Current water quality guidelines across North America and Europe do not protect lakes from salinization
(2022) In Proceedings of the National Academy of Sciences of the United States of America 119(9).- Abstract
Human-induced salinization caused by the use of road deicing salts, agricultural practices, mining operations, and climate change is a major threat to the biodiversity and functioning of freshwater ecosystems. Yet, it is unclear if freshwater ecosystems are protected from salinization by current water quality guidelines. Leveraging an experimental network of land-based and in-lake mesocosms across North America and Europe, we tested how salinization—indicated as elevated chloride (Cl2) concentration—will affect lake food webs and if two of the lowest Cl2 thresholds found globally are sufficient to protect these food webs. Our results indicated that salinization will cause substantial zooplankton mortality at the... (More)
Human-induced salinization caused by the use of road deicing salts, agricultural practices, mining operations, and climate change is a major threat to the biodiversity and functioning of freshwater ecosystems. Yet, it is unclear if freshwater ecosystems are protected from salinization by current water quality guidelines. Leveraging an experimental network of land-based and in-lake mesocosms across North America and Europe, we tested how salinization—indicated as elevated chloride (Cl2) concentration—will affect lake food webs and if two of the lowest Cl2 thresholds found globally are sufficient to protect these food webs. Our results indicated that salinization will cause substantial zooplankton mortality at the lowest Cl2 thresholds established in Canada (120 mg Cl2/L) and the United States (230 mg Cl2/L) and throughout Europe where Cl2 thresholds are generally higher. For instance, at 73% of our study sites, Cl2 concentrations that caused a ≥50% reduction in cladoceran abundance were at or below Cl2 thresholds in Canada, in the United States, and throughout Europe. Similar trends occurred for copepod and rotifer zooplankton. The loss of zooplankton triggered a cascading effect causing an increase in phytoplankton biomass at 47% of study sites. Such changes in lake food webs could alter nutrient cycling and water clarity and trigger declines in fish production. Current Cl2 thresholds across North America and Europe clearly do not adequately protect lake food webs. Water quality guidelines should be developed where they do not exist, and there is an urgent need to reassess existing guidelines to protect lake ecosystems from human-induced salinization.
(Less)
- author
- organization
- publishing date
- 2022-03
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- Biodiversity, Climate change, Environmental policy, Land use, Water quality
- in
- Proceedings of the National Academy of Sciences of the United States of America
- volume
- 119
- issue
- 9
- article number
- e2115033119
- publisher
- National Academy of Sciences
- external identifiers
-
- scopus:85124427759
- pmid:35193976
- ISSN
- 0027-8424
- DOI
- 10.1073/pnas.2115033119
- language
- English
- LU publication?
- yes
- id
- f63642e5-7da6-43d6-827e-4d9d38a6cb07
- date added to LUP
- 2022-12-28 15:07:28
- date last changed
- 2024-04-18 17:18:43
@article{f63642e5-7da6-43d6-827e-4d9d38a6cb07,
abstract = {{<p>Human-induced salinization caused by the use of road deicing salts, agricultural practices, mining operations, and climate change is a major threat to the biodiversity and functioning of freshwater ecosystems. Yet, it is unclear if freshwater ecosystems are protected from salinization by current water quality guidelines. Leveraging an experimental network of land-based and in-lake mesocosms across North America and Europe, we tested how salinization—indicated as elevated chloride (Cl<sup>2</sup>) concentration—will affect lake food webs and if two of the lowest Cl<sup>2</sup> thresholds found globally are sufficient to protect these food webs. Our results indicated that salinization will cause substantial zooplankton mortality at the lowest Cl<sup>2</sup> thresholds established in Canada (120 mg Cl<sup>2</sup>/L) and the United States (230 mg Cl<sup>2</sup>/L) and throughout Europe where Cl<sup>2</sup> thresholds are generally higher. For instance, at 73% of our study sites, Cl<sup>2</sup> concentrations that caused a ≥50% reduction in cladoceran abundance were at or below Cl<sup>2</sup> thresholds in Canada, in the United States, and throughout Europe. Similar trends occurred for copepod and rotifer zooplankton. The loss of zooplankton triggered a cascading effect causing an increase in phytoplankton biomass at 47% of study sites. Such changes in lake food webs could alter nutrient cycling and water clarity and trigger declines in fish production. Current Cl<sup>2</sup> thresholds across North America and Europe clearly do not adequately protect lake food webs. Water quality guidelines should be developed where they do not exist, and there is an urgent need to reassess existing guidelines to protect lake ecosystems from human-induced salinization.</p>}},
author = {{Hintz, William D. and Arnott, Shelley E. and Symons, Celia C. and Greco, Danielle A. and McClymont, Alexandra and Brentrup, Jennifer A. and Cañedo-Argüelles, Miguel and Derry, Alison M. and Downing, Amy L. and Gray, Derek K. and Melles, Stephanie J. and Relyea, Rick A. and Rusak, James A. and Searle, Catherine L. and Astorg, Louis and Baker, Henry K. and Beisner, Beatrix E. and Cottingham, Kathryn L. and Ersoy, Zeynep and Espinosa, Carmen and Franceschini, Jaclyn and Giorgio, Angelina T. and Göbeler, Norman and Hassal, Emily and Hébert, Marie Pier and Huynh, Mercedes and Hylander, Samuel and Jonasen, Kacie L. and Kirkwood, Andrea E. and Langenheder, Silke and Langvall, Ola and Laudon, Hjalmar and Lind, Lovisa and Lundgren, Maria and Proia, Lorenzo and Schuler, Matthew S. and Shurin, Jonathan B. and Steiner, Christopher F. and Striebel, Maren and Thibodeau, Simon and Urrutia-Cordero, Pablo and Vendrell-Puigmitja, Lidia and Weyhenmeyer, Gesa A.}},
issn = {{0027-8424}},
keywords = {{Biodiversity; Climate change; Environmental policy; Land use; Water quality}},
language = {{eng}},
number = {{9}},
publisher = {{National Academy of Sciences}},
series = {{Proceedings of the National Academy of Sciences of the United States of America}},
title = {{Current water quality guidelines across North America and Europe do not protect lakes from salinization}},
url = {{http://dx.doi.org/10.1073/pnas.2115033119}},
doi = {{10.1073/pnas.2115033119}},
volume = {{119}},
year = {{2022}},
}