Imprimir Republish

deforestation

Size of forest affects composition of tree species

Rhynchosia phaseoloides seed, one of the most plentiful species found in fragments

ALEX POPOVKIN, BAHIA, BRAZILRhynchosia phaseoloides seed, one of the most plentiful species found in fragments ALEX POPOVKIN, BAHIA, BRAZIL

The limitation on seed transport is one of the factors that alters species composition in fragmented forests. This observation, which comes from a study led by Cíntia Gomes Freitas at the Federal University of Pernambuco (UFPE), is particularly true in the Northeast state of Pernambuco. The region north of the São Francisco River, known as the Pernambuco Center of Endemism, is home to only 2% of the original Atlantic Forest, whose remnants are scattered among forest islands separated by sugar plantations. Samples of the seed sets that reached the soil in different fragments of the region indicate that the species composition of trees varies according to the fragment size and its distance from the largest source area (Acta Oecologica, November 2013). Species that germinate in sunny areas or that are dispersed by animals enjoy an advantage. Findings also show that only small seeds, which can hitch a ride with birds or bats, manage to reach the fragments that lie farther away. The dispersers of medium and large seeds – like pacas, tamarins, and sloths – apparently do not venture very far into plantations.

Republish