Carbon declines along tropical forest edges correspond to heterogeneous effects on canopy structure and function

Significance Tropical forests constitute the largest terrestrial component of the global carbon budget. However, rapid agricultural expansion has left these landscapes highly fragmented, calling into question their capacity to cycle and store carbon. We utilized airborne mapping approaches that revealed changes in aboveground carbon and key aspects of ecosystem structure and function in forest edges along oil palm plantations in Malaysian Borneo. We found widespread evidence of significant changes in canopy structure and foliar traits related to light capture, growth, and productivity along forest edges that corresponded to declines in aboveground carbon. These changes underpin carbon declines that varied spatially, with far-reaching implications for the conservation of forest biodiversity and carbon stocks.