Tree and shrub seed dispersal in pastures: The importance of rainforest trees outside forest fragments

Abstract

Abstract Forest recovery in tropical pastures is limited by seed dispersal, mainly because the seed dispersers of woody plants avoid deforested areas. In Los Tuxtlas, Mexico, we fenced in isolated fig trees that had been left to provide shade in pastures. We monitored seed deposition under their canopies over a year and sampled the established vegetation after 3 y. Dispersal distances were estimated for captured seeds and established plants, assuming that the nearest conspecific adult rooted within 75 m of the fig tree was the mother. Seventy tree and shrub species were captured in seed rain, with a cumulative density of 833 seeds·m−2·y−1. After 3 y, 77 species of trees and shrubs had established (density: 4.0 plants·m−2). Seeds < 7 mm in diameter were frequently dispersed over distances greater than 75 m across the pasture. Larger seeds were dispersed over shorter distances and in much lower numbers, but once they had arrived at the isolated fig trees, germination and establishment success was higher tha...