Stratification strength and light climate explain variation in Chlorophyll a at the continental scale in a European multilake survey in a heatwave summer

0555170 - BÚ 2022 RIV US eng J - Journal Article
Fránková, Markéta … Total 193 authors
Stratification strength and light climate explain variation in Chlorophyll a at the continental scale in a European multilake survey in a heatwave summer.
Limnology and Oceanography. Roč. 66, č. 12 (2021), s. 4314-4333. ISSN 0024-3590. E-ISSN 1939-5590
Institutional support: RVO:67985939
Keywords : chlorophyll-a * climatic zones * nutrients
OECD category: Marine biology, freshwater biology, limnology
Impact factor: 5.019, year: 2021
Method of publishing: Open access
https://doi.org/10.1002/lno.11963

To determine the drivers of phytoplankton biomass, we collected standardized morphometric, physical, and biological data in 230 lakes across the Mediterranean, Continental, and Boreal climatic zones of the European continent. Multilinear regression models tested on this snapshot of mostly eutrophic lakes (median total phosphorus [TP] = 0.06 and total nitrogen [TN] = 0.7 mg L-1), and its subsets (2 depth types and 3 climatic zones), show that light climate and stratification strength were the most significant explanatory variables for chlorophyll a (Chl a) variance. TN was a significant predictor for phytoplankton biomass for shallow and continental lakes, while TP never appeared as an explanatory variable, suggesting that under high TP, light, which partially controls stratification strength, becomes limiting for phytoplankton development. Mediterranean lakes were the warmest yet most weakly stratified and had significantly less Chl a than Boreal lakes, where the temperature anomaly from the long-term average, during a summer heatwave was the highest (+4 degrees C) and showed a significant, exponential relationship with stratification strength. This European survey represents a summer snapshot of phytoplankton biomass and its drivers, and lends support that light and stratification metrics, which are both affected by climate change, are better predictors for phytoplankton biomass in nutrient-rich lakes than nutrient concentrations and surface temperature.
Permanent Link: http://hdl.handle.net/11104/0329701