Abstract
Although a global decline in the CO2 fertilization effect on vegetation productivity has recently been detected using Earth system models and satellite observations, the underlying ecological and physiological mechanisms remain poorly understood. In particular, the optimal atmospheric CO2 concentration for maximizing the CO2 fertilization effect is still unclear. In this study, we examined the optimal CO2 concentration for crop yield, plant growth, and leaf photosynthesis in soybean (Glycine max) plants utilizing environmental growth chambers to control CO2 concentration from 400 to 1,600 μmol mol-1 with intervals of 200 μmol mol-1. Our findings indicate that the optimal atmospheric CO2 concentrations for crop yield and plant growth are between 1,000 and 1,200 μmol mol-1. Similarly, the optimal CO2 concentration for leaf photosynthesis is approximately 1,200 μmol mol-1, at which point the CO2 fertilization effect reaches its maximum. Beyond this optimum, further increases in CO2 concentration not only reduce grain yield and plant biomass but also decrease leaf photosynthesis in soybeans. This demonstrates that high CO2 concentrations exceeding optimal levels have adverse effects on this critical grain crop. The physiological declines in the CO2 fertilization effect observed in soybean plants were modified by decreases in stomatal density and stomatal distribution regularity, biochemical and photochemical efficiency, and the expression level of photosynthetic genes at higher CO2 concentrations. Furthermore, this knowledge can contribute to a deeper understanding of the temporal dynamics of CO2 fertilization effects on terrestrial vegetation uptake and global carbon storage in the context of future climate change.
Abstract from the paper’s OpenAlex record, shown for indexing and research. Copyright remains with the authors or the publisher. Read at the source ↗
The text the model read, with the source record’s inline markup (italics, sub- and superscripts) rendered and its character entities decoded; quote offsets refer to the raw text.
Claims 5
Claim · model-written summary
The optimal CO2 concentration for soybean crop yield and plant growth is between 1,000 and 1,200 μmol mol-1.
- Taxon
- soybean
Glycine maxe1 - Outcome
- optimal atmospheric CO2 concentrations for crop yield and plant growthe2
- Value
- between 1,000 and 1,200 μmol mol-1e2
- Setting
- environmental growth chamberse1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e1“in soybean (Glycine max) plants utilizing environmental growth chambers”
e2“Our findings indicate that the optimal atmospheric CO2 concentrations for crop yield and plant growth are between 1,000 and 1,200 μmol mol-1”
Claim · model-written summary
The optimal CO2 concentration for soybean leaf photosynthesis is approximately 1,200 μmol mol-1.
- Taxon
- soybeanGlycine maxe1
- Outcome
- optimal CO2 concentration for leaf photosynthesise3
- Value
- approximately 1,200 μmol mol-1e3
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e1“in soybean (Glycine max) plants utilizing environmental growth chambers”
e3“the optimal CO2 concentration for leaf photosynthesis is approximately 1,200 μmol mol-1”
Claim · model-written summary
Increasing CO2 beyond the optimum reduced soybean grain yield and plant biomass.
- Taxon
- soybeanGlycine maxe1
- Treatment
- further increases in CO2 concentratione4
- Outcome
- grain yield and plant biomasse4
- Direction
- reducee4
- Comparator
- this optimume4
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e1“in soybean (Glycine max) plants utilizing environmental growth chambers”
e4“Beyond this optimum, further increases in CO2 concentration not only reduce grain yield and plant biomass but also decrease leaf photosynthesis in soybeans”
Claim · model-written summary
Increasing CO2 beyond the optimum decreased soybean leaf photosynthesis.
- Taxon
- soybeanGlycine maxe1
- Treatment
- further increases in CO2 concentratione4
- Outcome
- leaf photosynthesise4
- Direction
- decreasee4
- Comparator
- this optimume4
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e1“in soybean (Glycine max) plants utilizing environmental growth chambers”
e4“Beyond this optimum, further increases in CO2 concentration not only reduce grain yield and plant biomass but also decrease leaf photosynthesis in soybeans”
Claim · model-written summary
Decreases in stomatal density and distribution regularity, biochemical and photochemical efficiency, and photosynthetic gene expression modified the decline of the CO2 fertilization effect at high CO2.
- Taxon
- soybeanGlycine maxe1
- Gene
- photosynthetic genese5
- Outcome
- physiological declines in the CO2 fertilization effecte5
- Qualifier
- decreases in stomatal density and stomatal distribution regularitye5
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e1“in soybean (Glycine max) plants utilizing environmental growth chambers”
e5“The physiological declines in the CO2 fertilization effect observed in soybean plants were modified by decreases in stomatal density and stomatal distribution regularity, biochemical and photochemical efficiency, and the expression level of photosynthetic genes at higher CO2 concentrations”
The same questions in other papers
co2 · physiology: photosynthesis · Glycine max (soybean)Results differ
13 papers in the same direction as this paper · 50 in the opposite direction
- positive
- positive
- positive
60 papers more in this group
See all 64 papers →co2 · yield · Glycine max (soybean)Positive and negative results
9 papers in the same direction as this paper · 86 in the opposite direction
- positive
- positive
- positive
92 papers more in this group
See all 96 papers →Claims are grouped by organism, treatment and what was measured or targeted. A paper counts as positive when any of its claims in the group is positive.