Consistent stoichiometric long-term relationships between nutrients and chlorophyll-a across shallow lakes

Research output: Contribution to journalResearch articleContributedpeer-review

Contributors

  • Daniel Graeber - , Helmholtz Centre for Environmental Research (Author)
  • Mark J. McCarthy - , Estonian University of Life Sciences (Author)
  • Tom Shatwell - , Helmholtz Centre for Environmental Research (Author)
  • Dietrich Borchardt - , Helmholtz Centre for Environmental Research (Author)
  • Erik Jeppesen - , Aarhus University, Sino-Danish Education and Research Centre, Middle East Technical University, Yunnan University (Author)
  • Martin Søndergaard - , Aarhus University, Sino-Danish Education and Research Centre (Author)
  • Torben L. Lauridsen - , Aarhus University, Sino-Danish Education and Research Centre (Author)
  • Thomas A. Davidson - , Aarhus University (Author)

Abstract

Aquatic ecosystems are threatened by eutrophication from nutrient pollution. In lakes, eutrophication causes a plethora of deleterious effects, such as harmful algal blooms, fish kills and increased methane emissions. However, lake-specific responses to nutrient changes are highly variable, complicating eutrophication management. These lake-specific responses could result from short-term stochastic drivers overshadowing lake-independent, long-term relationships between phytoplankton and nutrients. Here, we show that strong stoichiometric long-term relationships exist between nutrients and chlorophyll a (Chla) for 5-year simple moving averages (SMA, median R² = 0.87) along a gradient of total nitrogen to total phosphorus (TN:TP) ratios. These stoichiometric relationships are consistent across 159 shallow lakes (defined as average depth < 6 m) from a cross-continental, open-access database. We calculate 5-year SMA residuals to assess short-term variability and find substantial short-term Chla variation which is weakly related to nutrient concentrations (median R² = 0.12). With shallow lakes representing 89% of the world’s lakes, the identified stoichiometric long-term relationships can globally improve quantitative nutrient management in both lakes and their catchments through a nutrient-ratio-based strategy.

Details

Original languageEnglish
Article number809
JournalNature communications
Volume15
Issue number1
Publication statusPublished - Dec 2024
Peer-reviewedYes
Externally publishedYes

External IDs

PubMed 38280872