Nitrogen and phosphorus colimitation of phytoplankton in Lake Baikal: Insights from a spatial survey and nutrient enrichment experiments

A comprehensive study reveals that nitrogen (N) and phosphorus (P) co-limit phytoplankton productivity in Lake Baikal during summer, challenging previous assumptions about single-nutrient limitation. Using a combination of spatial surveys across 26 sites and nutrient enrichment experiments at two trophically contrasting locations, researchers demonstrated that either N or P—or both—can limit phytoplankton growth depending on the location. While temperature positively influenced phytoplankton response in controlled incubations (with ~10% higher fluorescence at 15°C than at 10°C), it was not a significant predictor of chlorophyll a concentrations across the lake. These findings suggest that Lake Baikal, the world's most biodiverse freshwater lake, may experience increased phytoplankton productivity due to ongoing warming and nutrient loading, but the extent of this response will depend on the balance between soluble N and P inputs.

O’Donnell, D. R., Wilburn, P., Silow, E. A., Yampolsky, L. Y., & Litchman, E. (2017). Nitrogen and phosphorus colimitation of phytoplankton in Lake Baikal: Insights from a spatial survey and nutrient enrichment experiments. Limnology and Oceanography, 62(4), 1383–1392. Portico. https://doi.org/10.1002/lno.10505