Detection and attribution of an anomaly in terrestrial photosynthesis in Europe during the COVID-19 lockdown
(2023) In Science of the Total Environment 903.- Abstract
Carbon dioxide (CO2) uptake by plant photosynthesis, referred to as gross primary production (GPP) at the ecosystem level, is sensitive to environmental factors, including pollutant exposure, pollutant uptake, and changes in the scattering of solar shortwave irradiance (SWin) − the energy source for photosynthesis. The 2020 spring lockdown due to COVID-19 resulted in improved air quality and atmospheric transparency, providing a unique opportunity to assess the impact of air pollutants on terrestrial ecosystem functioning. However, detecting these effects can be challenging as GPP is influenced by other meteorological drivers and management practices. Based on data collected from 44 European ecosystem-scale... (More)
Carbon dioxide (CO2) uptake by plant photosynthesis, referred to as gross primary production (GPP) at the ecosystem level, is sensitive to environmental factors, including pollutant exposure, pollutant uptake, and changes in the scattering of solar shortwave irradiance (SWin) − the energy source for photosynthesis. The 2020 spring lockdown due to COVID-19 resulted in improved air quality and atmospheric transparency, providing a unique opportunity to assess the impact of air pollutants on terrestrial ecosystem functioning. However, detecting these effects can be challenging as GPP is influenced by other meteorological drivers and management practices. Based on data collected from 44 European ecosystem-scale CO2 flux monitoring stations, we observed significant changes in spring GPP at 34 sites during 2020 compared to 2015–2019. Among these, 14 sites showed an increase in GPP associated with higher SWin, 10 sites had lower GPP linked to atmospheric and soil dryness, and seven sites were subjected to management practices. The remaining three sites exhibited varying dynamics, with one experiencing colder and rainier weather resulting in lower GPP, and two showing higher GPP associated with earlier spring melts. Analysis using the regional atmospheric chemical transport model (LOTOS-EUROS) indicated that the ozone (O3) concentration remained relatively unchanged at the research sites, making it unlikely that O3 exposure was the dominant factor driving the primary production anomaly. In contrast, SWin increased by 9.4 % at 36 sites, suggesting enhanced GPP possibly due to reduced aerosol optical depth and cloudiness. Our findings indicate that air pollution and cloudiness may weaken the terrestrial carbon sink by up to 16 %. Accurate and continuous ground-based observations are crucial for detecting and attributing subtle changes in terrestrial ecosystem functioning in response to environmental and anthropogenic drivers.
(Less)
- author
- organization
- publishing date
- 2023-12-10
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- Aerosol optical depth, Air quality, COVID-19, Eddy covariance, Gross primary production, Shortwave irradiance
- in
- Science of the Total Environment
- volume
- 903
- article number
- 166149
- publisher
- Elsevier
- external identifiers
-
- pmid:37567315
- scopus:85168557799
- ISSN
- 0048-9697
- DOI
- 10.1016/j.scitotenv.2023.166149
- language
- English
- LU publication?
- yes
- id
- ee9e02dc-14ff-4a8f-a1f0-8b4a0c76ec21
- date added to LUP
- 2023-09-18 10:05:33
- date last changed
- 2024-04-19 01:10:23
@article{ee9e02dc-14ff-4a8f-a1f0-8b4a0c76ec21,
abstract = {{<p>Carbon dioxide (CO<sub>2</sub>) uptake by plant photosynthesis, referred to as gross primary production (GPP) at the ecosystem level, is sensitive to environmental factors, including pollutant exposure, pollutant uptake, and changes in the scattering of solar shortwave irradiance (SW<sub>in</sub>) − the energy source for photosynthesis. The 2020 spring lockdown due to COVID-19 resulted in improved air quality and atmospheric transparency, providing a unique opportunity to assess the impact of air pollutants on terrestrial ecosystem functioning. However, detecting these effects can be challenging as GPP is influenced by other meteorological drivers and management practices. Based on data collected from 44 European ecosystem-scale CO<sub>2</sub> flux monitoring stations, we observed significant changes in spring GPP at 34 sites during 2020 compared to 2015–2019. Among these, 14 sites showed an increase in GPP associated with higher SW<sub>in</sub>, 10 sites had lower GPP linked to atmospheric and soil dryness, and seven sites were subjected to management practices. The remaining three sites exhibited varying dynamics, with one experiencing colder and rainier weather resulting in lower GPP, and two showing higher GPP associated with earlier spring melts. Analysis using the regional atmospheric chemical transport model (LOTOS-EUROS) indicated that the ozone (O<sub>3</sub>) concentration remained relatively unchanged at the research sites, making it unlikely that O<sub>3</sub> exposure was the dominant factor driving the primary production anomaly. In contrast, SW<sub>in</sub> increased by 9.4 % at 36 sites, suggesting enhanced GPP possibly due to reduced aerosol optical depth and cloudiness. Our findings indicate that air pollution and cloudiness may weaken the terrestrial carbon sink by up to 16 %. Accurate and continuous ground-based observations are crucial for detecting and attributing subtle changes in terrestrial ecosystem functioning in response to environmental and anthropogenic drivers.</p>}},
author = {{Tang, Angela Che Ing and Flechard, Christophe R. and Arriga, Nicola and Papale, Dario and Stoy, Paul C. and Buchmann, Nina and Cuntz, Matthias and Douros, John and Fares, Silvano and Knohl, Alexander and Šigut, Ladislav and Simioni, Guillaume and Timmermans, Renske and Grünwald, Thomas and Ibrom, Andreas and Loubet, Benjamin and Mammarella, Ivan and Belelli Marchesini, Luca and Nilsson, Mats and Peichl, Matthias and Rebmann, Corinna and Schmidt, Marius and Bernhofer, Christian and Berveiller, Daniel and Cremonese, Edoardo and El-Madany, Tarek S. and Gharun, Mana and Gianelle, Damiano and Hörtnagl, Lukas and Roland, Marilyn and Varlagin, Andrej and Fu, Zheng and Heinesch, Bernard and Janssens, Ivan and Kowalska, Natalia and Dušek, Jiří and Gerosa, Giacomo and Mölder, Meelis and Tuittila, Eeva Stiina and Loustau, Denis}},
issn = {{0048-9697}},
keywords = {{Aerosol optical depth; Air quality; COVID-19; Eddy covariance; Gross primary production; Shortwave irradiance}},
language = {{eng}},
month = {{12}},
publisher = {{Elsevier}},
series = {{Science of the Total Environment}},
title = {{Detection and attribution of an anomaly in terrestrial photosynthesis in Europe during the COVID-19 lockdown}},
url = {{http://dx.doi.org/10.1016/j.scitotenv.2023.166149}},
doi = {{10.1016/j.scitotenv.2023.166149}},
volume = {{903}},
year = {{2023}},
}