A Comparative Study of Tree Establishment in Abandoned Pasture and Mature Forest of Eastern Amazonia

Background

This study compares seedling establishment, seed availability, seed predation, seedling herbivory, and abiotic barriers to tree establishment in recently abandoned pasture, treefall gaps, and mature forest understory in Pará State, Brazil.

Research Goals & Methods

Researchers created 3 study forest gaps by felling trees over 2 meters in height and monitored tree seedling and sprout populations for 2 years in in plots located in the 3 study systems. They examined soil seed supply through soil core collection. Seed deposition, seed predation, seedling herbivory, and abiotic factors were also measured.

Conclusions & Takeaways

Seedling establishment proved greatest in the treefall gaps and lowest in abandoned pasture.  Abandoned pasture displayed tree establishment up to 20 times lower than other sites due to  lack of tree seeds in the soil, a lack of bird and bat-dispersed seeds, and greater predation and herbivory than in mature forest.