ical forests in Indonesian Borneo (Curran et al. 1999), peninsular Malaysia
(Peters 2001), and eastern Amazonia (Cochrane and Laurance 2002).
Matrix Effects
The matrix is the mosaic of modified habitats, such as pastures, crops, planta-
tions, and secondary forest, that surrounds habitat fragments (Forman 1995).
Different matrix habitats can have a major influence on the ecology of frag-
mented forests. In the Amazon, forest fragments surrounded by 5- to 10-m-tall
regrowth forest experienced less intensive changes in microclimate (Didham
and Lawton 1999) and had lower edge-related tree mortality (Mesquita et al.
1999) than did similar fragments adjoined by cattle pastures. Edge avoidance
by mixed-species bird flocks was also lower when fragments were surrounded
by regrowth forest rather than cattle pastures (Stouffer and Bierregaard 1995b).
40 I. Conservation Biology and Landscape Ecology in the Tropics
Figure 2.2. Penetration distances of different edge effects into Amazonian forest
remnants (after Laurance et al. 2002). PAR = Photosynthetically active radiation.