Edge Effects in Central Amazonian Forest Fragments

• DOI: 10.2307/1940897
• Publication Date: 2006-05-09T15:34:26Z
• Authors: Jay R. Malcolm
• Keywords: Understory

Current descriptive models of edge effects describe little more than the relationship between perimeter and area. A realistic model, one that incorporates additive nature effects, is presented tested. The total effect at a location within patch modelled as sum points along edges patch, weighted by distances from to location. At four sites in central Amazon °80 km north Manaus, Brazil, I measured vertical stratification foliage three primary forest habitats: (1) continuous close linear edges, (2) 10—ha fragments, (3) 1—ha fragments. Foliage thickness (foliage density line) was scored six height intervals (0—2, 2—5, 5—10, 10—20, 20—30, 30—40 m). With decreasing distance edge, understory (0—5 m) increased overstory (10—30 decreased, agreed with predicted model. Using parameter estimates obtained best “fit” model these data 1— fragments predicted. varied extensively among but quite closely performed better curvilinear non—additive one.