New paper: What controls metabolism in temperate kelp forests?

We are very pleased to share a new paper led by Chang Hwa Lee and our colleagues at the Korean Institute for Ocean Science and Technology in South Korea. The paper, published in Limnology and Oceanography, investigates what controls ecosystem metabolism in temperate kelp forests.

The study was carried out together with Karl Attard, Peter Berg, Yong-Jae Baek, Jung-Ho Hyun, Dong Mun Choi, Taihun Kim, Hyun Soo Rho, Sung-Han Kim and Jae Seong Lee, bringing together expertise in aquatic eddy covariance, benthic ecology and coastal ecosystem functioning.

The team used aquatic eddy covariance (AEC) to make high-resolution, non-invasive measurements of oxygen exchange and net ecosystem metabolism within Ecklonia cava kelp forests around Jeju Island, Korea. They then combined these measurements with information on environmental conditions and kelp-canopy structure, using partial least squares regression to identify which factors were most important in controlling oxygen fluxes.

The results showed that kelp-forest metabolism is controlled by a changing interaction between light, hydrodynamics, temperature and canopy structure. During the day, variation in oxygen flux was most strongly associated with light and water movement, whereas at night the importance of canopy density and temperature increased.

These controls translated directly into changes in ecosystem metabolism. Dense, healthy kelp canopies were net productive under favourable light and hydrodynamic conditions, while elevated water temperatures and canopy degradation shifted the forests towards negative net metabolism. The study therefore shows that the functioning of kelp forests cannot be understood from kelp biomass alone—it depends on how biological structure interacts with the surrounding physical environment.

The work also demonstrates the value of AEC for resolving ecosystem-scale processes in structurally complex habitats, where conventional chamber approaches are difficult to apply. It provides a mechanistic basis for understanding the resilience of temperate kelp forests and their potential contribution to coastal carbon cycling in a changing ocean.

Reference

Lee CH, Attard KM, Berg P, Baek Y-J, Hyun J-H, Choi DM, Kim T, Rho HS, Kim SH, Lee JS (2026). Drivers of ecosystem metabolism in temperate kelp forests: A high-resolution aquatic eddy covariance study. Limnology and Oceanography 71(9). Article