Can Riparian Forest Buffers Increase Yields From Oil Palm Plantations?

Forests on tropical floodplains across Southeast Asia are being converted to oil palm plantations. Preserving natural riparian forest corridors along rivers that pass through oil palm plantations has clear benefits for ecological conservation, but these corridors (also called buffers) use land that is potentially economically valuable for agriculture. Here we examine how riparian forest buffers reduce floodplain land loss by slowing rates of riverbank erosion and lateral channel migration, thus providing the fundamentally geomorphic ecosystem service of erosion regulation. Using satellite imagery, assessments of oil palm plantation productivity, and a simplified numerical model of river channel migration, we estimate the economic value of the ecosystem service that riparian buffers provide by protecting adjacent plantation land from bank erosion. We find that cumulative economic losses from bank erosion are higher in the absence of a forest buffer than when a buffer is left intact. Our exploratory analysis suggests that retaining riparian forest buffers along tropical rivers can enhance the viability of floodplain plantations, particularly over time scales (approximately decades) commensurate with the lifetime of a typical oil palm plantation. Ecosystem services that stem directly from geomorphic processes could play a vital role in efforts to guide the long-term environmental sustainability of tropical river systems. Accounting for landscape dynamics in projections of economic returns could help bring palm oil industry goals into closer alignment with environmental conservation efforts.