No growth stimulation of tropical trees by 150 years of CO2 fertilization but water-use efficiency increased

Elevated atmospheric CO2 concentrations ([eCO2]) and soil water deficits significantly influence gas exchange in plant leaves, affecting the carbon-water cycle in terrestrial ecosystems. However, it remains unclear how the soil water deficit modulates the plant CO2 fertilization effect, especially for gas exchange and leaf-level water use efficiency (WUE). Here, we synthesized a comprehensive dataset including 554 observations from 54 individual studies and quantified the responses for leaf gas exchange induced by e[CO2] under water deficit. Moreover, we investigated the contribution of plant net photosynthesis rate (Pn) and transpiration rates (Tr) toward WUE in water deficit conditions and e[CO2] using graphical vector analysis (GVA). In summary, e[CO2] significantly increased Pn and WUE by 11.9 and 29.3% under well-watered conditions, respectively, whereas the interaction of water deficit and e[CO2] slightly decreased Pn by 8.3%. Plants grown under light in an open environment were stimulated to a greater degree compared with plants grown under a lamp in a closed environment. Meanwhile, water deficit reduced Pn by 40.5 and 37.8%, while increasing WUE by 24.5 and 21.5% under ambient CO2 concentration (a[CO2]) and e[CO2], respectively. The e[CO2]-induced stimulation of WUE was attributed to the common effect of Pn and Tr, whereas a water deficit induced increase in WUE was linked to the decrease in Tr. These results suggested that water deficit lowered the stimulation of e[CO2] induced in plants. Therefore, fumigation conditions that closely mimic field conditions and multi-factorial experiments such as water availability are needed to predict the response of plants to future climate change.

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Sodium-potassium synergism inTheobroma cacao: stimulation of photosynthesis, water-use efficiency and mineral nutrition

Physiologia Plantarum ◽

10.1111/j.1399-3054.2012.01621.x ◽

2012 ◽

Vol 146 (3) ◽

pp. 350-362 ◽

Cited By ~ 43

Author(s):

James N. Gattward ◽

Alex-Alan F. Almeida ◽

José O. Souza ◽

Fábio P. Gomes ◽

Herbert J. Kronzucker

Keyword(s):

Water Use Efficiency ◽

Water Use ◽

Mineral Nutrition ◽

Sodium Potassium ◽

Use Efficiency ◽

Stimulation Of

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Simultaneous stimulation of RuBP regeneration and electron transport increases productivity and water use efficiency under field conditions

10.1101/2020.01.27.920843 ◽

2020 ◽

Author(s):

Patricia E. López-Calcagno ◽

Kenny L. Brown ◽

Andrew J. Simkin ◽

Stuart J. Fisk ◽

Tracy Lawson ◽

...

Keyword(s):

Electron Transport ◽

Water Use Efficiency ◽

Water Use ◽

Plant Biomass ◽

Carbon Assimilation ◽

Field Conditions ◽

Simultaneous Stimulation ◽

Intrinsic Water Use Efficiency ◽

Use Efficiency ◽

Stimulation Of

AbstractPrevious studies have demonstrated that independent stimulation of either electron transport or RuBP regeneration can increase the rate of photosynthetic carbon assimilation and plant biomass. In this paper, we present evidence that a multi-gene approach to simultaneously manipulate these two processes provides a further stimulation of photosynthesis. We report on the introduction of the cyanobacterial bifunctional enzyme fructose-1,6-bisphosphatase/sedoheptulose-1,7-bisphosphatase or overexpression of the plant enzyme sedoheptulose-1,7-bisphosphatase, together with expression of the red algal protein cytochrome c6, and show that a further increase in biomass accumulation under both glasshouse and field conditions can be achieved. Furthermore, we provide evidence that the simultaneous stimulation of electron transport and RuBP regeneration can lead to enhanced intrinsic water use efficiency under field conditions.One sentence summarySimultaneous stimulation of RuBP regeneration and electron transport results in improvements in biomass yield in glasshouse and field grown tobacco.

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Thirty-eight years of CO<sub>2</sub> fertilization have outpaced growing aridity to drive greening of Australian woody ecosystems

10.5194/bg-2021-218 ◽

2021 ◽

Author(s):

Sami W. Rifai ◽

Martin G. De Kauwe ◽

Anna M. Ukkola ◽

Lucas A. Cernusak ◽

Patrick Meir ◽

...

Keyword(s):

Climate Change ◽

Water Use Efficiency ◽

Water Use ◽

Heat Waves ◽

Co2 Fertilization ◽

Eastern Australia ◽

Decadal Scale ◽

Fertilization Effect ◽

Use Efficiency ◽

Co2 Fertilization Effect

Abstract. Climate change is projected to increase the imbalance between the supply (precipitation) and atmospheric demand for water (i.e. increased potential evapotranspiration), stressing plants in water-limited environments. Plants may be able to offset increasing aridity because rising CO2 increases water-use-efficiency. CO2 fertilization has also been cited as one of the drivers of the widespread ‘greening’ phenomenon. However, attributing the size of this CO2 fertilization effect is complicated, due in part to a lack of long-term vegetation monitoring and interannual to decadal-scale climate variability. In this study we asked the question, how much has CO2 contributed towards greening? We focused our analysis on a broad aridity gradient spanning eastern Australia’s woody ecosystems. Next we analysed 38-years of satellite remote sensing estimates of vegetation greenness (normalized difference vegetation index, NDVI) to examine the role of CO2 in ameliorating climate change impacts. Multiple statistical techniques were applied to separate the CO2-attributable effects on greening from the changes in water supply and atmospheric aridity. Widespread vegetation greening occurred despite a warming climate, increases in vapor pressure deficit, and repeated record-breaking droughts and heatwaves. Between 1982–2019 we found that NDVI increased (median 11.3 %) across 90.5 % of the woody regions. After masking disturbance effects (e.g. fire), we statistically estimated an 11.7 % increase in NDVI attributable to CO2, broadly consistent with a hypothesized theoretical expectation of an 8.6 % increase in water-use-efficiency due to rising CO2. In contrast to reports of a weakening CO2 fertilization effect, we found no consistent temporal change in the CO2 effect. We conclude rising CO2 has mitigated the effects of increasing aridity, repeated record-breaking droughts, and record-breaking heat waves in eastern Australia. However, we were unable to determine whether trees or grasses were the primary beneficiary of the CO2 induced change in water-use-efficiency, which has implications for projecting future ecosystem resilience. A more complete understanding of how CO2 induced changes in water-use-efficiency affect trees and non-tree vegetation is needed.

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Contrasting growth responses of Qilian juniper (Sabina przewalskii) and Qinghai spruce (Picea crassifolia) to CO2 fertilization despite common water-use efficiency increases at the northeastern Qinghai-Tibetan Plateau

Tree Physiology ◽

10.1093/treephys/tpaa169 ◽

2020 ◽

Author(s):

Wenzhi Wang ◽

Nate G McDowell ◽

Xiaohong Liu ◽

Guobao Xu ◽

Guoju Wu ◽

...

Keyword(s):

Water Use Efficiency ◽

Water Use ◽

Tree Growth ◽

Growth Responses ◽

Co2 Fertilization ◽

Picea Crassifolia ◽

Sabina Przewalskii ◽

Qilian Juniper ◽

Use Efficiency ◽

Qinghai Spruce

Abstract Rising atmospheric CO2 may enhance tree growth and mitigate drought impacts through CO2 fertilization. However, multiple studies globally have found that rising CO2 has not translated into greater tree growth despite increases in intrinsic water use efficiency (iWUE). The underlying mechanism discriminating between these two general responses to CO2 fertilization remains unclear. We used two species with contrasting stomatal regulation, the relatively anisohydric Qilian juniper (Sabina przewalskii) and relatively isohydric Qinghai spruce (Picea crassifolia), to investigate the long-term tree growth and iWUE responses to climate change and elevated CO2 using tree-ring widths and the associated cellulose stable carbon isotope ratios (δ13C). We observed a contrasting growth trend of spruce and juniper, with juniper growth increasing while spruce growth declined. The iWUE of both species increased significantly and with similar amplitude throughout the trees’ lifespan, though the relatively anisohydric juniper had higher iWUE than the relatively isohydric spruce throughout the period. Additionally, with rising CO2, the anisohydric juniper became less sensitive to drought, while the relatively isohydric spruce became more sensitive to drought. We hypothesized that rising CO2 benefits relatively anisohydric species more than relatively isohydric species due to greater opportunity to acquire carbon through photosynthesis despite warming and droughts. Our findings suggest the CO2 fertilization effect depends on the isohydric degree, which could be considered in future terrestrial ecosystem models.

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Growth, gas exchange and water use efficiency of the facultative hemiparasite Rhinanthus minor associated with hosts differing in foliar nitrogen concentration

Physiologia Plantarum ◽

10.1034/j.1399-3054.1993.890110.x ◽

1993 ◽

Vol 89 (1) ◽

pp. 64-70 ◽

Cited By ~ 13

Author(s):

W.E. Seel ◽

R.E. Cooper ◽

M.C. Press

Keyword(s):

Gas Exchange ◽

Water Use Efficiency ◽

Water Use ◽

Nitrogen Concentration ◽

Foliar Nitrogen ◽

Use Efficiency ◽

Rhinanthus Minor

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Increasing intrinsic water-use efficiency over the past 160 years does not stimulate tree growth in southeastern China

Climate Research ◽

10.3354/cr01526 ◽

2018 ◽

Vol 76 (2) ◽

pp. 115-130 ◽

Cited By ~ 5

Author(s):

G Guo ◽

K Fang ◽

J Li ◽

HW Linderholm ◽

D Li ◽

...

Keyword(s):

Water Use Efficiency ◽

Water Use ◽

Tree Growth ◽

Southeastern China ◽

The Past ◽

Intrinsic Water Use Efficiency ◽

Use Efficiency

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A comparative appraisal of urea super granule application in raised bed and prilled urea application in conventional planting for transplanted boro rice (Oryza sativa)

JOURNAL OF ADVANCES IN AGRICULTURE ◽

10.24297/jaa.v6i1.5388 ◽

2016 ◽

Vol 6 (1) ◽

pp. 822-832

Author(s):

Halim Mahmud Bhuyan ◽

Most. Razina Ferdousi ◽

Mohammad Toufiq Iqbal ◽

Ahmed Khairul Hasan

Keyword(s):

Water Use Efficiency ◽

Water Use ◽

N Fertilizer ◽

Deep Placement ◽

Prilled Urea ◽

Planting Methods ◽

Weed Infestation ◽

Use Efficiency ◽

Raised Bed ◽

Boro Rice

Utilization of urea super granule (USG) with raised bed cultivation system for transplanted boro (winter, irrigated) rice production is a major concern now days. A field experiment was conducted in the chuadanga district of Bangladesh to compare the two cultivation methods: deep placement of USG on raised bed with boro rice, and prilled urea (PU) broadcasting in conventional planting. Results showed that USG in raised bed planting increased grain yields of transplanted boro rice by up to 18.18% over PU in conventional planting. Deep placement of USG in raised bed planting increased the number of panicle m-2, number of grains panicle-1 and 1000-grains weight of boro rice than the PU in conventional planting. Better plant growth was observed by deep placement of USG in raised bed planting compared to PU in conventional planting. Sterility percentage and weed infestation were lower on USG in raised bed planting compared to the PU in conventional planting methods. Forty seven percent irrigation water and application time could be saved by USG in raised bed planting than PU in conventional planting. Deep placement of USG in bed saved N fertilizer consumption over conventional planting. Water use efficiency for grain and biomass production was higher with deep placement of USG in bed planting than the PU broadcasting in conventional planting methods. Similarly, agronomic efficiency of N fertilizer by USG in bed planting was significantly higher than the PU broadcasting in conventional planting. This study concluded that deep placement of USG in raised bed planting for transplanted boro rice is a new approach to achieve fertilizer and water use efficiency as well as higher yield and less water input compared to existing agronomic practices in Bangladesh.

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