ABSTRACT
The woody understorey of two Atlantic Rainforest remnants in Igarassu, Pernambuco, were studied (Pezinho Forest - MPZ, 27ha and BR Forest - MBR, 99ha), aiming at assessing physiognomy, structure and edge influence over the vegetation. Ten 5 × 5m plots were set up at the edge (0-50m from forest margin), interior I (50- 100m) and interior II (>300m) of each fragment. In MPZ, 1152 individuals and 65 species were recorded (H'=3.186 nats/ ind.): 36, 42 and 39 on the edge, interior I and II, respectively. Structural differences were found between habitats, individualizing the edge, although little physiognomic differences were encountered. In MBR, 1405 individuals and 67 species were registered (H'=3,068 nats/ind.): 37 species in the edge, 36 and 48 in Interior I and II. Physiognomic and structural differences mainly distinguished the Interior II. Floristically, a similarity of 45.5% was found between fragments, which were structurally different: in MPZ, there were more understorey-typical individuals and less rare species; MBR retained greater species richness, more rare species and higher regeneration of canopy species. In both, there was an understorey differentiation at the edges, more evident in the smaller fragment, and, in the larger remnant, differentiation of interior II.
Key words:
edge effect; fragmentation; regeneration