Microbial carbon utilization in a boreal lake under the combined pressures of brownification and eutrophication : insights from a field experiment
Jones, Kevin LU
; Liess, Antonia
and Sjöstedt, Johanna
LU
(2025)
In Hydrobiologia
852(3).
p.721-733
- Abstract
Climate and land use changes can increase terrestrial runoff to aquatic systems, leading to brownification and eutrophication in northern boreal lakes. Brownification may boost bacterial respiration and production, while eutrophication can enhance primary production and algal blooms. However, their combined effects on basal producers and bacterial carbon utilization are less understood. This study explores the combined impacts of the two stressors: brownification and eutrophication on microbial dynamics in Lake Bolmen. Utilizing a field mesocosm experimental design, treatments received different combinations of organic matter (OM) and inorganic nutrients to simulate predicted future scenarios. Results showed that OM additions... (More)
Climate and land use changes can increase terrestrial runoff to aquatic systems, leading to brownification and eutrophication in northern boreal lakes. Brownification may boost bacterial respiration and production, while eutrophication can enhance primary production and algal blooms. However, their combined effects on basal producers and bacterial carbon utilization are less understood. This study explores the combined impacts of the two stressors: brownification and eutrophication on microbial dynamics in Lake Bolmen. Utilizing a field mesocosm experimental design, treatments received different combinations of organic matter (OM) and inorganic nutrients to simulate predicted future scenarios. Results showed that OM additions significantly increased bacterial production and respiration, regardless of nutrient additions. Nutrient additions enhanced bacterial production but did not affect respiration. Both nutrients and OM stimulated bacterial growth efficiency. Labile carbon from DOM was the main driver of higher bacterial respiration and short-term production increases. Fluorescence data indicated that the combination of brownification and eutrophication led to higher terrestrial DOM utilization than each stressor alone. The study suggests that future boreal lakes may become more heterotrophic, thus increasing CO2 release. These findings highlight the complex interactions between DOM and nutrients and underscore the importance of considering multiple stressors in lake management and mitigation strategies.
(Less)
- author
- Jones, Kevin
LU
; Liess, Antonia
and Sjöstedt, Johanna
LU
- organization
- publishing date
- 2025
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- Brownification, Carbon utilization, Eutrophication, Microbial dynamics, Organic matter
- in
- Hydrobiologia
- volume
- 852
- issue
- 3
- pages
- 721 - 733
- publisher
- Springer Science and Business Media B.V.
- external identifiers
-
- scopus:85207033745
- ISSN
- 0018-8158
- DOI
- 10.1007/s10750-024-05718-9
- language
- English
- LU publication?
- yes
- id
- 47987802-83a3-4327-939f-324be574ca7a
- date added to LUP
- 2025-01-02 15:15:17
- date last changed
- 2025-04-04 14:38:39
@article{47987802-83a3-4327-939f-324be574ca7a,
abstract = {{<p>Climate and land use changes can increase terrestrial runoff to aquatic systems, leading to brownification and eutrophication in northern boreal lakes. Brownification may boost bacterial respiration and production, while eutrophication can enhance primary production and algal blooms. However, their combined effects on basal producers and bacterial carbon utilization are less understood. This study explores the combined impacts of the two stressors: brownification and eutrophication on microbial dynamics in Lake Bolmen. Utilizing a field mesocosm experimental design, treatments received different combinations of organic matter (OM) and inorganic nutrients to simulate predicted future scenarios. Results showed that OM additions significantly increased bacterial production and respiration, regardless of nutrient additions. Nutrient additions enhanced bacterial production but did not affect respiration. Both nutrients and OM stimulated bacterial growth efficiency. Labile carbon from DOM was the main driver of higher bacterial respiration and short-term production increases. Fluorescence data indicated that the combination of brownification and eutrophication led to higher terrestrial DOM utilization than each stressor alone. The study suggests that future boreal lakes may become more heterotrophic, thus increasing CO<sub>2</sub> release. These findings highlight the complex interactions between DOM and nutrients and underscore the importance of considering multiple stressors in lake management and mitigation strategies.</p>}},
author = {{Jones, Kevin and Liess, Antonia and Sjöstedt, Johanna}},
issn = {{0018-8158}},
keywords = {{Brownification; Carbon utilization; Eutrophication; Microbial dynamics; Organic matter}},
language = {{eng}},
number = {{3}},
pages = {{721--733}},
publisher = {{Springer Science and Business Media B.V.}},
series = {{Hydrobiologia}},
title = {{Microbial carbon utilization in a boreal lake under the combined pressures of brownification and eutrophication : insights from a field experiment}},
url = {{http://dx.doi.org/10.1007/s10750-024-05718-9}},
doi = {{10.1007/s10750-024-05718-9}},
volume = {{852}},
year = {{2025}},
}