridors. Corridors can
consist of various types of habitat, but by definition they differ from the sur-
rounding vegetation and link habitat remnants that were once originally con-
nected (Saunders and Hobbs 1991).
When using agroforestry to increase landscape connectivity, it is important
to understand which characteristics of a corridor will make it effective for a
given organism. Because few studies have been carried out on the movement
of wildlife through agroforestry corridors, this chapter reviews the relevant lit-
erature on tropical forest corridors. It describes how rainforest animals select
and use linear habitat remnants and which features appear to be most impor-
tant for corridor effectiveness. The chapter also considers some of the relevant
research on wildlife use of agroforestry systems to discuss their usefulness in
connecting landscapes.
Landscape connectivity is a function of both the environmental features of
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