To see the other types of publications on this topic, follow the link: Elevated air [CO2.
Journal articles on the topic 'Elevated air [CO2'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 journal articles for your research on the topic 'Elevated air [CO2.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse journal articles on a wide variety of disciplines and organise your bibliography correctly.
1
Kim, Du Hyun, and Sim Hee Han. "Direct Effects on Seed Germination of 17 Tree Species under Elevated Temperature and CO2 Conditions." Open Life Sciences 13, no. 1 (2018): 137–48. http://dx.doi.org/10.1515/biol-2018-0019.
Full textAbstract:
AbstractEffects on seed germination characteristics of 17 tree species were investigated under elevated temperature and CO2. Seeds of 5 needle-leaf and 12 broad-leaf species were germinated under four conditions: 24°C + 400 μmol CO2 mol air–1, 24°C + 750 μmol CO2 mol air–1, 27°C + 400 μmol CO2 mol air–1, and 27°C + 750 μmol CO2 mol air–1. The elevated temperature and CO2 affected germination percent (GP) of 7 tree species seeds.GPs of Pinus densiflora, P. thunbergii, Betula ermanii, and Maackia amurensisseeds were affected by the elevated temperature, while only that of P.jezoensis seed was influenced by the elevated CO2. GPs of Malus baccata and Zelkova serrataseeds were influenced by both the elevated temperature and CO2. In addition, the elevated temperature and CO2also affected mean germination time (MGT) of 12 tree species seeds. Particularly, MGTs of P. thunbergii and Rhododendron tschonoskii seeds were influenced by both factors. In conclusion, elevated temperature and CO2 affected seed germination characteristics, which were reflected by significant differences among tree species. Specifically, these two factors exerted stronger influence on germination pattern such as MGT rather than seed germination percent.
2
Lange, Diana Dostal, and Adel A. Kader. "Respiration of `Hass' Avocados in Response to Elevated CO2 Levels." HortScience 30, no. 4 (1995): 809D—809. http://dx.doi.org/10.21273/hortsci.30.4.809d.
Full textAbstract:
Stress levels of carbon dioxide can be effective in the retardation of ripening and control of decay-causing pathogens and insect infestation of some horticultural perishables. Our objective has been to identify key mitochondrial enzymes and pathways that regulate the fruit's response to CO2 actions. Oxygen uptake of fruit stored in air + 20% CO2 (16.8% O2) was depressed compared to the airstored fruit, whereas the fruit stored in air + 40% CO2 (12.6% O2) had an elevated respiration rate. Climacteric fruit treated with 20% CO2 at 10C had increased pyruvate dehydrogenase (PDH) activity, decreased cytochrome oxidase (CytOx) activity, and double the alternative oxidase (AltOx) activity compared to air-stored fruit. Air + 40% CO2-stored fruit had reduced PDH and CytOx activities, and 50% more AltOx activity than the control fruit. Mitochondria were treated directly with the same CO2-enriched atmospheres to measure the catalytic effects of CO2. Total O2 uptake was decreased in both CO2 atmospheres and the cytochrome/alternative pathway ratio was greater than with mitochondria held in air. Nuclear magnetic resonance analysis of whole fruit confirmed that these CO2 atmospheres decrease the intracellular pH several 0.1 pH units with 2 h.
3
Tobita, Komatsu, Harayama, Yazaki, Kitaoka, and Kitao. "Effects of Combined CO2 and O3 Exposures on Net CO2 Assimilation and Biomass Allocation in Seedlings of the Late-Successional Fagus Crenata." Climate 7, no. 10 (2019): 117. http://dx.doi.org/10.3390/cli7100117.
Full textAbstract:
We examined the effects of elevated CO2 and elevated O3 concentrations on net CO2 assimilation and growth of Fagus crenata in a screen-aided free-air concentration-enrichment (FACE) system. Seedlings were exposed to ambient air (control), elevated CO2 (550 µmol mol−1 CO2, +CO2), elevated O3 (double the control, +O3), and the combination of elevated CO2 and O3 (+CO2+O3) for two growing seasons. The responses in light-saturated net CO2 assimilation rates per leaf area (Agrowth-CO2) at each ambient CO2 concentration to the elevated CO2 and/or O3 treatments varied widely with leaf age. In older leaves, Agrowth-CO2 was lower in the presence of +O3 than in untreated controls, but +CO2+O3 treatment had no effect on Agrowth-CO2 compared with the +CO2 treatment. Total plant biomass increased under conditions of elevated CO2 and was largest in the +CO2+O3 treatment. Biomass allocation to roots decreased with elevated CO2 and with elevated O3. Elongation of second-flush shoots also increased in the presence of elevated CO2 and was largest in the +CO2+O3 treatment. Collectively, these results suggest that conditions of elevated CO2 and O3 contribute to enhanced plant growth; reflecting changes in biomass allocation and mitigation of the negative impacts of O3 on net CO2 assimilation.
4
Kerbel, Eduardo L., Adel A. Kader, and Roger J. Romani. "Respiratory and Glycolytic Response of Suspension-cultured `Passe Crassane' Pear Fruit Cells to Elevated CO2 Concentrations." Journal of the American Society for Horticultural Science 115, no. 1 (1990): 111–14. http://dx.doi.org/10.21273/jashs.115.1.111.
Full textAbstract:
Suspension-cultured `Passe Crassane' pear fruit (Pyrus communis L.) cells in aging media were ventilated with air or air + 20% CO2 for 4 days at 26C. Cells exposed to elevated CO2 exhibited reduced respiration (02 consumption). Ethylene production of both air and CO2-treated cells also declined to barely discernible levels by day 3. Fructose 6-phosphate (F6P) accumulated, while levels of fructose l,6-bisphosphate (F1, 6-P2), and activities of ATP and PPi phosphofructokinases (PFK and PFP) declined in response to elevated CO2. These results indicate an inhibitory effect of CO2 at the site of action of both phosphofructokinases in the glycolytic pathway, which could account, at least in part, for the observed reduction in respiration. The responses to elevated CO2 levels of the cell suspension system and intact pear fruit ventilated with air + 10% CO2 are compared, revealing a close similarity.
5
Lange, Diana L., and Adel A. Kader. "Elevated Carbon Dioxide Exposure Alters Intracellular pH and Energy Charge in Avocado Fruit Tissue." Journal of the American Society for Horticultural Science 122, no. 2 (1997): 253–57. http://dx.doi.org/10.21273/jashs.122.2.253.
Full textAbstract:
Changes in cytosolic and vacuolar pH, ATP, ADP, and the ATP : ADP ratio were measured in whole fruit or mesocarp disks of avocado [Persea americana (Mill.) cv. Hass] during brief exposures to elevated CO2. Intact climacteric fruit exposed to air (21% O2), 20% CO2 (17% O2, balance N2), or 40% CO2 (13% O2, balance N2) had cytosolic pH values of 7.0, 6.6, and 6.4, respectively, while mesocarp disks had cytosolic pH values of 6.9, 6.7, and 6.4, respectively. The ß-ATP levels of intact climacteric fruit exposed to 20% CO2 or 40% CO2 for 2 h were reduced by 25% or 43%, respectively, relative to air-exposed fruit. HPLC analysis of nucleotide phosphates from preclimacteric avocados revealed that ATP levels and the ATP : ADP ratio increased in 40% compared to the air-stored fruit. However, 1 day after transfer to air, the effects of elevated CO2 had dissipated. These modifications in cellular state could alter the activity of respiratory enzymes in fruit exposed to elevated CO2 atmospheres.
6
Bunce, James. "Crop Adaptation to Elevated CO2 and Temperature." Plants 11, no. 3 (2022): 453. http://dx.doi.org/10.3390/plants11030453.
Full text
7
Lange, Diana L., and Adel A. Kader. "Changes in Alternative Pathway and Mitochondrial Respiration in Avocado in Response to Elevated Carbon Dioxide Levels." Journal of the American Society for Horticultural Science 122, no. 2 (1997): 245–52. http://dx.doi.org/10.21273/jashs.122.2.245.
Full textAbstract:
Partially ripened avocado [Persea americana (Mill.) cv. Hass] fruit harvested in either June or Aug. 1994 were kept at 10 °C in air (21% O2), 20% CO2 (17% O2, balance N2), or 40% CO2 (13% O2, balance N2) for 7 to 12 days and then were transferred to air at 10 °C for 2 to 3 days. Mitochondrial respiration was stimulated in response to elevated CO2 treatments at 10 °C. A shift to alternative pathway (Alt) respiration occurred on day 4 in experiments using avocados from both harvest dates, with a return to initial levels in only the 20% CO2-treated fruit (June-harvested fruit after return to air). Elevated CO2 at 20 °C decreased the in vitro O2 consumption of isolated mitochondria compared to mitochondria kept in air. The Alt pathway contributed less to the total O2 uptake of CO2-treated mitochondria compared to mitochondria kept in air. The respiratory control ratios of the CO2-treated fruit and mitochondria were higher and lower, respectively, than the air controls. Induction of 33 to 37 kD proteins (corresponding to the size of the alternative oxidase proteins) occurred in avocados after 4 days in 40% CO2. These results indicate that elevated CO2 has various effects depending on concentration, duration and temperature of exposure, and mitochondrial function of avocado fruit, such as increased and altered respiratory oxidation and up-regulation of alternative oxidase proteins.
8
Pan, Qi-yuan, and Bruno Quebedeaux. "Effects of Elevated CO2 on Sorbitol Partitioning in Sink and Source Apple Leaves." HortScience 30, no. 4 (1995): 770E—770. http://dx.doi.org/10.21273/hortsci.30.4.770e.
Full textAbstract:
Apple and many other Rosaceae plants translocate sucrose as well as sorbitol. How photosynthates are partitioned between sorbitol and sucrose in the Rosaceae is not understood. This study was designed to examine the effects of elevated air CO2 on partitioning of sorbitol and other soluble sugars in sink and source apple leaves. Young `Gala' apple plants were exposed to the ambient air and 700, 1000, and 1600 μl·liter–1 of CO2 for 8 days under a light intensity of 928 μmol·m–2·s–1 with a 14-h day/10-h night cycle. Sorbitol, sucrose, glucose, and fructose concentration in sink and source leaves were determined by HPLC analysis. In source leaves, sorbitol was significantly increased, while sucrose was decreased as the air CO2 was elevated from 400 to 1600 μl·liter–1. The sorbitol/sucrose ratio varied from 1.31 in air and 2.26 at 1600 μl·liter–1 of CO2. In sink leaves, sorbitol concentration did not vary across the four CO2 levels; however, sucrose was higher at the three super-atmospheric CO2 levels. Our results suggest that increased photosynthesis via elevated CO2 favors photosynthate partitioning into sorbitol rather than sucrose. A mechanism for regulating this partitioning will be discussed.
9
Tuba, Zoltán, Michael C. F. Proctor, and Zoltán Takács. "Desiccation-Tolerant Plants under Elevated Air CO2: A Review." Zeitschrift für Naturforschung C 54, no. 9-10 (1999): 788–96. http://dx.doi.org/10.1515/znc-1999-9-1027.
Full textAbstract:
This article summarises present knowledge of the ecophysiological responses to elevated atmospheric CO2 of desiccation tolerant (DT) plants. It deals primarily with lichens and bryophytes, as the most prominent groups of DT photosynthetic organisms, but includes some comment on algae and vascular DT plants. Results of research on DT plants are compared with those on desiccation sensitive vascular C3 plants, the most widely investigated group in the field of global change. Both DT and non-DT plants show an immediate positive response of photosynthesis to elevated CO2, but in both groups the longer term effect is generally reduced (or even reversed) by down-regulation or feedback inhibition of photosynthesis, or other limitations on production and growth. In bryophytes and lichens, enhanced short-term photosynthesis may or may not be reflected in increased production; bryophytes have limited source-sink differentiation, and lichens invest excess photosynthate in secondary metabolites. DT plants may gain some advantage from elevated CO2 at both low and excessive water contents. Neither theoretical considerations nor experimental results suggest that elevated atmospheric CO2 will lead to any substantial shift in the balance of advantage between DT and non-DT plants
10
Gorny, James R., and Adel A. Kader. "Controlled-atmosphere Suppression of ACC Synthase and ACC Oxidase in `Golden Delicious' Apples during Long-term Cold Storage." Journal of the American Society for Horticultural Science 121, no. 4 (1996): 751–55. http://dx.doi.org/10.21273/jashs.121.4.751.
Full textAbstract:
Preclimacteric `Golden Delicious' apples (Malus domestica Borkh.) were stored at 0 °C in: air; air + 5% CO2; 2% O2 + 98% N2; or 2% O2 + 5% CO2 + 93% N2, and sampled monthly for 4 months to investigate the mechanism(s) by which reduced O2 and/or elevated CO2 atmospheres inhibit C2H4 biosynthesis. Ethylene biosynthesis rates and in vitro ACS activity were closely correlated in all treatments, while in vitro ACO activity significantly increased over time regardless of the treatment. Only a small amount of C2H4 biosynthesis inhibition by lowered O2 and/or elevated CO2 atmospheres could be accounted for by suppressed induction of ACO activity. Western blot analysis demonstrated that apples held for 2 months in lowered O2 and/or elevated CO2 atmospheres had significantly reduced abundance of ACO protein, compared to fruit held in air. Northern blot analysis of ACS and ACO transcript abundance revealed that reduced O2 and/or elevated CO2 atmospheres delay induction and reduce the abundance of both transcripts. Reduced O2 and/or elevated CO2 atmospheres reduce C2H4 biosynthesis by delaying and suppressing expression of ACS at the transcriptional level and by reducing the abundance of active ACO protein. Chemical names used: 1-aminocyclopropane-1-carboxylic acid (ACC), ACC synthase (ACS), ACC oxidase (ACO), ethylene (C2H4), S-adenosylmethionine (AdoMet).
11
Xu, Sheng, Jiang Yan Gao, Wei Chen, Xing Yuan He, and Yan Qing Huang. "Photosynthetic Responses of Four Urban Tree Species Exposed to Elevated CO2 and/or Elevated O3." Advanced Materials Research 641-642 (January 2013): 22–25. http://dx.doi.org/10.4028/www.scientific.net/amr.641-642.22.
Full textAbstract:
We compared the differences in photosynthesis of four urban tree species (Ginkgo biloba, Pinus tabulaeformis, Quercus mongolica and Pinus armandii) exposed to long-term elevated CO2 (700 ppm) and/or O3 (80 ppb) fumigation in (open top chamber) OTC. Our results suggest that elevated CO2 alleviated the damaging influence of elevated O3 on photosynthesis in the four urban tree species. Both Q. mongolica and P. armandii showed photosynthetic acclimation after long-term treatment under elevated CO2. The combined effect of elevated CO2 and O3 caused the changes including net photosynthetic rates (Pn), stomatal conductance (gs) and chlorophyll content that were more similar to ambient air (CK) or slightly lower than elevated CO2, indicating that elevated CO2 is able to totally or partly alleviate the harmful effects of elevated O3 on urban tree species.
12
MUNISH KAUNDAL and RAKESH KUMAR. "Effect of elevated CO2 and elevated temperature on growth and biomass accumulation in Valeriana jatamansi Jones. under different nutrient status in the western Himalaya." Journal of Agrometeorology 22, no. 4 (2021): 419–28. http://dx.doi.org/10.54386/jam.v22i4.444.
Full textAbstract:
Valeriana jatamansi is an important medicinal and aromatic plant used as sedative in modern and traditional medicines butthere is dearth of literature regarding how elevated CO2 and temperature affect on this plant. Therefore,an experiment was conducted to study the effect of elevated CO2 (550±50 µmol mol-1) and elevated temperature (2.5±0.5°C above ambient) and vermicompost on growth, phenology and biomass accumulation in V. jatamansi under Free Air CO2 Enrichment (FACE) and Free Air TemperatureIncrement (FATI) facilities at Palampur, India, during 2013-2015. Growth parameters and biomass accumulation into different parts were observed at 4, 12 and 16 months after exposure (MAE). Plant height, total dry biomass and leaf area plant -1 increased in elevated CO2 treatment applied with vermicompost as compared to the other treatments. Elevated CO2 significantly enhanced leaf area (3.5-23.5%), leaf biomass (12.7-33.2%), stem (15.3-15.6%), root (3.2-72.5%), rhizome (2.1-42.2%) and total biomass (7.7-52.7%), whereas elevated temperature increased aboveground biomass (15.0-45.3%), belowground biomass (11.6-55.5%) and total biomass (12.4-7.9%), respectively, as compared to ambient. Phenological stages were advanced by 1.2-3.9 days under FACE and FATI as compared to ambient. The results indicate that aboveground, belowground and total biomass increased under elevated CO2 and elevated temperature as compared to ambient.
13
Neufeld, Howard S. "Responses of Plants to Air Pollution and Elevated CO2." Ecology 78, no. 6 (1997): 1940–41. http://dx.doi.org/10.1890/0012-9658(1997)078[1940:roptap]2.0.co;2.
Full text
14
Lange, Diana L., and Adel A. Kader. "Effects of Elevated Carbon Dioxide on Key Mitochondrial Respiratory Enzymes in `Hass' Avocado Fruit and Fruit Disks." Journal of the American Society for Horticultural Science 122, no. 2 (1997): 238–44. http://dx.doi.org/10.21273/jashs.122.2.238.
Full textAbstract:
Preclimacteric avocado [Persea americana (Mill.) cv. Hass] fruit or fruit disks as well as fruit harvested in either June (midseason) or August (late season) and partially ripened were kept in air (21% O2 + 78% N2), 20% CO2 + 17% O2 (63% N2), or 40% CO2 + 13% O2 (47% N2) at either 10 or 20 °C. Ethylene production by preclimacteric fruit was completely inhibited during CO2 exposure, whereas there was only partial inhibition of ethylene production when partially ripened fruit were exposed. Compared to the fruit stored in air, O2 uptake of fruit stored in 20% CO2 was decreased by 20%, whereas the fruit stored in 40% CO2 showed 25% more O2 uptake than air-stored fruit. Fruit subjected to a storage regime of 40% CO2 at 10 °C followed by 2 d in air had the best visual quality. In general, climacteric fruit treated with 20% CO2 at 10 °C showed increased pyruvate dehydrogenase (PDH) activity and decreased cytochrome oxidase (CytOx) activity. Fruit stored in 40% CO2 had reduced CytOx activity compared to air-stored fruit, and PDH activity was variable depending on the harvest season of the fruit. Our results show that the effect of elevated CO2 on a given enzyme depends on concentration of CO2, duration of exposure, physiological state of the fruit, and type of tissue exposed.
15
Pelayo-Zaldívar, Clara, Jameleddine Ben Abda, Susan E. Ebeler, and Adel A. Kader. "Quality and Chemical Changes Associated with Flavor of ‘Camarosa’ Strawberries in Response to a CO2-enriched Atmosphere." HortScience 42, no. 2 (2007): 299–303. http://dx.doi.org/10.21273/hortsci.42.2.299.
Full textAbstract:
Quality and chemical changes associated with flavor were evaluated in ‘Camarosa’ strawberries (Fragaria ×ananassa) that had been kept at 5 °C in air or in air + 20 kPa CO2 for 3 and 6 days to elucidate possible factors contributing to the loss of flavor during storage. The elevated CO2 treatment did not affect flesh firmness, total soluble solids, pH, or titratable acidity. In contrast, decreases in color (as indicated by a higher hue angle value) and in concentrations of sucrose, reducing sugars, and citric acid were detected in fruits exposed to elevated CO2. Fermentative metabolites were present in strawberries stored in air and in higher concentration in those kept in air + 20 kPa CO2. Also, strawberries kept in air + 20 kPa CO2 had higher levels of ethyl esters and a major reduction in the level of methyl esters. Thus, clear differences in the aroma profile of strawberries at harvest and after 3 and 6 days of storage at 5 °C in air or air + 20 kPa CO2 were observed. This change in the volatile aroma profile is probably the primary factor contributing to the loss of strawberry flavor during storage.
16
Parmar, Rakesh, Bharati Kollah, Mayanglambam Homeshwari Devi, Sudhir Kumar Trivedi, Subhash Chandra Gupta, and Santosh Ranjan Mohanty. "Effect of Elevated CO2 and Temperature on Chlorophyll Content and Growth Attributes of Rice-wheat Cropping System in Central India." International Journal of Environment and Climate Change 14, no. 5 (2024): 375–85. http://dx.doi.org/10.9734/ijecc/2024/v14i54197.
Full textAbstract:
Rice-wheat is a major cropping system in India and it is predicted that the productivity of both crops will decline due to climate change factors including elevated CO2 and temperature. To define the mechanisms, a field experiment was carried out to evaluate the effect of elevated CO2 and temperature on growth attributes of rice and wheat crops using a Free Air CO2 Enrichment (FACE) system. The treatments were ambient CO2+ambient temperature, elevatedCO2of 600ppm+ambient temperature, ambient CO2 + elevated temperature (+2°C), ambient CO2+elevated temperature (+3°C), elevated CO2 600 ppm +elevated temperature (+2°C) and elevated CO2 600ppm +elevated temperature (+3°C). Elevated CO2 and elevated temperature (+2°C or +3°C) strongly affected the crop growth. Elevated CO2 stimulated leaf chlorophyll content, root-shoot length and biomass yield. However, elevated temperature inhibited chlorophyll content in both the crops. Elevated CO2enhanced chlorophyll content by 12.9–19% in rice and 8.8–16.5%in wheat. Elevated temperature reduced chlorophyll content by a range of 20.5-27.3% in rice and 6.3-11.5% in wheat. Combined effect of elevated CO2and elevated temperature decreased the leaf total chlorophyll and plant biomass in both crops. Study highlights that elevated CO2 concentration and rising temperature may affect the photosynthesis and productivity of rice and wheat crop in central India.
17
Kitao, Mitsutoshi, Evgenios Agathokleous, Kenichi Yazaki, Masabumi Komatsu, Satoshi Kitaoka, and Hiroyuki Tobita. "Growth and Photosynthetic Responses of Seedlings of Japanese White Birch, a Fast-Growing Pioneer Species, to Free-Air Elevated O3 and CO2." Forests 12, no. 6 (2021): 675. http://dx.doi.org/10.3390/f12060675.
Full textAbstract:
Plant growth is not solely determined by the net photosynthetic rate (A), but also influenced by the amount of leaves as a photosynthetic apparatus. To evaluate growth responses to CO2 and O3, we investigated the effects of elevated CO2 (550–560 µmol mol−1) and O3 (52 nmol mol−1; 1.7 × ambient O3) on photosynthesis and biomass allocation in seedlings of Japanese white birch (Betula platyphylla var. japonica) grown in a free-air CO2 and O3 exposure system without any limitation of root growth. Total biomass was enhanced by elevated CO2 but decreased by elevated O3. The ratio of root to shoot (R:S ratio) showed no difference among the treatment combinations, suggesting that neither elevated CO2 nor elevated O3 affected biomass allocation in the leaf. Accordingly, photosynthetic responses to CO2 and O3 might be more important for the growth response of Japanese white birch. Based on A measured under respective growth CO2 conditions, light-saturated A at a light intensity of 1500 µmol m−2 s−1 (A1500) in young leaves (ca. 30 days old) exhibited no enhancement by elevated CO2 in August, suggesting photosynthetic acclimation to elevated CO2. However, lower A1500 was observed in old leaves (ca. 60 days old) of plants grown under elevated O3 (regulated to be twice ambient O3). Conversely, light-limited A measured under a light intensity of 200 µmol m−2 s−1 (A200) was significantly enhanced by elevated CO2 in young leaves, but suppressed by elevated O3 in old leaves. Decreases in total biomass under elevated O3 might be attributed to accelerated leaf senescence by O3, indicated by the reduced A1500 and A200 in old leaves. Increases in total biomass under elevated CO2 might be attributed to enhanced A under high light intensities, which possibly occurred before the photosynthetic acclimation observed in August, and/or enhanced A under limiting light intensities.
18
Huang, Yiwen. "Direct Air Capture Technology and Its Application." Academic Journal of Science and Technology 8, no. 1 (2023): 141–44. http://dx.doi.org/10.54097/ajst.v8i1.14149.
Full textAbstract:
Direct air capture technology (DAC) is integral to achieving carbon emission targets. This paper briefly analyses the application of DAC technology in indoor CO2 removal and CO2 mineralisation. Thanks to the elevated concentration of CO2 in the air (1000ppm) and the integrated DAC unit and air conditioning unit, the indoor CO2 removal system significantly reduces energy consumption. CO2 mineralisation, combined with DAC technology, offers a safe solution for permanent carbon storage and the possibility of obtaining a valuable end product by selecting the right mineralised feedstock. Future research should continue to focus on the development of adsorbent materials and the integration of CO2 capture with subsequent applications to achieve sustainability.
19
Li, Chingying, and Adel A. Kader. "Residual Effects of Controlled Atmospheres on Postharvest Physiology and Quality of Strawberries." Journal of the American Society for Horticultural Science 114, no. 4 (1989): 629–34. http://dx.doi.org/10.21273/jashs.114.4.629.
Full textAbstract:
Abstract Low O2 (2.0%, 1.0%, or 0.5%) or elevated CO2 (10%, 15%, or 20%) concentrations and their combinations reduced respiration and ethylene production rates of ‘Selva’ strawberries (Fragaria × ananassa Duch.) stored at 2C. After transfer from the various controlled atmospheres (CA) to air, respiration and ethylene production rates increased, but were still significantly lower than those of the fruits kept continuously in air. Atmospheres of 1.0% O2 + 15% CO2 and 0.5% O2 + 20% CO2 led to the accumulation of ethanol, which was still present at concentrations >100 μl·liter−1 (ppm) in strawberry juice after their transfer to air for several days. Keeping strawberries in CA had residual effects on maintaining their flesh firmness and color, but had no significant effects on skin or juice color, titratable acidity, pH, soluble solids content, and ascorbic acid content. In general, as O2 concentration was decreased or as CO2 concentration was increased, the residual effects were more pronounced. The combinations of reduced O2 and elevated CO2 had more pronounced residual effects than either reduced O2 or elevated CO2 alone. Exposures to CA for 4 days had greater residual effects than exposure to CA for 1 to 3 days.
20
Holcroft, Deirdre M., Maria I. Gil, and Adel A. Kader. "Changes in Anthocyanin Concentration, Phenylalanine Ammonia Lyase, and Glucosyltransferase in the Arils of Pomegranates Stored in Elevated Carbon Dioxide Atmospheres." HortScience 32, no. 3 (1997): 496F—497. http://dx.doi.org/10.21273/hortsci.32.3.496f.
Full textAbstract:
The influence of CO2 on color and anthocyanin concentration in the arils of `Wonderful' pomegranate (Punica granatum L.) was investigated. Pomegranates were placed in jars ventilated continuously with air or air enriched with 10% or 20% CO2 at 10°C for 6 weeks. Samples were taken initially, and after 1, 2, 4, and 6 weeks and anthocyanin concentration was measured by HPLC. The arils of the pomegranates stored in air were deeper red than those stored in CO2-enriched atmospheres. This increase in red color resulted from an increase in anthocyanin concentration. Arils from fruit stored in air+10% CO2 had a lower anthocyanin concentration than air-stored fruit, and atmospheres enriched with 20% CO2 suppressed anthocyanin biosynthesis. Anthocyanin concentration was well-correlated to the activity of phenylalanine ammonia lyase (PAL), but not to glucosyltransferase (GT) activity. Moderate CO2 atmospheres (10%) prolong the storage life and maintain the quality of pomegranates, including an adequate red color of the arils.
21
Wu, Jingjing, Herbert J. Kronzucker, and Weiming Shi. "Dynamic analysis of the impact of free-air CO2 enrichment (FACE) on biomass and N uptake in two contrasting genotypes of rice." Functional Plant Biology 45, no. 7 (2018): 696. http://dx.doi.org/10.1071/fp17278.
Full textAbstract:
Elevated CO2 concentrations ([CO2]) in the atmosphere often increase photosynthetic rates and crop yields. However, the degree of the CO2 enhancement varies substantially among cultivars and with growth stage. Here, we examined the responses of two rice cultivars, Wuyunjing23 (WYJ) and IIyou084 (IIY), to two [CO2] (~400 vs ~600) and two nitrogen (N) provision conditions at five growth stages. In general, both seed yield and aboveground biomass were more responsive to elevated [CO2] in IIY than WYJ. However, the responses significantly changed at different N levels and growth stages. At the low N input, yield response to elevated [CO2] was negligible in both cultivars while, at the normal input, yield in IIY was 18.8% higher under elevated [CO2] than ambient [CO2]. Also, responses to elevated [CO2] significantly differed among various growth stages. Elevated [CO2] tended to increase aboveground plant biomass in both cultivars at the panicle initiation (PI) and the heading stages, but this effect was significant only in IIY by the mid-ripening and the grain maturity stages. In contrast, CO2 enhancement of root biomass only occurred in IIY. Elevated [CO2] increased both total N uptake and seed N in IIY but only increased seed N in WYJ, indicating that it enhanced N translocation to seeds in both cultivars but promoted plant N acquisition only in IIY. Root C accumulation and N uptake also exhibited stronger responses in IIY than in WYJ, particularly at the heading stage, which may play a pivotal role in seed filling and seed yield. Our results showed that the more effective use of CO2 in IIY compared with WYJ results in a strong response in root growth, nitrogen uptake, and in yield. These findings suggest that selection of [CO2]-responsive rice cultivars may help optimise the rice yield under future [CO2] scenarios.
22
Bunce, James. "Carboxylation Capacity Can Limit C3 Photosynthesis at Elevated CO2 throughout Diurnal Cycles." Plants 10, no. 12 (2021): 2603. http://dx.doi.org/10.3390/plants10122603.
Full textAbstract:
The response of carbon fixation in C3 plants to elevated CO2 is relatively larger when photosynthesis is limited by carboxylation capacity (VC) than when limited by electron transport (J). Recent experiments under controlled, steady-state conditions have shown that photosynthesis at elevated CO2 may be limited by VC even at limiting PPFD. These experiments were designed to test whether this also occurs in dynamic field environments. Leaf gas exchange was recorded every 5 min using two identical instruments both attached to the same leaf. The CO2 concentration in one instrument was controlled at 400 μmol mol−1 and one at 600 μmol mol−1. Leaves were exposed to ambient sunlight outdoors, and cuvette air temperatures tracked ambient outside air temperature. The water content of air in the leaf cuvettes was kept close to that of the ambient air. These measurements were conducted on multiple, mostly clear days for each of three species, Glycine max, Lablab purpureus, and Hemerocallis fulva. The results indicated that in all species, photosynthesis was limited by VC rather than J at both ambient and elevated CO2 both at high midday PPFDs and also at limiting PPFDs in the early morning and late afternoon. During brief reductions in PPFD due to midday clouds, photosynthesis became limited by J. The net result of the apparent deactivation of Rubisco at low PPFD was that the relative stimulation of diurnal carbon fixation at elevated CO2 was larger than would be predicted when assuming limitation of photosynthesis by J at low PPFD.
23
Blobner, Manfred, Ralph Bogdanski, Eberhard Kochs, Julia Henke, Alexander Findeis, and Sabine Jelen-Esselborn. "Effects of Intraabdominanlly Insufflated Carbon Dioxide and Elevated Intraabdominal Pressure on Splanchnic Circulation." Anesthesiology 89, no. 2 (1998): 475–82. http://dx.doi.org/10.1097/00000542-199808000-00025.
Full textAbstract:
Background Intraabdominally insufflated carbon dioxide (CO2) during laparoscopy may have a specific effect on splanchnic circulation that may be unrelated to the effects of increased intraabdominal pressure alone. Therefore, the influences of insufflation with CO2 versus air on splanchnic circulation were compared. Methods Pigs were chronically instrumented for continuous recording of mesenteric artery, portal venous, inferior vena cava, and pulmonary arterial blood flow and portal venous pressure. After induction of anesthesia, CO2 or air was insufflated in 14 and 10 pigs, respectively. With the pigs in the supine position, intraabdominal pressure was increased in steps of 4 mmHg up to 24 mmHg by graded gas insufflation. Results During air insufflation, mesenteric artery vascular resistance was unchanged, whereas mesenteric arterial blood flow decreased with increasing intraabdominal pressure. Shortly after CO2 insufflation to an intraabdominal pressure of 4 mmHg, mean arterial pressure, mesenteric arterial blood flow, and mesenteric arterial vascular resistance were increased by 21%, 12% and 9%, respectively. Subsequently, with the onset of CO2 resorption in the third minute, mean arterial pressure declined to baseline values and mesenteric arterial vascular resistance declined to 85% of baseline values, whereas mesenteric arterial blood flow continued to increase to a maximum of 24% higher than baseline values. At steady-state conditions during CO2 insufflation, mesenteric arterial blood flow was increased up to an intraabdominal pressure 16 mmHg but decreased at higher intraabdominal pressures. Conclusions In contrast to air insufflation, intraabdominal insufflation of CO2 resulted in a moderate splanchnic hyperemia at an intraabdominal pressure < or = 12 mmHg. At higher intraabdominal pressure values, pressure-induced changes became more important than the type of gas used.
24
Lange, Diana Dostal, and Adel A. Kader. "373 MITOCHONDRIAL RESPIRATlON OF `HASS' AVOCADOS IN RESPONSE TO ELEVATED CO, CONCENTRATIONS." HortScience 29, no. 5 (1994): 484e—484. http://dx.doi.org/10.21273/hortsci.29.5.484e.
Full textAbstract:
Carbon dioxide-enriched atmospheres can be effective in the retardation of ripening and in the reduction of decay of horticultural commodities. However, concentrations in excess of the tolerance level may cause physiological damage. The goal of our research is to elucidate the specific regulatory mechanisms of CO2 actions. Cytochrome oxidase (CytOx) in vitro activity in preclimacteric avocado fruit stored in air or 40% CO2 + 12.6% O2 was evaluated at 20C. Activities were determined during treatment and also after a transfer to air. Fruit treated with 40% CO2 + 12.6% O2 had elevated CytOx in vitro activity when compared to air-stored fruit. Immunoblot analysis was performed to determine if the increase in CytOx activity could be due to an increase in enzyme concentration. The decline in respiration rate of CO,-treated fruit was most likely due to the decrease in intracellular pH and its effect on the activities of important respiratory enzymes, including CytOx. The regulatory mechanisms of other mitochondrial respiratory enzymes in `Hass' avocados exposed to elevated CO2 atmospheres are also under investigation.
25
Bender, R. J., and J. K. Brecht. "Elevated CO2 Atmosphere for Storage of Mature-green and Tree-ripe `Tommy Atkins' Mangoes." HortScience 30, no. 4 (1995): 804F—805. http://dx.doi.org/10.21273/hortsci.30.4.804f.
Full textAbstract:
Mangoes for long-distance markets are harvested at the mature-green stage and shipped in refrigerated containers. Shipment under controlled atmosphere is still tentative, and the CO2 concentrations used are relatively low (maximum 10%), although mangoes have been reported as being less-sensitive to elevated CO2 than other tropical fruits. In the present study, CO2 concentrations of 10%, 15%, 25%, 35%, and 45% combined with 5% O2 were used to store mangoes. Mature-green `Tommy Atkins' were stored for 21 days at 12C, followed by air storage at 20C for 5 days. Tree-ripe mangoes were stored at 8 or 12C under the same conditions. Ethanol production rates increased along with increasing CO2 concentrations. However, only 35% and 45% CO2 atmospheres inflicted damage. Color development was severely inhibited under those treatments. Lower CO2 treatments, up to 25% in the storage atmosphere, inhibited skin color development and ethylene biosynthesis but, after 5 days in air at 20C, skin color and ethylene production reached control levels. Fruit flesh firmness did not differ among treatments at 12C. Tree ripe mangoes stored in CA at 8C were only significantly firmer than control fruit at transfer from CA to air.
26
Bender, R. J., and J. K. Brecht. "Elevated CO2 Atmosphere for Storage of Mature-green and Tree-ripe `Tommy Atkins' Mangoes." HortScience 30, no. 4 (1995): 804F—805. http://dx.doi.org/10.21273/hortsci.30.4.804.
Full textAbstract:
Mangoes for long-distance markets are harvested at the mature-green stage and shipped in refrigerated containers. Shipment under controlled atmosphere is still tentative, and the CO2 concentrations used are relatively low (maximum 10%), although mangoes have been reported as being less-sensitive to elevated CO2 than other tropical fruits. In the present study, CO2 concentrations of 10%, 15%, 25%, 35%, and 45% combined with 5% O2 were used to store mangoes. Mature-green `Tommy Atkins' were stored for 21 days at 12C, followed by air storage at 20C for 5 days. Tree-ripe mangoes were stored at 8 or 12C under the same conditions. Ethanol production rates increased along with increasing CO2 concentrations. However, only 35% and 45% CO2 atmospheres inflicted damage. Color development was severely inhibited under those treatments. Lower CO2 treatments, up to 25% in the storage atmosphere, inhibited skin color development and ethylene biosynthesis but, after 5 days in air at 20C, skin color and ethylene production reached control levels. Fruit flesh firmness did not differ among treatments at 12C. Tree ripe mangoes stored in CA at 8C were only significantly firmer than control fruit at transfer from CA to air.
27
Adireddy, Rajanna G., Saseendran S. Anapalli, Krishna N. Reddy, Partson Mubvumba, and Justin George. "Possible Impacts of Elevated CO2 and Temperature on Growth and Development of Grain Legumes." Environments 11, no. 12 (2024): 273. https://doi.org/10.3390/environments11120273.
Full textAbstract:
Carbon dioxide (CO2) is the most abundant greenhouse gas (GHG) in the atmosphere and the substrate for the photosynthetic fixation of carbohydrates in plants. Increasing GHGs from anthropogenic emissions is warming the Earth’s atmospheric system at an alarming rate and changing its climate, which can affect photosynthesis and other biochemical reactions in crop plants favorably or unfavorably, depending on plant species. For the substrate role in plant carbon reduction reactions, CO2 concentration ([CO2]) in air potentially enhances photosynthesis. However, N uptake and availability for protein synthesis can be a potential limiting factor in enhanced biomass synthesis under enriched [CO2] conditions across species. Legumes are C3 plants and symbiotic N fixers and are expected to benefit from enhanced [CO2] in the air. However, the concurrent increase in air temperatures with enhanced [CO2] demands more detailed investigations on the effects of [CO2] enhancement on grain legume growth and yield. In this article, we critically reviewed and presented the online literature on growth, phenology, photosynthetic rate, stomatal conductance, productivity, soil health, and insect behavior under elevated [CO2] and temperature conditions. The review revealed that specific leaf weight, pod weight, and nodule number and weight increased significantly under elevated [CO2] of up to 750 ppm. Under elevated [CO2], two mechanisms that were affected were the photosynthesis rate (increased) and stomatal conductivity (decreased), which helped enhance water use efficiency in the C3 legume plants to achieve higher yields. Exposure of legumes to elevated levels of [CO2] when water stressed resulted in an increase of 58% in [CO2] uptake, 73% in transpiration efficiency, and 41% in rubisco carboxylation and decreased stomatal conductance by 15–30%. The elevated [CO2] enhanced the yields of soybean by 10–101%, peanut by 28–39%, mung bean by 20–28%, chickpea by 26–31%, and pigeon pea by 31–38% over ambient [CO2]. However, seed nutritional qualities like protein, Zn, and Ca were significantly decreased. Increased soil temperatures stimulate microbial activity, spiking organic matter decomposition rates and nutrient release into the soil system. Elevated temperatures impact insect behavior through higher plant feeding rates, posing an enhanced risk of invasive pest attacks in legumes. However, further investigations on the potential interaction effects of elevated [CO2] and temperatures and extreme climate events on growth, seed yields and nutritional qualities, soil health, and insect behavior are required to develop climate-resilient management practices through the development of novel genotypes, irrigation technologies, and fertilizer management for sustainable legume production systems.
28
Hakala, Kaija, Timo Mela, Heikki Laurila, and Timo Kaukoranta. "Arrangement of experiments for simulating the effects of elevated temperatures and elevated CO2 levels on field-sown crops in Finland." Agricultural and Food Science 5, no. 1 (1996): 25–47. http://dx.doi.org/10.23986/afsci.72728.
Full textAbstract:
The experimental plants: spring wheat, winterwheat, spring barley, meadow fescue, potato, strawberry and black currant were sown or planted directly in the field, part of which was covered by an automatically controlled greenhouse to elevate the temperature by 3°C. The temperature of the other part of the field (open field) was not elevated, but the field was covered with the same plastic film as the greenhouse to achieve radiation and rainfall conditions comparable to those in the greenhouse. To elevate the CO2 concentrations, four open top chambers (OTC) were built for the greenhouse, and four for the open field. Two of these, both in the greenhouse and in the open field, were supplied with pure CO2 to elevate their CO2 level to 700 ppm. The temperatures inside the greenhouse followed accurately the desired level. The relative humidity was somewhat higher in the greenhouse and in the OTC:s than in the open field, especially after the modifications in the ventilation of the greenhouse and in the OTC:s in 1994. Because the OTC:s were large (3 m in diameter), the temperatures inside them differed very little from the surrounding air temperature. The short-term variation in the CO2 concentrations in the OTC:s with elevated CO2 was, however, quite high. The control of the CO2 concentrations improved each year from 1992 to 1994, as the CO2 supplying system was modified. The effects of the experimental conditions on plant growth and phenology are discussed.
29
Hasegawa, Toshihiro, Hidemitsu Sakai, Takeshi Tokida, et al. "Rice cultivar responses to elevated CO2 at two free-air CO2 enrichment (FACE) sites in Japan." Functional Plant Biology 40, no. 2 (2013): 148. http://dx.doi.org/10.1071/fp12357.
Full textAbstract:
There is some evidence that rice cultivars respond differently to elevated CO2 concentrations ([CO2]), but [CO2] × cultivar interaction has never been tested under open-field conditions across different sites. Here, we report on trials conducted at free-air CO2 enrichment (FACE) facilities at two sites in Japan, Shizukuishi (2007 and 2008) and Tsukuba (2010). The average growing-season air temperature was more than 5°C warmer at Tsukuba than at Shizukuishi. For four cultivars tested at both sites, the [CO2] × cultivar interaction was significant for brown rice yield, but there was no significant interaction with site-year. Higher-yielding cultivars with a large sink size showed a greater [CO2] response. The Tsukuba FACE experiment, which included eight cultivars, revealed a wider range of yield enhancement (3–36%) than the multi-site experiment. All of the tested yield components contributed to this enhancement, but there was a highly significant [CO2] × cultivar interaction for percentage of ripened spikelets. These results suggest that a large sink is a prerequisite for higher productivity under elevated [CO2], but that improving carbon allocation by increasing grain setting may also be a practical way of increasing the yield response to elevated [CO2].
30
Holtum, J. A. M., and K. Winter. "Are plants growing close to the floors of tropical forests exposed to markedly elevated concentrations of carbon dioxide?" Australian Journal of Botany 49, no. 5 (2001): 629. http://dx.doi.org/10.1071/bt00054.
Full textAbstract:
The study tested the frequently expressed perception that the concentration of CO2 in the vicinity of establishing seedlings growing close to tropical forest floors is generally high. CO2 concentration was monitored 10 cm from the forest floor over several days during wet and dry seasons at three Panamanian lowland and montane tropical forest sites. Air was sampled at a low flow rate with a peristaltic pump to minimise contamination by air from other strata. The average CO2 concentrations observed during the dry and wet seasons were 387 and 423 L CO2 L–1 air, respectively, a relatively small enrichment compared with the above-canopy CO2 concentrations. The highest CO2 concentration recorded at 10 cm was 494 L L–1. The generally modest levels of enrichment—far below concentrations required to saturate photosynthesis—were nonetheless sufficient to significantly increase the rates of CO2 uptake relative to above-canopy CO2 concentrations by shade-grown seedlings of Piper cordulatum C. DC., an understorey shrub and Virola surinamensis(Rol.) Warb., a late successional tree species.
31
Parmar, Rakesh, Subhash Chandra Gupta, Bharati Kollah, et al. "Influence of Elevated CO2 and Temperature on Yield Attributes of Rice and Wheat in Central India." Journal of Experimental Agriculture International 46, no. 7 (2024): 374–95. http://dx.doi.org/10.9734/jeai/2024/v46i72592.
Full textAbstract:
Elevated CO2 and rising temperature are the major climate changing drivers to attain sustainability in agriculture. The current experiment was carried out to evaluate the extent of impact of climate changing factors on rice and wheat crop. Field experiment was carried out under a Free Air CO2 Enrichment (FACE) condition. The treatments consisted of ambient CO2 and temperature, elevated CO2 of 600ppm + ambient temperature, ambient CO2 + elevated temperature (+2°C), ambient CO2+elevated temperature (+3°C), elevated CO2 of 600 ppm + elevated temperature (+2°C) and elevated CO2 600ppm + elevated temperature (+3°C). The plant yield attributes were biomass, tillers per plant, productive tillers per plant, failure tillers per plant, total number of grains per panicle, failure grains per panicle and test weight. Elevated CO2 stimulated biomass and other yield attributes in both crops. However, elevated temperature inhibited yield attributes. Elevated CO2 enhanced biomass but elevated temperature reduced biomass of crops. Elevated CO2 influenced tillers per plant in rice by -26.9% to 16.6% and in wheat by 3.7% to 25.9%. Elevated temperature affected number tillers up to 26.9%. Number of productive tillers in rice ranged from -28.5% to 21.4% and in wheat by -29.1% to 36%. In wheat the number of grains per panicle varied from -24.3% to 6%. Test weight of grains varied from -9.1% to 4.6% in rice. Combined effect of elevated CO2 and elevated temperature had differential effect on crops. Study highlights that yield attributes and productivity of rice and wheat crop will be affected under elevated CO2 and rising temperature in central part of India and warrants necessary interventions to alleviate climate stress.
32
Ponzoni, Flávio Jorge, Emilia Hamada, Renata Ribeiro do Valle Gonçalves, and Ricardo Antônio Almeida Pazianotto. "Effect of elevated atmospheric CO2 on spectral reflectance of coffee leaves of plants cultivated at face facility." Labor e Engenho 17 (December 29, 2023): e023023. http://dx.doi.org/10.20396/labore.v17i00.8674473.
Full textAbstract:
Climate change impacts are stressing many economic sectors worldwide, including agriculture, increasingly hindering efforts to meet human needs. Dioxide carbon is one of the main greenhouse gases and it affects directly the crop production. The objective of this study was to evaluate if established remote sensing indices could detect the effects of elevated atmospheric CO2 on the leaves of coffee (Coffea arabica L.) plantation growing under field conditions. Plots of coffee plants were exposed to ambient air (~390 µmol CO2 mol-1) and elevated CO2 (~550 µmol CO2 mol-1) at the free air CO2 enrichment (FACE) experiment. The statistical design was the completely randomized blocks with six replicates per treatment (ambient CO2 and elevated CO2), with 10m-diameter plots. Coffee leaves were spectrally characterized by reflectance spectra on their adaxial surfaces and seven vegetation indices were calculated from reflectance data: chlorophyll normalized difference index (Chl NDI), normalized difference nitrogen index (NDNI), normalized difference vegetation index (NDVI), photochemical reflectance index (PRI), pigment specific simple ration indices for chlorophyll a (PSSRa) and chlorophyll b (PSSRb), and structural independent pigment index (SIPI). NDNI was a sensitive indicator of the atmospheric CO2 effects on coffee leaves. NDVI, PSSRa and PSSRb were sensitive to estimate the effect of elevated CO2 only under drought conditions. These indices identify the effect of CO2 when a long period with high precipitation deficit stressing the leaves occurred. Chl NDI, PRI and SIPI were not sensitive to atmospheric CO2.
33
Skog, L. J., R. B. Smith, and D. P. Murr. "The Effect of Delayed Cold Storage and Controlled-atmosphere Storage on Chilling Injury in Nectarines." HortScience 30, no. 4 (1995): 815D—815. http://dx.doi.org/10.21273/hortsci.30.4.815d.
Full textAbstract:
`Fantasia' nectarines (Prunus persica L.Batsch) were either stored immediately at 0.5C or subjected to a 48-h delay at 20C in air or with 5% CO2 in air before storage. Samples were evaluated at harvest and after 18, 25, 32, 39 and 46 days storage in air or in 5% O2 with 0%, 4%, 8%, or 12% CO2. All samples were evaluated at optimum ripeness. A combination of delayed storage and elevated CO2 in storage effectively delayed chilling injury (CI) symptoms. Control of CI increased with increasing CO2 level in delayed and nondelayed treatments. Delayed storage was not effective without elevated levels of CO2 in the storage atmosphere. Fruit that was stored without delay did not soften normally during the ripening period and developed a dry, rubbery texture. The effect was enhanced as CI progressed, resulting in increased firmness of ripened fruit with increased storage time. The delayed storage treatments softened normally during ripening, but CI fruit had a dry, mealy texture. Internal conductivity measurements correlated well with CI development. Off-flavors were detected at the higher levels of CO2 storage.
34
Zhu, Jun, Duane P. Bartholomew, and Guillermo Goldstein. "Effect of Elevated Carbon Dioxide on the Growth and Physiological Responses of Pineapple, A Species with Crassulacean Acid Metabolism." Journal of the American Society for Horticultural Science 122, no. 2 (1997): 233–37. http://dx.doi.org/10.21273/jashs.122.2.233.
Full textAbstract:
Despite the potential impact of rising global CO2 levels, only a limited number of studies have been conducted on the effects of ambient and elevated CO2 on plants having Crassulacean acid metabolism (CAM). To our knowledge, there are no studies for pineapple [Ananas comosus (L.) Merr.], the most commercially important CAM plant. Pineapple plants were grown at CO2 levels of ≈330 (ambient) and ≈730 (elevated) μmol·mol-1 in open-top chambers for 4 months. The mean air temperature in the chambers was ≈39 °C day/24 °C night. Average plant dry mass at harvest was 180 g per plant at elevated CO2 and 146 g per plant at ambient CO2. More biomass was partitioned to stem and root but less to leaf for plants grown at elevated CO2; leaf thickness was 11% greater at elevated than at ambient CO2. The diurnal difference in leaf titratable acidity (H+) at elevated CO2 reached 347 mmol·m-2, which was up to 42% greater than levels in plants grown in ambient CO2. Carbon isotopic discrimination (Δ) of plants was 3.75% at ambient CO2 and 3.17% at elevated CO2, indicating that CO2 uptake via the CAM pathway was enhanced more by elevated CO2 than uptake via the C3 pathway. The nonphotochemical quenching coefficient (qN) of leaves was ≈45% lower in the early morning for plants grown at elevated than at ambient CO2, while afternoon values were comparable. The qN data suggested that the fixation of external CO2 was enhanced by elevated CO2 in the morning but not in the afternoon when leaf temperature was ≥40 °C. We found no effect of CO2 levels on leaf N or chlorophyll content. Pineapple dry matter gain was enhanced by elevated CO2, mainly due to increased CO2 dark fixation in environments with day temperatures high enough to suppress C3 photosynthesis.
35
Thilakarathne, Chamindathee L., Sabine Tausz-Posch, Karen Cane, et al. "Intraspecific variation in leaf growth of wheat (Triticum aestivum) under Australian Grain Free Air CO2 Enrichment (AGFACE): is it regulated through carbon and/or nitrogen supply?" Functional Plant Biology 42, no. 3 (2015): 299. http://dx.doi.org/10.1071/fp14125.
Full textAbstract:
Underlying physiological mechanisms of intraspecific variation in growth response to elevated CO2 concentration [CO2] were investigated using two spring wheat (Triticum aestivum L.) cultivars: Yitpi and H45. Leaf blade elongation rate (LER), leaf carbon (C), nitrogen (N) in the expanding leaf blade (ELB, sink) and photosynthesis (A) and C and N status in the last fully expanded leaf blade (LFELB, source) were measured. Plants were grown at ambient [CO2] (~384µmolmol–1) and elevated [CO2] (~550µmolmol–1) in the Australian Grains Free Air CO2 Enrichment facility. Elevated [CO2] increased leaf area and total dry mass production, respectively, by 42 and 53% for Yitpi compared with 2 and 13% for H45. Elevated [CO2] also stimulated the LER by 36% for Yitpi compared with 5% for H45. Yitpi showed a 99% increase in A at elevated [CO2] but no A stimulation was found for H45. There was a strong correlation (r2=0.807) between LER of the ELB and soluble carbohydrate concentration in LFELB. In ELB, the highest spatial N concentration was observed in the cell division zone, where N concentrations were 67.3 and 60.6mg g–1 for Yitpi compared with 51.1 and 39.2mg g–1 for H45 at ambient and elevated [CO2]. In contrast, C concentration increased only in the cell division and cell expansion zone of the ELB of Yitpi. These findings suggest that C supply from the source (LFELB) is cultivar dependent and well correlated with LER, leaf area expansion and whole-plant growth response to elevated [CO2].
36
Kobayashi, T., K. Ishiguro, T. Nakajima, H. Y. Kim, M. Okada, and K. Kobayashi. "Effects of Elevated Atmospheric CO2 Concentration on the Infection of Rice Blast and Sheath Blight." Phytopathology® 96, no. 4 (2006): 425–31. http://dx.doi.org/10.1094/phyto-96-0425.
Full textAbstract:
The effect of elevated atmospheric CO2 concentration on rice blast and sheath blight disease severity was studied in the field in northern Japan for 3 years. With free-air CO2 enrichment (FACE), rice plants were grown in ambient and elevated (≈200 to 280 μmol mol-1 above ambient) CO2 concentrations, and were artificially inoculated with consist of Magnaporthe oryzae. Rice plants grown in an elevated CO2 concentration were more susceptible to leaf blast than those in ambient CO2 as indicated by the increased number of leaf blast lesions. Plants grown under elevated CO2 concentration had lower leaf silicon content, which may have contributed to the increased susceptibility to leaf blast under elevated CO2 concentrations. In contrast to leaf blast, panicle blast severity was unchanged by the CO2 enrichment under artificial inoculation, whereas it was slightly but significantly higher under elevated CO2 concentrations in a spontaneous rice blast epidemic. For naturally occurring epidemics of the sheath blight development in rice plants, the percentage of diseased plants was higher under elevated as opposed to ambient CO2 concentrations. However, the average height of lesions above the soil surface was similar between the treatments. One hypothesis is that the higher number of tillers observed under elevated CO2 concentrations may have increased the chance for fungal sclerotia to adhere to the leaf sheath at the water surface. Consequently, the potential risks for infection of leaf blast and epidemics of sheath blight would increase in rice grown under elevated CO2 concentration.
37
Novello, Nicola, Mani Naiker, Haydee Laza, Kerry B. Walsh, and Sabine Tausz-Posch. "Design of a Low-Cost Open-Top Chamber Facility for the Investigation of the Effects of Elevated Carbon Dioxide Levels on Plant Growth." Hardware 2, no. 2 (2024): 138–53. http://dx.doi.org/10.3390/hardware2020007.
Full textAbstract:
Open-top chambers (OTCs) consist of semi-open enclosures used to investigate the impact of elevated carbon dioxide [CO2] on crops and larger plant communities. OTCs have lower operational costs than alternatives such as controlled environment cabinets and Free Air Carbon Dioxide Enrichment (FACE). A low-cost design is presented for an OTC with a surface area of 1.2 m2 and a target elevated CO2 concentration [CO2] of 650 µmol mol−1 adequate for trials involving cereals or grain legumes. The elevated CO2 chambers maintained an average concentration ± standard deviation of 652 ± 37 µmol mol−1 despite wind and air turbulences, in comparison to 407 ± 10 µmol mol−1 for non-enriched chambers. Relative to ambient (non-chamber) conditions, plants in the chambers were exposed to slightly warmer conditions (2.3 °C in daylight hours; 0.6 °C during night environment). The materials’ cost for constructing the chambers was USD 560 per chamber, while the CO2 control system for four chambers dedicated to CO2-enriched conditions cost USD 5388. To maintain the concentration of 650 µmol mol−1 during daylight hours, each chamber consumed 1.38 L min−1 of CO2. This means that a size G CO2 cylinder was consumed in 8–9 days in the operation of two chambers (at USD 40).
38
SUMIT KUMAR DEY, B. CHAKRABARTI, R. PRASANNA, R. MITTAL, S. D. SINGH, and H. PATHAK. "Growth and biomass partitioning in mungbean with elevated carbon dioxide, phosphorus levels and cyanobacteria inoculation." Journal of Agrometeorology 18, no. 1 (2016): 7–12. http://dx.doi.org/10.54386/jam.v18i1.841.
Full textAbstract:
Mungbean is an important leguminous crop providing protein for the rural and urban poor in South and Southeast Asia. An experiment was conducted in free air carbon dioxide enrichment facility (FACE) ring to study the impact of increased CO2 level on growth and biomass partitioning in mungbean crop. The crop was grown under ambient (400 μmol mol-1) and elevated CO2 concentration (550 μmol mol-1) with 5 doses of P with and without cyanobacterial inoculation. Elevated CO2 significantly increased biomass accumulation in mungbean crop which was further increased by P and cyanobacteria application. Leaf biomass increased by 34.4% at increased CO2 level. Maximum biomass allocation to seeds was observed with P dose of 16 mg kg-1 soil in both ambient and elevated CO2 conditions. Allocation was more in high CO2 treatment. The study concludes that mungbean crop grown under elevated CO2 condition accumulates more biomass which gets further improved by application of P nutrient and cyanobacteria inoculation.
39
Zhang, Jianzhi Jenny, and Christopher B. Watkins. "Fruit Quality, Fermentation Products, and Activities of Associated Enzymes During Elevated CO2 Treatment of Strawberry Fruit at High and Low Temperatures." Journal of the American Society for Horticultural Science 130, no. 1 (2005): 124–30. http://dx.doi.org/10.21273/jashs.130.1.124.
Full textAbstract:
The effects of postharvest treatments of air and 20 kPa CO2 (in air) at 2 or 20 °C on color, firmness, accumulations of acetaldehyde, ethanol, and ethyl acetate, activities of pyruvate decarboxylase (PDC) and alcohol dehydrogenase (ADH) activity, and expression of an ADH gene were studied in strawberry fruit (Fragaria ×ananassa Duch. cv. Jewel). CO2 treatment enhanced strawberry fruit firmness at 2 °C but not 20 °C, while the rate of color changes was affected by CO2 treatment at 20 °C but not at 2 °C. Temperature also affected the accumulation of acetaldehyde, ethanol and ethyl acetate in CO2-treated fruit. All three compounds accumulated in fruits at 2 °C. At 20 °C, ethanol accumulated slightly by day 6, although ethyl acetate accumulated in fruit from both atmospheres. PDC enzyme activity was higher in CO2-treated fruit than their air-treated control at 2 °C but not at 20 °C. ADH activity and ADH mRNA accumulation of the CO2-treated berries were higher than in air at 20 °C but not 2 °C. The results, overall, indicate that patterns of change among gene expression, enzyme activities, and fermentation product accumulation were not consistent.
40
Vannak, Heak, Yugo Osaka, Takuya Tsujiguchi, and Akio Kodama. "Air-Purge Regenerative Direct Air Capture Using an Externally Heated and Cooled Temperature-Swing Adsorber Packed with Solid Amine." Separations 10, no. 7 (2023): 415. http://dx.doi.org/10.3390/separations10070415.
Full textAbstract:
CO2 capture from air is crucial in achieving negative emissions. Based on conventional or newly developed high-enriching processes, we investigated the rough enrichment of CO2 from air via an externally heated or cooled adsorber (temperature-swing adsorption, TSA), along with air purge using double-pipe heat exchangers packed with low-volatility polyamine-loaded silica. A simple adsorption–desorption cycle was attempted in a TSA experiment, by varying the temperature from 20 °C to 60 °C using moist air, yielding an average CO2 concentration of product gas that was ~17 times higher than the feed air, but the CO2 recovery rate was poor. A double-step adsorption process was applied to increase CO2 adsorption and recovery simultaneously. In this process, substantial-CO2-concentration gas was used as the product gas, and the remaining gas was used as the reflux feed gas for adsorber. This method can provide a product gas with ~100 times higher CO2 concentration than raw gas, with a recovery ratio ~60% under the shortest adsorption/desorption time and the longest refluxing time of cycle operation. Therefore, the refluxing step significantly helped to enhance CO2 capture via adsorption from elevated-CO2-concentration recirculating gas. With this CO2 concentration, the product gas can serve as the CO2 supplement for the growing plant processes.
41
Siriphanich, Jingtair, and Adel A. Kader. "Changes in Cytoplasmic and Vacuolar pH in Harvested Lettuce Tissue as Influenced by CO2." Journal of the American Society for Horticultural Science 111, no. 1 (1986): 73–77. http://dx.doi.org/10.21273/jashs.111.1.73.
Full textAbstract:
Abstract ‘Climax’ lettuce (Lactuca sativa L.) exhibited more severe CO2 injury symptoms than ‘Salinas’ and ‘Winterhaven’ lettuce when exposed at 20°C to air for 1 day following treatment for 6 days at 0° with 15% CO2 in air. All 3 cultivars, however, had similar decreases as revealed by NMR analysis, of about 0.4 and 0.1 pH units in the cytoplasm and vacuole, respectively. This result indicates that variation in the buffering capacity was not related to differences in susceptibility to CO2 injury among these cultivars. Although CO2 reduced pH, it also reduced titratable acidity of lettuce tissue. This change resulted in a higher pH when the lettuce was moved to air. Exposure of lettuce at 0° to light reduced CO2 injury by about 50% relative to tissue kept in the dark. Lettuce tissue kept in air had a higher glucose-6-phosphate content than the CO2-treated lettuce. A hypothesis regarding alternate energy supply mechanisms for resistance of lettuce tissue to elevated CO2 injury is discussed.
42
Verburg, P. SJ, W. Cheng, D. W. Johnson, and D. E. Schorran. "Nonsymbiotic nitrogen fixation in 3-year-old Jeffrey pines and the role of elevated [CO2]." Canadian Journal of Forest Research 34, no. 9 (2004): 1979–84. http://dx.doi.org/10.1139/x04-077.
Full textAbstract:
Increased belowground labile C inputs under elevated [CO2] could stimulate nonsymbiotic N2 fixation, thereby enhancing growth responses of vegetation to elevated [CO2] on nutrient-poor sites. To test this hypothesis, nonsymbiotic N2 fixation rates in soils planted with 3-year-old Jeffrey pine (Pinus jeffreyi Grev. & Balf.) trees grown under 365 and 700 µL·L1 atmospheric [CO2] were measured by exposing the soil to 15N2-enriched air for 78 d. Nitrogen fixation rates were estimated by measuring 15N content of trees and soil. Compared with the ambient CO2 treatment, the elevated CO2 treatment did not affect biomass, N content, or δ15N of individual plant parts and soils, indicating that elevated [CO2] did not stimulate nonsymbiotic N2 fixation. Because belowground C inputs did not increase under elevated [CO2], the initial hypothesis could not be accepted or rejected. The results from the 15N2 labeling study agree with other studies showing that nonsymbiotic N2 fixation is not likely to provide a large input of N in forest ecosystems. The 15N2 labeling technique was promising for studying N2 fixation in plantsoil systems, but the preliminary nature of this study did not allow for firm conclusions with regard to the effects of elevated [CO2].
43
Breitbach, Elizabeth, and Victor Lai. "Elevated Ambient Carbon Dioxide Levels Induce Attraction but Not Attachment of Adult Ixodes scapularis in Artificial Membrane Feeding." McGill Science Undergraduate Research Journal 19, no. 1 (2024): 33–37. http://dx.doi.org/10.26443/msurj.v19i1.219.
Full textAbstract:
Numerous feeding studies on tick species have explored disease transmission, vector interactions, and acaricide testing. Traditionally, these studies used animals for feeding. However, artificial membrane feeding offers several advantages including increased standardization of experiments, decreased costs, and improved animal welfare. In vitro conditions must closely mimic natural environments to promote successful feeding attachment. Kairomones produced by the host are strong stimulants that encourage attachment. An important kairomone detected by ticks is carbon dioxide (CO2). Previous studies have shown elevated CO2 levels stimulate host identification and attraction and potentially improve artificial feeding rates in some tick species. The objective of this study was to use an artificial membrane feeding chamber prototype to explore the effects of ambient CO2 in inducing Ixodes scapularis attachment. Differences in attachment rate were explored at an air-typical ambient CO2 level of 0.04% and an elevated CO2 level of 4.0%. Tick attachment was not detected in either ambient CO2 condition during the incubation period, indicating ambient CO2 does not impact the attachment rate under the presented condition. However, I. scapularis contact with the artificial membrane occurred at an increased rate of 0.014 female ticks in contact with the membrane per hour in the elevated CO2 condition (4%) compared with a rate of 0.01 ticks per hour in the air-typical CO2 condition (0.04%) (p = 0.048) suggesting that the ambient CO2 level affects attraction to the blood but does not directly stimulate attachment of I. scapularis.
44
Umezuruike, Chinecherem, Halleluyah Aworinde, Goodness Amodu, Abidemi Adeniyi, Michael Rudolph, and Oluwasegun Aroba. "Campus air quality dataset." F1000Research 14 (April 3, 2025): 388. https://doi.org/10.12688/f1000research.162509.1.
Full textAbstract:
Background Elevated levels of carbon dioxide (CO2) within academic settings can adversely affect the health and academic efficacy of both students and faculty. High concentrations of CO2 are correlated with reduced cognitive functioning, compromised decision-making abilities, diminished academic performance, and various health-related issues. The escalating apprehensions regarding the detrimental health consequences of air pollution have precipitated an increase in research focused on air quality assessment and amelioration. Method The investigation utilized Internet of Things (IoT) devices that were outfitted with sensors to gather data on various environmental parameters, such as temperature, humidity, CO2 concentrations, and light intensity. This data underwent analysis through the application of summary statistics to delineate the dataset and to visualize the distribution of variables via scatter matrix plots. Result The dataset obtained, which encompasses essential air quality and environmental parameters, is now accessible to the public through the Mendeley repository. The analytical findings illuminated significant characteristics of the data concerning CO2 levels and their prospective ramifications on the academic milieu. Conclusion The amalgamation of IoT technology with summary statistical analysis presents a promising methodology for the real-time surveillance of air quality. This approach yields critical insights into the health and academic ramifications of heightened CO2 levels within educational environments, underscoring the necessity for ongoing air quality monitoring to enhance campus conditions.
45
Kader, A. A., D. Ke, M. Mateos, and E. Yahia. "ACTION OF REDUCED OXYGEN AND ELEVATED CARBON DIOXIDE ON ANAEROBIC METABOLISM OF `BARTLETT' PEARS." HortScience 27, no. 6 (1992): 603f—603. http://dx.doi.org/10.21273/hortsci.27.6.603f.
Full textAbstract:
Fruits of `Bartlett' pear (Pyrus communis L.) at green (preclimacteric) and yellow (postclimacteric) stages were kept in 0.25% O2 (balance N2), 80% CO2 (balance O2), or 0.25% O2 + 80% CO2 (balance N2) for 1, 2, or 3 days followed by transfer to air at 20C for 3 days to study the effects of these controlled atmosphere (CA) treatments on anaerobic products and enzymes. All the three CA treatments caused greater accumulation of ethanol, acetaldehyde, and ethyl acetate than the air control. The postclimacteric pears were more sensitive to CA treatments as indicated by occurrence of skin browning, enhanced activity of pyruvate decarboxylase, and higher concentrations of the anaerobic volatiles. For the preclimacteric pears, the 0.25% O2 treatment dramatically increased alcohol dehydrogenase (ADH) activity, which was associated with the induction of one ADH isozyme. Exposure of preclimacteric pears to 80% CO2 slightly increased ADH activity while treatment with 0.25% O2 + 80% CO2 resulted in lower AD11 activity than 0.25% O2 alone.
46
ESHGHIZADEH, Hamid Reza, Morteza ZAHEDI, and Samaneh MOHAMMADI. "Differential Growth Responses of Wheat Seedlings to Elevated CO2." Notulae Scientia Biologicae 10, no. 3 (2018): 400–409. http://dx.doi.org/10.15835/nsb10310286.
Full textAbstract:
Intraspecific variations in wheat growth responses to elevated CO2 was evaluated using 20 Iranian bread wheat (Triticum aestivum L.) cultivars. The plants were grown in the modified Hoagland nutrient solution at a greenhouse until 35 days of age using two levels of CO2 (~380 and 700 µmol mol–1). The shoot and root dry weights of the wheat cultivars exhibited average enhancements of 17% and 36%, respectively, under elevated CO2. This increase was associated with higher levels of chlorophyll a (25%), chlorophyll b (21%), carotenoid (30%), leaf area (54%) and plant height (49.9%). The leaf area (r = 0.69**), shoot N content (r = 0.62**), plant height (r = 0.60**) and root volume (r = 0.53*) were found to have important roles in dry matter accumulation of tested wheat cultivars under elevated CO2 concentration. However, responses to elevated CO2 were considerably cultivar-dependent. Based on the stress susceptibility index (SSI) and stress tolerance index (STI), the wheat cultivars exhibiting the best response to elevated CO2 content were ‘Sistan’, ‘Navid’, ‘Shiraz’, ‘Sepahan’ and ‘Bahar’, while the ones with poor responses were ‘Omid’, ‘Marun’, ‘Sorkhtokhm’ and ‘Tajan’. The findings from the present experiment showed significant variation among the Iranian wheat cultivars in terms of their responses to elevated air CO2, providing the opportunity to select the most efficient ones for breeding purposes.
47
Kumeleh, Abbas Shahdi, P. Sharmila, D. C. Uprety, and P. P. Saradhi. "Effects of elevated CO2 on soil physicochemical characteristics under Free Air CO2 Enrichment (FACE) technology." IOP Conference Series: Earth and Environmental Science 6, no. 29 (2009): 292045. http://dx.doi.org/10.1088/1755-1307/6/29/292045.
Full text
48
Schortemeyer, Marcus, Owen K. Atkin, Nola McFarlane, and John R. Evans. "The impact of elevated atmospheric CO2 and nitrate supply on growth, biomass allocation, nitrogen partitioning and N2 fixation of Acacia melanoxylon." Functional Plant Biology 26, no. 8 (1999): 737. http://dx.doi.org/10.1071/pp99062.
Full textAbstract:
The interactive effects of nitrate supply and atmospheric CO2 concentration on growth, N2 fixation, dry matter and nitrogen partitioning in the leguminous tree Acacia melanoxylon R.Br. were studied. Seedlings were grown hydroponically in controlled-environment cabinets for 5 weeks at seven 15N-labelled nitrate levels, ranging from 3 to 6400 mmol m–3. Plants were exposed to ambient (~350 µmol mol–1) or elevated (~700 µmol mol–1) atmospheric CO2 for 6 weeks. Total plant dry mass increased strongly with nitrate supply. The proportion of nitrogen derived from air decreased with increasing nitrate supply. Plants grown under either ambient or elevated CO2 fixed the same amount of nitrogen per unit nodule dry mass (16.6 mmol N per g nodule dry mass) regardless of the nitrogen treatment. CO2 concentration had no effect on the relative contribution of N2 fixation to the nitrogen yield of plants. Plants grown with ≥50 mmol m–3 N and elevated CO2 had approximately twice the dry mass of those grown with ambient CO2 after 42 days. The rates of net CO2 assimilation under growth conditions were higher per unit leaf area for plants grown under elevated CO2. Elevated CO2 also decreased specific foliage area, due to an increase in foliage thickness and density. Dry matter partitioning between plant organs was affected by ontogeny and nitrogen status of the plants, but not by CO2 concentration. In contrast, plants grown under elevated CO2 partitioned more of their nitrogen to roots. This could be attributed to reduced nitrogen concentrations in foliage grown under elevated CO2.
49
Syvertsen, J. P. "Elevated CO2 Increases Growth and Photosynthetic Efficiency of Citrus Rootstock Seedlings." HortScience 32, no. 3 (1997): 531B—531. http://dx.doi.org/10.21273/hortsci.32.3.531b.
Full textAbstract:
The objectives of these greenhouse experiments were to determine the effects of elevated CO2 on growth, mineral nutrition, and gas exchange physiology of seedlings of four commercial Citrus rootstocks. We grew well-watered and fertilized seedlings of `Volkamer' lemon (VL), `Cleopatra' mandarin (CL), `Swingle' citrumelo (SW), and `Troyer' citrange (TC) cultivars (in decreasing order of vigor) in unshaded, air-conditioned greenhouses at ambient CO2 (350 μmol/mol) or 2x ambient CO2 for 5 months. CL was the smallest cultivar, had the lowest root/shoot (r/s) ratio,and lowest rates of CO2 assimilation (A) of leaves, transpiration (E), and water-use efficiency, (A/E). Overall, daily whole-plant water use was correlated with single-leaf E. Elevated CO2 increased both shoot and root growth similarly; therefore, r/s was not affected. Elevated CO2 increased A, leaf dry wt/area, and leaf C, but decreased transpiration and leaf N so that leaf C/N, A/N, and A/E all increased. Although plant size of the four cultivars ranked similarly at both ambient and high CO2, the more-vigorous cultivars grew proportionately more at high CO2 than the less-vigorous cultivars. Growing cultivars at elevated CO2 can yield insights into mechanisms determining vigor and relationships between A and plant growth.
50
Johnson, M. G., D. L. Phillips, D. T. Tingey, and M. J. Storm. "Effects of elevated CO2, N-fertilization, and season on survival of ponderosa pine fine roots." Canadian Journal of Forest Research 30, no. 2 (2000): 220–28. http://dx.doi.org/10.1139/x99-199.
Full textAbstract:
We used minirhizotrons to assess the effects of elevated CO2, N, and season on the life-span of ponderosa pine (Pinus ponderosa Dougl. ex Laws.) fine roots. CO2 levels were ambient air (A), ambient air + 175 µmol·mol-1 (A + 175) and ambient air + 350 µmol·mol-1 (A + 350). N treatments were 0, 100, and 200 kg N·ha-1 per year (N0, N100, and N200, respectively). Fine root survival was strongly influenced by season and seemed to be most strongly linked to soil temperature. Roots born in the fall and winter had longer median root life-span (MRLs) than those born during the spring and summer. Elevated CO2 increased root life-span, but N fertilization decreased it. Under A, MRL was 74 ± 12 days (mean ± SE) and was significantly different from the MRL for the A + 350 treatment (102 ± 14 days). MRL under A + 175 averaged 92 ± 10 days. MRL was 116 ± 13 days for the N0 treatment and was significantly greater than MRL for the N100 (70 ± 10 days) and N200 (62 ± 14 days) treatments. Assuming that longer lived fine roots continue their resource acquisition functions, then elevated CO2 may have the effect of extending the resource acquisition period. In contrast, fine roots in N-rich environments have shorter life-spans than fine roots in N-poor environments.