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Variations in chlorophyll content, stomatal conductance, and photosynthesis in Setaria EMS mutants 被引量:2
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作者 TANG Chan-juan LUO Ming-zhao +5 位作者 ZHANG Shuo JIA Guan-qing TANG Sha JIA Yan-chao ZHI Hui DIAO Xian-min 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2023年第6期1618-1630,共13页
Chlorophyll (Chl) content,especially Chl b content,and stomatal conductance (G_s) are the key factors affecting the net photosynthetic rate (P_n).Setaria italica,a diploid C_4 panicoid species with a simple genome and... Chlorophyll (Chl) content,especially Chl b content,and stomatal conductance (G_s) are the key factors affecting the net photosynthetic rate (P_n).Setaria italica,a diploid C_4 panicoid species with a simple genome and high transformation efficiency,has been widely accepted as a model in photosynthesis and drought-tolerance research.The current study characterized Chl content,G_s,and P_n of 48 Setaria mutants induced by ethyl methanesulfonate.A total of 24,34,and 35 mutants had significant variations in Chl content,G_s,and P_n,respectively.Correlation analysis showed a positive correlation between increased G_s and increased P_n,and a weak correlation between decreased Chl b content and decreased P_n was also found.Remarkably,two mutants behaved with significantly decreased Chl b content but increased P_n compared to Yugu 1.Seven mutants behaved with significantly decreased G_s but did not decrease P_(n )compared to Yugu 1.The current study thus identified various genetic lines,further exploration of which would be beneficial to elucidate the relationship between Chl content,G_s,and P_n and the mechanism underlying why C_4 species are efficient at photosynthesis and water saving. 展开更多
关键词 photosynthetic capacity chlorophyll content stomatal conductance EMS mutant variation Setaria italica
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Comparison of the S-, N- or P-Deprivations’ Impacts on Stomatal Conductance, Transpiration and Photosynthetic Rate of Young Maize Leaves 被引量:1
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作者 Dimitris L. Bouranis Styliani N. Chorianopoulou +4 位作者 Alexandros Dionias Giouli Sofianou Aristotelis Thanasoulas Georgios Liakopoulos Dimosthenis Nikolopoulos 《American Journal of Plant Sciences》 2012年第8期1058-1065,共8页
Seven-day-old maize (Zea mays) plants were grown hydroponically for ten days in deprived nutrient solutions against the corresponding control grown under full nutrition;the effects of S-, N- or P-deprivation on lamina... Seven-day-old maize (Zea mays) plants were grown hydroponically for ten days in deprived nutrient solutions against the corresponding control grown under full nutrition;the effects of S-, N- or P-deprivation on laminas’ mean stomatal conductance (gs), transpiration rate (E) and photosynthetic rate (A) were monitored, along with the impact on the laminas’ total dry mass (DM), water amount (W), length and surface area (Sa). Furthermore, a time series analysis of each parameter’s response ratios (Rr), i.e. the treatment’s value divided by the corresponding control’s one, was performed. Under S-deprivation, the Rr of laminas’ mean gs, E, and A presented oscillations within a ±15% fluctuation zone, notably the “control” zone, whilst those of laminas’ total DM, water amount, surface area, and length included oscillation during the first days and deviation later on, presenting deviation during d10. Under the N-deprivation conditions all Rr time courses except the A one, included early deviations from the control zone without recovering. The deviation from the control zone appeared at d4. Under P-deprivation, all Rr time courses represented oscillations within the control zone. P-deprivation’s patterns resembled those of S-deprivation. Compared to the one of the S-deprivation, the P-one’s oscillations took place within a broader zone. Linear relationships among the various Rr patterns were found between gs-E, gs-A, E-A, DM-W and DM-Sa. In conclusion, the impact of P-deprivation appeared in an early stage and included an alleviation action, the one of N-deprivation appeared early with no alleviation action, whilst that of S-deprivation appeared later, being rather weaker when compared to the impact of the P-deprivation’s impact. 展开更多
关键词 S-Deprivation N-Deprivation P-Deprivation Hydroponics Zea Mays stomatal conductance TRANSPIRATION RATE photosynthetic RATE Response Ratios Fluctuation Analysis
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Response of stomatal conductance of two tree species to vapor pressure deficit in three climate zones 被引量:4
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作者 Jing LI XiaoMing LI 《Journal of Arid Land》 SCIE CSCD 2014年第6期771-781,共11页
Stomatal behavior is a central topic of plant ecophysiological research under global environmental change. However, the physiological mechanism controlling the response of stomata to vapor pressure deficit (VPD) or ... Stomatal behavior is a central topic of plant ecophysiological research under global environmental change. However, the physiological mechanism controlling the response of stomata to vapor pressure deficit (VPD) or relative humidity (RH) has been inadequately understood till now. In this study, responses of stomatal conduc- tance (gs) to VPD in two species of trees (Fraxinus chinensis Roxb., Populus alba L. var. pyramidalis Bge.)in three different climate zones (Jinan with typical warm humid/semi-humid climate, Urumqi with temperate continental arid climate and Turpan with extreme arid desert climate) were measured. Levels of two phytohormones (abscisic acid, ABA; indole-3-acetic acid, IAA) in the leaves of the two tree species at these three sites were also measured by high performance liquid chromatography. The results showed that the responses of gs to an increasing VPD in these two tree species at the three sites had peak curves which could be fitted with a Log Normal Model (gs=a.exp(-O.5(In(DIc)lb)2). The VPD/RH values corresponding to the maximum g, can be calculated using the fitting models for the two tree species in the three sites. We found that the calculated g, -VPD correlated nega- tively with relative air humidity in the three sites during the plant growth period (April to October 2010), which showed the values of g,-max-VPD were related to the climate conditions. The prevailing empirical stomatal model (Leuning model) and optimal stomatal behavior model could not properly simulate our measured data. The water use efficiency in the two tree species did not show obvious differences under three very different climatic conditions, but the highest gs, photosynthetic and transpiration rates occurred in P. alba var. of Turpan. The sensitivity in re- sponse of g~ to VPD in leaves of the two trees showed positive correlations with the concentration of ABA, which implied that ABA level could be used as an indicator of the sensitivity of stomatal response to VPD. Our results confirmed that the prediction of the response of gs to VPD might be incomplete in the two current popular models. Therefore, an improved g, model which is able to integrate the results is needed. Also, the stomatal response mechanism of single peak curves of g~ to VPD should be considered. 展开更多
关键词 abscisic acid relative humidity stomatal conductance stomatal model vapor pressure deficit
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Drought-Induced Changes in Xylem Sap pH, ABA and Stomatal Conductance 被引量:2
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作者 GUOXiu-lin LIUZi-hui +1 位作者 Razzaq LIGuang-min 《Agricultural Sciences in China》 CAS CSCD 2004年第7期496-501,共6页
Upstream signals potentially regulating evaporation and stomatal conductance wereinvestigated using 6-8-leaf-old maize (Zea may L.) seedlings which were grown in agreenhouse. Pressure chamber was used to measure leaf ... Upstream signals potentially regulating evaporation and stomatal conductance wereinvestigated using 6-8-leaf-old maize (Zea may L.) seedlings which were grown in agreenhouse. Pressure chamber was used to measure leaf water potential and to collectxylem sap. The pH of xylem sap in stems was higher than that in root, and the abscisicacid (ABA) concentration in stems was the highest in well-watered seedlings. The ABAconcentration and pH of xylem sap in roots, stems and leaves increased, and the ABAconcentration in leaves reached the maximum during drought stress. The treatment ofroots with exogenous ABA solution (100molL-1) increased xylem sap ABA concentration inall organs measured, and induced stomatal closure, but did not change ABA distributionamong organs of maize seedlings. The combined effects of external pH buffer on pH, ABAof xylem sap and stomatal behavior indicated that pH, as a root-source signal to leavesunder drought stress, regulated stomatal closure through accumulating ABA in leaves orguard cells. 展开更多
关键词 DROUGHT Abscisic acid PH Xylem sap SIGNAL stomatal conductance
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Study on Transpiration and Stomatal Conductance Characteristics of C3 and C4 Plant 被引量:1
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作者 MENG Jinghui LU Yuanchang +1 位作者 Ronald Kohne LIU Gang 《Journal of Northeast Agricultural University(English Edition)》 CAS 2009年第4期1-8,共8页
The transpiration experiment was done under greenhouse conditions with a C3 plant sweet pepper (Capsicum annuum Linn.) and two C4 plants, sorghum (Sorghum bicolor L.Moench) and maize (Zea mays Linn.). Three spec... The transpiration experiment was done under greenhouse conditions with a C3 plant sweet pepper (Capsicum annuum Linn.) and two C4 plants, sorghum (Sorghum bicolor L.Moench) and maize (Zea mays Linn.). Three species were irrigated with three different water treatment levels of 100%, 66% and 33% which gave a comparison of tolerance and adaptation to irrigation and two different levels of water stress. The measurements of transpiration rate and stomatal conductance were done between 8.00 a.m. and 16.00 p.m. with measurements about each 1.5 h with an infrared gas analyzer. The results showed that Z. mays probably due to a higher leaf area had very low values and was significantly different (LSD pairwise comparison) from C. annuum and S. bicolor. The hypotheses that C4 plants and C3 plants have different transpiration rates and stomatal conductance could not be shown with the results. However, the hypotheses that for the same species, the highest values in transpiration rate and stomatal conductance were with the 100% irrigation treatment and the lowest values were with the 33% irrigation treatment could be accepted due to the results of this trial. 展开更多
关键词 transpiration rate stomatal conductance water stress
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Distribution Profiles and Interrelations of Stomatal Conductance, Transpiration Rate and Water Dynamics in Young Maize Laminas under Nitrogen Deprivation
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作者 Dimitris L. Bouranis Alexandros Dionias +2 位作者 Styliani N. Chorianopoulou Georgios Liakopoulos Dimosthenis Nikolopoulos 《American Journal of Plant Sciences》 2014年第5期659-670,共12页
Seven-day-old maize (Zea mays) plants were grown hydroponically for ten days in N-deprived nutrient solution. The distribution profiles according to the position on the stem of the –N laminas stomatal conductance, tr... Seven-day-old maize (Zea mays) plants were grown hydroponically for ten days in N-deprived nutrient solution. The distribution profiles according to the position on the stem of the –N laminas stomatal conductance, transpiration rate, photosynthetic rate (1st-group) were monitored, along with the corresponding profiles of dry mass, water amount, water content, length, surface area, and specific surface area (2nd-group), relative to control. In the uppermost –N laminas, the changes within a parameter of the 1st-group were significantly higher and of the 2nd-group significantly lower than the control, respectively. Correlations of the corresponding values among the parameters of the 1st-or 2nd-group were linear. The parameters between groups correlated non-linearly. Transpiration rate was divided by the lamina’s dry mass correlated with surface area in a power-type function. The slopes of the response ratios linear relations between the various pairs of parameters could be used for simulation of a lamina’s response to the deprivation. 展开更多
关键词 N-Deprivation HYDROPONICS ZEA mays stomatal conductance TRANSPIRATION RATE photosynthetic RATE Response Ratios
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Verification of the stomatal conductance of Nebbiolo grapevine
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作者 Stefania PRINO Federico SPANNA Claudio CASSARDO 《Journal of Chongqing University》 CAS 2009年第1期17-24,共8页
Wine is one of the most important Italian export products,and Nebbiolo is one of the most respected Italian grapes. In the summer of 2007,a measurement campaign was carried out in a Nebbiolo vineyard located in Vezza ... Wine is one of the most important Italian export products,and Nebbiolo is one of the most respected Italian grapes. In the summer of 2007,a measurement campaign was carried out in a Nebbiolo vineyard located in Vezza d’Alba,near Cuneo,Italy. Using a gauge of trade gases and some other instruments,we recorded the stomatal conductance and also some physiological parameters useful for estimating the dependence of stomatal conductance on environmental variables. The goal of this experiment was improving the parameterization of grapevine evapotranspiration through the assessment of the stomatal conductance and,in particular,of the functional dependence of the stomatal conductance on the following variables:the photosynthetically active radiation,the atmospheric temperature,the atmospheric moisture deficit,and the carbon dioxide concentration. The observations allowed us to check and,in some cases,to adapt the existing general parameterizations found in literature. The results showed some significant differences with the existing parameterizations concerning the atmospheric temperature,the atmospheric moisture deficit,and the carbon dioxide concentration. The parameterizations obtained in this experiment,although referring to a specific plant and site(namely the Nebbiolo at Vezza d’Alba),could allow assessment of the best environmental conditions under which the Nebbiolo grapevine production is the best,and in future could be tested for other grapevines or climates. 展开更多
关键词 GRAPEVINE EVAPOTRANSPIRATION stomatal conductance photosynthetically active radiation
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Photosynthetic response dynamics in the invasive species Tithonia diversifolia and two co-occurring native shrub species under fluctuating light conditions
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作者 Ju Li Shu-Bin Zhang Yang-Ping Li 《Plant Diversity》 SCIE CAS CSCD 2024年第2期265-273,共9页
To determine the invasiveness of invasive plants,many studies have compared photosynthetic traits or strategies between invasive and native species.However,few studies have compared the photosynthetic dynamics between... To determine the invasiveness of invasive plants,many studies have compared photosynthetic traits or strategies between invasive and native species.However,few studies have compared the photosynthetic dynamics between invasive and native species during light fluctuations.We compared photosynthetic induction,relaxation dynamics and leaf traits between the invasive species,Tithonia diversifolia and two native species,Clerodendrum bungei and Blumea balsamifera,in full-sun and shady habitats.The photosynthetic dynamics and leaf traits differed among species.T.diversifolia showed a slower induction speed and stomatal opening response but had higher average intrinsic water-use efficiency than the two native species in full-sun habitats.Thus,the slow induction response may be attributed to the longer stomatal length in T.diversifolia.Habitat had a significant effect on photosynthetic dynamics in T.diversifolia and B.balsamifera but not in C.bungei.In shady habitat,T.diversifolia had a faster photosynthetic induction response than in full-sun habitat,leading to a higher average stomatal conductance during photosynthetic induction in T.diversifolia than in the two native species.In contrast,B.balsamifera had a larger stomatal length and slower photosynthetic induction and relaxation response in shady habitat than in full-sun habitat,resulting in higher carbon gain during photosynthetic relaxation.Nevertheless,in both habitats,T.diversifolia had an overall higher carbon gain during light fluctuations than the two native species.Our results indicated that T.diversifolia can adopt more effective response strategies under fluctuating light environments to maximize carbon gain,which may contribute to its successful invasion. 展开更多
关键词 Invasive plant photosynthetic induction photosynthetic relaxation Carbon gain stomatal traits Tithonia diversifolia
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SIMULATION OF THE PHYSIOLOGICAL RESPONSES OF C 3 PLANT LEAVES TO ENVIRONMENTAL FACTORS BY A MODEL WHICH COMBINES STOMATAL CONDUCTANCE, PHOTOSYNTHESIS AND TRANSPIRATION 被引量:41
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作者 于强 王天铎 《Acta Botanica Sinica》 CSCD 1998年第8期740-754,共15页
Transpiration element is included in the integrated stomatal conductance photosynthesis model by considering gaseous transfer processes, so the present model is capable to simulate the influence of boundary layer con... Transpiration element is included in the integrated stomatal conductance photosynthesis model by considering gaseous transfer processes, so the present model is capable to simulate the influence of boundary layer conductance. Leuning in his revised Ball's model replaced relative humidity with VPD s (the vapor pressure deficit from stomatal pore to leaf surface) and thereby made the relation with transpiration more straightforward, and made it possible for the regulation of transpiration and the influence of boundary layer conductance to be integrated into the combined model. If the differences in water vapor and CO 2 concentration between leaf and ambient air are considered, VPD s , the evaporative demand, is influenced by stomatal and boundary layer conductance. The physiological responses of photosynthesis, transpiration, and stomatal function, and the changes of intercellular CO 2 and water use efficiency to environmental factors, such as wind speed, photon flux density, leaf temperature and ambient CO 2, are analyzed. It is shown that if the boundary layer conductance drops to a level comparable with stomatal conductance, the results of simulation by the model presented here differ significantly from those by the previous model, and, in some cases, are more realistic than the latter. 展开更多
关键词 PHOTOSYNTHESIS TRANSPIRATION stomatal conductance Boundary layer conductance Integrated model
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Effect of Water Deficit Stress on Photosynthetic Characteristics of Jatropha curcas
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作者 Kesego Makholwa Baleseng Moseki Goitseone Malambane 《American Journal of Plant Sciences》 CAS 2023年第1期104-112,共9页
The need to mitigate climate change cannot be more emphasized, which arises, as a result of increases in CO<sub>2</sub> emissions due to anthropogenic activities. Given the current world energy problems of... The need to mitigate climate change cannot be more emphasized, which arises, as a result of increases in CO<sub>2</sub> emissions due to anthropogenic activities. Given the current world energy problems of high fossil fuel consumption which plays a pivotal role in the greenhouse effect, Jatropha curcas biodiesel has been considered a potential alternative source of clean energy (biodiesel is carbon neutral). However, the ability of Jatropha curcas, as a candidate source of alternative of clean energy, to grow in marginal and dry soils, has been poorly elucidated. This study, therefore aimed at investigating whether Jatropha curcas leaves could switch from carrying out C<sub>3</sub> photosynthetic pathway to Crassulacean Acid Metabolism (CAM) as a strategy to improve its water deficit tolerance. Thirty-five-day-old Jatropha curcas accessions, from three different climatic zones of Botswana, viz., Mmadinare (Central zone), Thamaga (Southern zone) and Maun (Northern zone), were subjected to water stress, by with-holding irrigation with half-strength Hoagland culture solution. Net photosynthetic rate, transpiration and stomatal conductance were measured at weekly intervals. The leaf pH was measured to determine whether there was a decrease in pH (leaf acidification) of the leaves during the night, when the plants experienced water deficit stress. All the accessions exhibited marked reduction in all the measured photosynthetic characteristics when experience water deficit stress. However, a measurable CO<sub>2</sub> uptake was carried out by leaves of all the accessions, in the wake of marked decreases in stomatal conductance. There is evidence to suggest that when exposed to water stress J. curcas accessions switch from C<sub>3</sub> mode of photosynthesis to CAM photosynthetic pathway. This is attested to by the slightly low leaf pH at night. Thamaga accession exhibited an earlier stomatal closure than the other two accessions. This resulted in Thamaga accession displaying a slightly lower dry weight than both Mmadinare and Maun accessions. It could be concluded that Jatropha curcas appeared to tolerate water deficit stress due to its ability of switching from C<sub>3</sub> photosynthetic pathway to the CAM photosynthetic pathway, but with a cost to biomass accumulation, as demonstrated by slightly more reduced CO<sub>2</sub> assimilation by Thamaga accession, than the other two accessions. 展开更多
关键词 Jatropha curcas BIODIESEL Crassulacean Acid Metabolism net photosynthetic Rate stomatal conductance
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Application and comparison of winter wheat canopy resistance estimation models based on the scaling-up of leaf stomatal conductance 被引量:6
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作者 WEI Zheng LIU Yu +2 位作者 XU Di CAI JiaBing ZHANG BaoZhong 《Chinese Science Bulletin》 SCIE EI CAS 2013年第23期2909-2916,共8页
Canopy resistance estimation model based on the scaling-up leaf stomatal resistance is the focus of evapotrantion research, as there is a need to select the proper scaling-up model for winter wheat in typical areas of... Canopy resistance estimation model based on the scaling-up leaf stomatal resistance is the focus of evapotrantion research, as there is a need to select the proper scaling-up model for winter wheat in typical areas of North China. Two years of field experimental data are used for the Leuning-Ball and Jarvis stomatal model calibration and validation, canopy resistance estimation models are established based on Leuning-Ball and Jarvis stomatal models, their application effects are compared and verified. Results show that daily variation of stomatal resistance of winter wheat is higher than that of canopy resistance, and there exists scale differences between leaf and canopy scale; Leuning-Ball stomatal model can be better explicated by the response of stomatal conductance towards environmental factors; Leuning-Ball canopy resistance estimation models turn out to be an effective canopy resistance simulation, and thus can be applied to research on the scaling-up of vapor transmission resistance of winter wheat in typical areas of North China. 展开更多
关键词 叶片气孔导度 冠层阻力 估算模型 冬小麦 基础 应用 叶片气孔阻力 中国北方地区
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Responses of leaf stomatal and mesophyll conductance to abiotic stress factors 被引量:1
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作者 LI Sheng-lan TAN Ting-ting +9 位作者 FAN Yuan-fang Muhammad Ali RAZA WANG Zhong-lin WANG Bei-bei ZHANG Jia-wei TAN Xian-ming CHEN Ping Iram SHAFIQ YANG Wen-yu YANG Feng 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2022年第10期2787-2804,共18页
Plant photosynthesis assimilates CO_(2)from the atmosphere,and CO_(2)diffusion efficiency is mainly constrained by stomatal and mesophyll resistance.The stomatal and mesophyll conductance of plants are sensitive to ab... Plant photosynthesis assimilates CO_(2)from the atmosphere,and CO_(2)diffusion efficiency is mainly constrained by stomatal and mesophyll resistance.The stomatal and mesophyll conductance of plants are sensitive to abiotic stress factors,which affect the CO_(2)concentrations at carboxylation sites to control photosynthetic rates.Early studies conducted relevant reviews on the responses of stomatal conductance to the environment and the limitations of mesophyll conductance by internal structure and biochemical factors.However,reviews on the abiotic stress factors that systematically regulate plant CO_(2)diffusion are rare.Therefore,in this review,the rapid and long-term responses of stomatal and mesophyll conductance to abiotic stress factors(such as light intensity,drought,CO_(2)concentration and temperature)and their physiological mechanisms are summarized.Finally,future research trends are also investigated. 展开更多
关键词 CO_(2)diffusion abiotic stress factors stomatal conductance mesophyll conductance
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Combining sap flow measurement-based canopy stomatal conductance and ^(13)C discrimination to estimate forest carbon assimilation 被引量:9
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作者 ZHAO Ping LU Ping +4 位作者 MA Ling SUN Guchou RAO Xingquan CAI Xi'an ZENG Xiaoping 《Chinese Science Bulletin》 SCIE EI CAS 2005年第18期2021-2027,共7页
The available methods for studying C uptake of forest and their problems in practices are reviewed, and a new approach to combining sap flow and 13C techniques is proposed in this paper. This approach, obtained throug... The available methods for studying C uptake of forest and their problems in practices are reviewed, and a new approach to combining sap flow and 13C techniques is proposed in this paper. This approach, obtained through strict mathematic derivation, combines sap flow measure-ment-based canopy stomatal conductance and 13C discrimi-nation to estimate instantaneous carbon assimilation rate of a forest. Namely the mean canopy stomatal conductance (gc) acquired from accurate measurement of sap flux density is integrated with the relationship between 13C discrimination (?) and Ci/Ca (intercellular/ambient CO2 concentrations) and with that between Anet (net photosynthetic rate) and gCO2 (stomatal conductance for CO2) so that a new relation be-tween forest C uptake and ? as well as gc is established. It is a new method of such kind for studying the C exchange be-tween forest and atmosphere based on experimental ecology. 展开更多
关键词 碳同位素 稳定性 碳同化 热量消散探测 电导系数
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Gas flaring cause shifts in mesophyll and stomatal functional traits of Betula pubescens Ehrh.
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作者 Dina A.Ronzhina Svetlana V.Migalina Irek A.Yusupov 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第6期2079-2087,共9页
In petroleum-producing territories of West Siberia(Russia),oil well gas flares have a thermal effect on nearby plant communities.Such communities can be used as models for studying plant acclimation to global warming.... In petroleum-producing territories of West Siberia(Russia),oil well gas flares have a thermal effect on nearby plant communities.Such communities can be used as models for studying plant acclimation to global warming.In the present study on the effect of the hydrothermal regime at the flare sites on mesophyll and stomatal functional traits of Betula pubescens,leaves were collected from trees at250 m(control site[CS]),200,150 and 100 m(maximum impact site[MIS])from a flare.From the CS to MIS site,the average annual air temperature increased by 0.5℃and bog water level decreased by 17 cm.On plants from the MIS,stomata were 16%smaller and density was 20%lower compared to those at the CS,resulting in lower maximum stomatal conductance in plants from the MIS(mean±SE:MIS 0.84±0.05 mol·m^(-2)s^(-1),CS 1.24±0.06 mol·m^(-2)s^(-1);F=12.6,P<0.01).Mesophyll cell volume was 1.9 times lower at MIS than at CS.Chloroplast numbers per cell also declined with distance from the flares,from 21(MIS)to18(CS;F=15.6,P<0.001),and chloroplast volume was 24%higher at the CS,whereas the number of mesophyll cells and chloroplasts numbers per unit leaf area were 1.9 and 1.8 times higher at the MIS than at the CS,respectively.As a result,leaves from the MIS had a large total mesophyll cell(Ames/A)and chloroplast(Achl/A)surface area per unit leaf area,resulting in a 46%increase in mesophyll conductance in plants from the MIS.Thus,structural changes in leaf epidermis consisted of a decrease in stomatal size and number,could lower transpiration losses with higher temperatures and less water.To compensate for the reduction in leaf conductance due to a decrease in stomatal conductance under these conditions,an increase in the number of mesophyll cells and chloroplasts per unit area provides a greater gas-exchange area and mesophyll conductance. 展开更多
关键词 Leaf traits Mesophyll cell volume Chloroplast numbers Mesophyll conductance stomatal conductance
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Hydraulic role in differential stomatal behaviors at two contrasting elevations in three dominant tree species of a mixed coniferous and broad-leaved forest in low subtropical China
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作者 Liwei Zhu Tianyu Fu +4 位作者 Jie Du Weiting Hu Yanqiong Li Xiuhua Zhao Ping Zhao 《Forest Ecosystems》 SCIE CSCD 2023年第1期102-112,共11页
Quantifying the variation in stomatal behavior and functional traits of trees with elevation can provide a better understanding of the adaptative strategies to a changing climate. In this study, six water-and carbon-r... Quantifying the variation in stomatal behavior and functional traits of trees with elevation can provide a better understanding of the adaptative strategies to a changing climate. In this study, six water-and carbon-related functional traits were examined for three dominant tree species, Schima superba, Pinus massoniana and Castanopsis chinensis, in a mixed coniferous and broad-leaved forest at two elevations(70 and 360 m above sea level,respectively) in low subtropical China. We hypothesized that trees at higher elevations would develop more efficient strategies of stomatal regulations and greater water transport capacity to cope with more variable hydrothermal conditions than those at lower elevations. Results show that the hydraulic conductivity did not differ between trees at the two elevations, contrary to our expectation. The C. chinensis trees had greater values of leaf mass per unit area(LMA), and the S. superba and C. chinensis trees had greater values of wood density(WD),relative stem water content(RWC), and ratio of sapwood area to leaf area(Hv) at the 360-m elevation than at 70-m elevation. The mean canopy stomatal conductance was greater and more sensitive to vapor deficit pressure at360 m than at 70 m for both S. superba and C. chinensis, while stomatal sensitivity did not differ between the two contrasting elevations for P. massoniana. The midday leaf water potential(ψL) in P. massoniana was significantly more negative at 360 m than at 70 m, but did not vary with increasing elevation in both S. superba and C. chinensis.Variations in Hvcan be related to the differential stomatal behaviors between the two elevations. The variations of stomatal behavior and ψLwith elevation suggested the isohydric strategy for the two broad-leaved species and the anisohydric strategy for the conifer species. The species-specific differences in LMA, WD, RWC, and Hvbetween the two elevations may reflect conservative resource use strategies at the higher elevation. Our findings revealed a close relationship between hydraulic and stomatal behavior and may help better understand the functional responses of forests to changing environmental conditions. 展开更多
关键词 Sap flux stomatal conductance Leaf water potential Vapor pressure deficit ELEVATION Low subtropical China
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Seasonal Changes in Photosynthetic Characteristics of Ammopiptanthus mongolicus 被引量:43
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作者 李文瑞 冯金朝 +2 位作者 江天然 张立新 刘新民 《Acta Botanica Sinica》 CSCD 1999年第2期190-193,共4页
Seasonal changes in the photosynthetic characteristics of Ammopiptantus mongolicus (Maxim. )Chen f. were studied. When the net photosynthetic rate decreased with the elevation of air temperature, thestomatal conductan... Seasonal changes in the photosynthetic characteristics of Ammopiptantus mongolicus (Maxim. )Chen f. were studied. When the net photosynthetic rate decreased with the elevation of air temperature, thestomatal conductance and stomatal limitation value tended to decline simultaneously, while the interoellularCO2 concentration was increased. According to the two criteria discriminating the stomatal limitation of Photosynthesis suggeSted by Fmrquhar and Sharkey, the seasonal changes in these parameters indicated that the decrease in Pn may not be due to stomatal factor. These studies proved that the relative contents of the large subunit of Rubisco and the photochemical activities correlated with the seasonal changes in the net photosyntheticrate, whieh may show that these two factors contribute primarily to the seasonal changeS in CO2 assimilation. 展开更多
关键词 net photosynthetic rate stomatal conductance Intercellular CO2 concentration stomatal limitation value RUBISCO Electron transport activity
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Studies on Photosynthetic Characteristics of Tomato Leaves after Inoculation with Tomato Powdery Mildew (Oidium neolycopersici) 被引量:1
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作者 吴昊 董华芳 许延波 《Plant Diseases and Pests》 CAS 2011年第2期9-11,21,共4页
[ Objective ] The paper was to explore the pathogenic mechanism of tomato powdery mildew, and to study the effects of the disease on photosynthetic characteristics of tomato. [ Method ] With four tomato varieties as m... [ Objective ] The paper was to explore the pathogenic mechanism of tomato powdery mildew, and to study the effects of the disease on photosynthetic characteristics of tomato. [ Method ] With four tomato varieties as materials, the pathogen of tomato powdery mildew was artificially inoculated. After the varieties were infected, the parameters including net photosynthetic rate, stomatal conductance and transpiration rate of tomato leaf were measured by Li-6400 portable photo- synthesis detector under natural lighting conditions. [ Result] The net photosynthetic rate, stomatal conductance and transpiration rate of four tomato varieties all decreased after infection. However, the decrease extent of these parameters of four varieties was different. The parameters of seriously damaged Jinyangdajuxdng ( No. 4) and Xinsheng No. 1 ( No. 5 ) decreased greatly, while the parameters of slightly damaged Lujia ( No. 13 ) and improved 98-6 decreased lightly. [ Condu- sion] The results could provide theoretical basis for the study on pathogenic mechanism, new prevention way and resistance breeding of tomato powdery mildew. 展开更多
关键词 Tomato powdery mildew net photosynthetic rate stomatal conductance Transpiration rate
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小麦叶片和冠层尺度气体交换模型关键参数的季节变化特征
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作者 赵福年 刘江 +4 位作者 张强 张良 王润元 王鹤龄 侯金亮 《气象科学》 2024年第1期166-175,共10页
本文从叶片和冠层尺度入手,采用手持式光合仪和涡动相关法,分析确定C3作物春小麦和冬小麦气体交换模型关键参数随季节变化的特征。结果表明:春小麦叶片尺度最大羧化速率和最大电子传递速率在生育末期快速减小,其他阶段差异不显著,但二... 本文从叶片和冠层尺度入手,采用手持式光合仪和涡动相关法,分析确定C3作物春小麦和冬小麦气体交换模型关键参数随季节变化的特征。结果表明:春小麦叶片尺度最大羧化速率和最大电子传递速率在生育末期快速减小,其他阶段差异不显著,但二者之比随发育期变化相对稳定,均值为2.2;春小麦生长季叶片气孔导度模型斜率在9~11间变动,均值为9.7。冬小麦冠层尺度最大羧化速率和最大电子传递速率随发育期呈抛物线变化,但二者之比相对稳定,均值为1.43;冬小麦冠层导度模型斜率在不同年份不同季节变化无明显规律,整个生育期围绕均值12波动。本研究论证了表征作物光合能力的参数随生育期变化以及气孔导度模型斜率相对稳定的特征。可为陆气相互作用过程分析以及生态系统碳—水循环模拟提供参数化依据。 展开更多
关键词 最大羧化速率 气孔导度模型斜率 小麦 碳—水交换 光合能力
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紫花苜蓿光合特性及抗氧化物质对冷适应的响应
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作者 孙万斌 马晖玲 周青平 《草原与草坪》 CAS CSCD 2024年第3期26-34,共9页
【目的】探究紫花苜蓿在冷适应过程中光合特性指标和抗氧化物质含量的变化。【方法】将10个紫花苜蓿品种的4周龄幼苗进行4℃冷适应处理,分别在第0、7、14天测定其叶绿素含量、渗透压、相对电导率、光合特性指标、活性氧物质和抗氧化物... 【目的】探究紫花苜蓿在冷适应过程中光合特性指标和抗氧化物质含量的变化。【方法】将10个紫花苜蓿品种的4周龄幼苗进行4℃冷适应处理,分别在第0、7、14天测定其叶绿素含量、渗透压、相对电导率、光合特性指标、活性氧物质和抗氧化物质含量。【结果】在冷适应初期(0~7 d),细胞膜受到损伤,造成离子泄露,叶片相对电导率升高,但随着冷适应过程的持续(7~14 d),离子泄露量减少,相对电导率降低,植株的抗寒性初步形成;冷适应造成叶绿素a、b含量、净光合速率、PSⅡ实际光化学效率及PSⅡ最大光化学效率降低。【结论】紫花苜蓿幼苗在冷适应过程中,其渗透压、抗坏血酸、氧化型谷胱甘肽和还原型谷胱甘肽含量持续升高,幼苗通过提高细胞液的渗透压,增加细胞液浓度,增强细胞的渗透调节能力,同时增加抗氧化物质含量,提高其抗氧化能力,从而减缓了超氧阴离子自由基和过氧化氢含量的持续升高。 展开更多
关键词 紫花苜蓿 冷适应 相对电导率 光合特性 抗氧化物质
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利用电石渣替代水泥开发固碳胶凝材料
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作者 许雪艳 贾英杰 《材料科学与工程学报》 CAS CSCD 北大核心 2024年第1期123-128,136,共7页
本研究利用电石渣替代部分水泥,制备新型固碳胶凝材料,研究了不同电石渣含量的胶凝材料对600 kg/m3等级泡沫混凝土的基础性能及固碳性能的影响。研究表明:电石渣的掺入导致泡沫混凝土气孔变大,28 d抗压强度先升高后降低,保温性能提高;... 本研究利用电石渣替代部分水泥,制备新型固碳胶凝材料,研究了不同电石渣含量的胶凝材料对600 kg/m3等级泡沫混凝土的基础性能及固碳性能的影响。研究表明:电石渣的掺入导致泡沫混凝土气孔变大,28 d抗压强度先升高后降低,保温性能提高;当电石渣取代10%水泥,制备出的泡沫混凝土干密度为595 kg/m3,28 d抗压强度比未掺加电石渣的提高4.2%,达5.0 MPa;当电石渣取代50%水泥,制备出的泡沫混凝土导热系数比未掺加电石渣的降低17.1%,为1.131 W·m-1·K-1。电石渣掺加有利于改善泡沫混凝土收缩,当电石渣掺量增加,泡沫混凝土先呈现收缩减小后出现膨胀。碳化养护不仅能够固化封存CO_(2),还能提高泡沫混凝土的力学性能与保温性能。电石渣掺量越高,泡沫混凝土固碳能力越强,电石渣掺量为50%时,CO_(2)的捕获量达到46.02 wt%。 展开更多
关键词 电石渣 固碳胶凝材料 泡沫混凝土 气孔结构 导热系数 力学性能
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