Ecosystem Decay of Amazonian Forest Fragments: a 22‐Year Investigation

TLDR

The Biological Dynamics of Forest Fragments Project was originally designed to assess how fragment area influences Amazonian biotas, but it has produced insights that extend far beyond that scope. This paper synthesizes the key findings from the BDFFP, the world’s largest and longest‑running experimental study of habitat fragmentation. The synthesis is based on data collected over 22 years from the BDFFP, which systematically monitored forest fragments of varying sizes. The analysis shows that edge effects, matrix connectivity, and species avoidance of even small clearings drive fragment dynamics, while fragmentation alters species richness, invasions, forest dynamics, trophic structure, and ecological processes, and synergizes with hunting, fires, and logging to pose an even greater threat to rainforest biota.

Abstract

Abstract: We synthesized key findings from the Biological Dynamics of Forest Fragments Project, the world's largest and longest‐running experimental study of habitat fragmentation. Although initially designed to assess the influence of fragment area on Amazonian biotas, the project has yielded insights that go far beyond the original scope of the study. Results suggest that edge effects play a key role in fragment dynamics, that the matrix has a major influence on fragment connectivity and functioning, and that many Amazonian species avoid even small (<100‐m–wide) clearings. The effects of fragmentation are highly eclectic, altering species richness and abundances, species invasions, forest dynamics, the trophic structure of communities, and a variety of ecological and ecosystem processes. Moreover, forest fragmentation appears to interact synergistically with ecological changes such as hunting, fires, and logging, collectively posing an even greater threat to the rainforest biota.