Citation: Wang, P.; Wang, S.;Chen,
B.; Amir, M.; Wang, L.; Chen, J.; Ma,
L.; Wang, X.; Liu, Y.; Zhu, K. Light
and Water Conditions Co-Regulated
Stomata and Leaf Relative Uptake
Rate (LRU) during Photosynthesis
and COS Assimilation: A
Meta-Analysis. Sustainability 2022, 14,
2840. https://doi.org/10.3390/
su14052840
Academic Editor: Antonio
Caggiano
Received: 27 January 2022
Accepted: 22 February 2022
Published: 28 February 2022
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sustainability
Article
Light and Water Conditions Co-Regulated Stomata and Leaf
Relative Uptake Rate (LRU) during Photosynthesis and COS
Assimilation: A Meta-Analysis
Pengyuan Wang
1,2
, Shaoqiang Wang
1,2,3,
*, Bin Chen
1,2
, Muhammad Amir
1,2
, Lei Wang
4
,
Jinghua Chen
1,2
, Li Ma
1,2
, Xiaobo Wang
1,2
, Yuanyuan Liu
1,2
and Kai Zhu
1,2
1
Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and
Natural Resources Research, Chinese Academy of Sciences (CAS), Beijing 100101, China;
wangpy.19b@igsnrr.ac.cn (P.W.); chenbin@igsnrr.ac.cn (B.C.); mamir2019@igsnrr.ac.cn (M.A.);
chenjh.14b@igsnrr.ac.cn (J.C.); mali.16b@igsnrr.ac.cn (L.M.); wxbwxb1995@163.com (X.W.);
liuyuanyuan182@mails.ucas.edu.cn (Y.L.); zhuk.20b@igsnrr.ac.cn (K.Z.)
2
School of Resources and Environment, University of Chinese Academy of Sciences (UCAS),
Beijing 100049, China
3
School of Geography and Information Engineering, China University of Geosciences (Wuhan),
Wuhan 430074, China
4
Hefei Institute of Physical Science, Chinese Academy of Sciences (CAS), Hefei 230031, China;
wanglei@aiofm.ac.cn
* Correspondence: sqwang@igsnrr.ac.cn
Abstract: As a trace gas involved in hydration during plant photosynthesis, carbonyl sulfide (COS)
and its leaf relative uptake rate (LRU) is used to reduce the uncertainties in simulations of gross pri-
mary productivity (GPP). In this study, 101 independent observations were collected from 22 studies.
We extracted the LRU, stomatal conductance (g
s
), canopy COS and carbon dioxide (CO
2
) fluxes, and
relevant environmental conditions (i.e., light, temperature, and humidity), as well as the atmospheric
COS and CO
2
concentrations (C
a,COS
and C
a,CO2
). Although no evidence was found showing that g
s
regulates LRU, they responded in opposite ways to diurnal variations of environmental conditions
in both mixed forests (LRU: Hedges’d = −0.901, LnRR = −0.189; g
s
: Hedges’d = 0.785, LnRR = 0.739)
and croplands dominated by C3 plants (Hedges’d = −0.491, LnRR = −0.371; g
s
: Hedges’d = 1.066,
LnRR = 0.322). In this process, the stomata play an important role in COS assimilation (R
2
= 0.340,
p = 0.020) and further influence the interrelationship of COS and CO
2
fluxes (R
2
= 0.650, p = 0.000).
Slight increases in light intensity (R
2
= 1, p = 0.002) and atmospheric drought (R
2
= 0.885, p = 0.005)
also decreased the LRU. The LRU saturation points of C
a,COS
and C
a,CO
2
were observed when
ΔC
a,COS
≈ 13 ppt (R
2
= 0.580, p = 0.050) or ΔC
a,CO
2
≈−18 ppm (R
2
= 0.970, p = 0.003). This study
concluded that during plant photosynthesis and COS assimilation, light and water conditions co-
regulated the stomata and LRU.
Keywords: meta-analysis; carbonyl sulfide (COS); carbon dioxide (CO
2
); leaf relative uptake rates
(LRU); stomatal conductance; environmental conditions
1. Introduction
1.1. Global Change and the Terrestrial Carbon Fixation
Global industrialization has caused the enrichment of atmospheric greenhouse gases
(GHGs) globally [1]. In the atmosphere, GHGs have changed the process of radiation
transmission [2]; further, more radiation is being trapped in the atmosphere [3,4]. The
long-lived GHGs have dominated 47% of global warming, in particular, CO
2
takes up
80% of this increase alone [5]. In this context, terrestrial and oceanic carbon sinks have
been found to increase continuously over the last 60 years [6–9]. The terrestrial ecosystem
responds to climate variability and climate change [10–12]. Global warming and land-cover
Sustainability 2022, 14, 2840. https://doi.org/10.3390/su14052840 https://www.mdpi.com/journal/sustainability