Research Spotlight: Carbon declines in fragmented forests

Elsa M. Ordway & Gregory P. Asner (2020). Carbon declines along tropical forest edges correspond to heterogeneous effects on canopy structure and function. Proceedings of the National Academy of Sciences of the United States of America.



The Upshot

Using high-tech maps produced by GDCS’ Global Airborne Observatory, researchers found widespread evidence of changes to forest structure and function in forest edges along oil palm plantations in Malaysian Borneo corresponding to significant losses in both aboveground carbon storage. Since tropical forests make up the largest terrestrial share of the global carbon budget and nearly 20% are located within 100 meters of a non-forest edge, a decrease in local carbon storage for these important ecosystems has global implications. 

The Discovery

This is the first study to use advanced airborne laser-guided imaging spectroscopy to map and quantify changes to forest structure and function along forest edges and to link those changes with declines in carbon. The researchers uncovered declines in aboveground carbon averaging 22% along forest edges extending more than 100 meters into the forest interior; these edge effects worsened over time. 

The Impact

Forest conversion to oil palm plantations has long-lasting effects on forest structure and function that extends well into the interiors of forests. The results of this study will influence decisions by conservation managers to mitigate biodiversity losses associated with agricultural expansion.

The Researchers

Greg Asner is the director of the Arizona State University Center for Global Discovery and Conservation Science (GDCS). Elsa Ordway is a research fellow at GDCS and Harvard University.