As a key functional trait affecting many physiological processes,leaf pH is closely related to other leaf traits at the local scale.Nevertheless,whether and how leaf pH is linked with other leaf functional traits acro...As a key functional trait affecting many physiological processes,leaf pH is closely related to other leaf traits at the local scale.Nevertheless,whether and how leaf pH is linked with other leaf functional traits across geographic scales remains unclear.A field survey in northern China was conducted to investigate the relationships between leaf pH and some key leaf structural(specific leaf area,SLA;leaf dry matter content,LDMC)and chemical traits(elemental concentrations;total dissolved solids,TDS;practical salinity),as well as the effects of environmental factors on these relationships.Our results showed that the trait coordination may vary in degree or direction across eco-geographic regions(arid vs.non-arid regions)and life-forms(woody vs.herbaceous plants).Generally,leaf pH was negatively related to SLA,but positively related to TDS and salinity.However,leaf pH and LDMC were negatively correlated in arid regions but positively correlated in non-arid regions;leaf pH covaried with N(similarly,with Ca,Mg and Na)in the same direction for both herbaceous and woody plants in arid regions,but not in non-arid regions.Climatic factors mainly influenced the relationships of leaf pH with leaf Ca and Fe concentrations,while soil factors mostly affected those with leaf P,Ca and Mn concentrations.Our findings highlight the divergent coordination between leaf pH and other leaf traits across life-forms and eco-geographic regions and may shed light on the in-depth understanding of the role of acid-base balance in plant eco-physiological processes and ecological adaptation over biogeographic scales.展开更多
A rhizobox experiment was conducted to compare iron （Fe） oxidation and changes of pH, redox potential （Eh） and fractions of zinc （Zn） and lead （Pb） in rhizosphere and non-rhizosphere soils of four emergent-roo...A rhizobox experiment was conducted to compare iron （Fe） oxidation and changes of pH, redox potential （Eh） and fractions of zinc （Zn） and lead （Pb） in rhizosphere and non-rhizosphere soils of four emergent-rooted wetland plants （Echinodorus macrophyllus, Eleocharis geniculata, Hydrocotyle vulgaris and Veronica serpyllifolia） with different radial oxygen loss （ROL） from roots. The results indicated that all these wetland plants decreased pH and concentration of Fe（II） but increased the Eh in the rhizosphere soils. Pb and Zn were transformed from unstable fractions to more stable fractions in the rhizosphere soils, so decreasing their potential metal mobility factors （MF）. Among the four plants, E. macrophyllus, with the highest ROL and root biomass, possessed the greatest ability in formation of Fe plaque and in the reduction of heavy metal MFs in the rhizosphere soil. Wetland plants, with higher ROLs and root biomass, may thus be effective in decreasing potential long-term heavy metal bioavailabilities.展开更多
To compare current methods of pretreatment/determination for plant foliar pH,we proposed a method for longperiod sample preservation with little interference with the stability of foliar pH.Four hundred leaf samples f...To compare current methods of pretreatment/determination for plant foliar pH,we proposed a method for longperiod sample preservation with little interference with the stability of foliar pH.Four hundred leaf samples from 20 species were collected and four methods of pH determination were used:refrigerated(stored at 4°C for 4 days),frozen(stored at−16°C for 4 days),oven-dried and fresh green-leaf pH(control).To explore the effects of different leaf:water mixing ratio on the pH determination results,we measured oven-dried green-leaf pH by leaf:water volume ratio of 1:8 and mass ratio of 1:10,and measured frozen senesced-leaf pH by mass ratio of 1:10 and 1:15.The standard major axis regression was used to analyze the relationship and the conversion equation between the measured pH with different methods.Foliar pH of refrigerated and frozen green leaves did not signifcantly differ from that of fresh green-leaf,but drying always overrated fresh green-leaf pH.During the feld sampling,cryopreservation with a portable refrigerator was an advisable choice to get a precise pH.For long-duration feld sampling,freezing was the optimal choice,and refrigeration is the best choice for the shorttime preservation.The different leaf:water mixing ratio signifcantly infuenced the measured foliar pH.High dilution reduced the proton concentration and increased the measured pH.Our fndings provide the conversion relationships between the existing pretreatment and measurement methods,and establish a connection among pH determined by different methods.Our study can facilitate foliar pH measurement,thus contributing to understanding of this interesting plant functional trait.展开更多
The potential role of soil pH in modulating plant productivity was assessed on the basis of dry mass, harvested in the form of 0.25 m2 quadrats, in two low-productivity upland grasslands of northern Greece subjected t...The potential role of soil pH in modulating plant productivity was assessed on the basis of dry mass, harvested in the form of 0.25 m2 quadrats, in two low-productivity upland grasslands of northern Greece subjected to annual factorial nitrogen （N） and phosphorus （P） fertilization （15 g N m-2 year-1 and 10 g P m-2 year-I） over a minimum period of 3 years. It was hypothesized that under these particular conditions, a positive relationship would exist between soil pH and plant productivity and, further, that N or P fertilizer application of a nutrient limited system, would result in a weakening of this positive relationship. A significant positive relationship was confirmed between soil pH and plant productivity in one of the two study areas and a positive trend in the other. Moreover, plant productivity increase, following fertilization, appeared to have a detrimental effect on the soil pH-plant productivity relationship. Findings support the original hypotheses and strengthen the idea that plant diversity-mediated soil pH-plant productivity relationships are a result of the more intense plant speciation that occurred under the more ＂typical＂ soil conditions of higher pH in temperate as opposed to tropical regions展开更多
Arsenic （As） contamination has become the environment issue of global concern. In China, large area of farmland and the site soil were contaminated by As, which means that suitable remedying methods were urgently ne...Arsenic （As） contamination has become the environment issue of global concern. In China, large area of farmland and the site soil were contaminated by As, which means that suitable remedying methods were urgently needed. Phytoremediation, as one of environment-friendly soil remediation techniques developed in recent years, shows a bright future for the remediation of As contaminated soils. However, phytoremediation efficiency needs to be enhanced further because of low concentration of bio- available As in the soils. A triangle flask culture experiment was carried out to study the effects of functional species, isolated from As-polluted soils, that could improve As mobility from the soil. These species included two bacilli, B 1 and B2 （Breviba- cillus） and two fungi, F1 （Trichoderma）, F2 （Fusarium）. They could transform the concentration of As fractionation in the soil sterilized by the method of 6~Co-T ray. Through the experiment, the concentrations of non-specifically-sorbed and specifical- ly-sorbed As fractionation, and pH value of culture solution with inoculated treatment were higher than that with the control. Especially, the concentration of non-specifically-sorbed As fractionation in the treatment-inoculated species was 2 to 6 times higher than that of non-inoculation treatment. Moreover, two bacilli and two fungi could produce IAA, which was conducive to the plant survival when they were jointly used in remedying the As-contaminated soil.展开更多
基金supported by the National Natural Science Foundation of China(32001165,41473068)the Natural Science Foundation of Sichuan Province(2022NSFSC1753)+1 种基金the Strategic Priority Research Program of the Chinese Academy of Sciences(XDA26040202)the Free Exploration Project of the Dual Support Plan for Disciplinary Development of Sichuan Agricultural University(2024ZYTS016).
文摘As a key functional trait affecting many physiological processes,leaf pH is closely related to other leaf traits at the local scale.Nevertheless,whether and how leaf pH is linked with other leaf functional traits across geographic scales remains unclear.A field survey in northern China was conducted to investigate the relationships between leaf pH and some key leaf structural(specific leaf area,SLA;leaf dry matter content,LDMC)and chemical traits(elemental concentrations;total dissolved solids,TDS;practical salinity),as well as the effects of environmental factors on these relationships.Our results showed that the trait coordination may vary in degree or direction across eco-geographic regions(arid vs.non-arid regions)and life-forms(woody vs.herbaceous plants).Generally,leaf pH was negatively related to SLA,but positively related to TDS and salinity.However,leaf pH and LDMC were negatively correlated in arid regions but positively correlated in non-arid regions;leaf pH covaried with N(similarly,with Ca,Mg and Na)in the same direction for both herbaceous and woody plants in arid regions,but not in non-arid regions.Climatic factors mainly influenced the relationships of leaf pH with leaf Ca and Fe concentrations,while soil factors mostly affected those with leaf P,Ca and Mn concentrations.Our findings highlight the divergent coordination between leaf pH and other leaf traits across life-forms and eco-geographic regions and may shed light on the in-depth understanding of the role of acid-base balance in plant eco-physiological processes and ecological adaptation over biogeographic scales.
基金Supported by the National Natural Science Foundation of China(No.30570345)the NSFC-Guangdong Joint Fund,China(No.U0833004)+1 种基金the Specialized Research Fund for the Doctoral Program of Higher Education of China(No.20558097)the Fundamental Research Funds for the Central Universities of China(No.10lgzd10)
文摘A rhizobox experiment was conducted to compare iron （Fe） oxidation and changes of pH, redox potential （Eh） and fractions of zinc （Zn） and lead （Pb） in rhizosphere and non-rhizosphere soils of four emergent-rooted wetland plants （Echinodorus macrophyllus, Eleocharis geniculata, Hydrocotyle vulgaris and Veronica serpyllifolia） with different radial oxygen loss （ROL） from roots. The results indicated that all these wetland plants decreased pH and concentration of Fe（II） but increased the Eh in the rhizosphere soils. Pb and Zn were transformed from unstable fractions to more stable fractions in the rhizosphere soils, so decreasing their potential metal mobility factors （MF）. Among the four plants, E. macrophyllus, with the highest ROL and root biomass, possessed the greatest ability in formation of Fe plaque and in the reduction of heavy metal MFs in the rhizosphere soil. Wetland plants, with higher ROLs and root biomass, may thus be effective in decreasing potential long-term heavy metal bioavailabilities.
基金supported by the‘Strategic Priority Research Program’of the Chinese Academy of Sciences(XDA26040202)the National Natural Science Foundation of China(32001165)supported by Chinese Universities Scientifc Fund(2021TC117).
文摘To compare current methods of pretreatment/determination for plant foliar pH,we proposed a method for longperiod sample preservation with little interference with the stability of foliar pH.Four hundred leaf samples from 20 species were collected and four methods of pH determination were used:refrigerated(stored at 4°C for 4 days),frozen(stored at−16°C for 4 days),oven-dried and fresh green-leaf pH(control).To explore the effects of different leaf:water mixing ratio on the pH determination results,we measured oven-dried green-leaf pH by leaf:water volume ratio of 1:8 and mass ratio of 1:10,and measured frozen senesced-leaf pH by mass ratio of 1:10 and 1:15.The standard major axis regression was used to analyze the relationship and the conversion equation between the measured pH with different methods.Foliar pH of refrigerated and frozen green leaves did not signifcantly differ from that of fresh green-leaf,but drying always overrated fresh green-leaf pH.During the feld sampling,cryopreservation with a portable refrigerator was an advisable choice to get a precise pH.For long-duration feld sampling,freezing was the optimal choice,and refrigeration is the best choice for the shorttime preservation.The different leaf:water mixing ratio signifcantly infuenced the measured foliar pH.High dilution reduced the proton concentration and increased the measured pH.Our fndings provide the conversion relationships between the existing pretreatment and measurement methods,and establish a connection among pH determined by different methods.Our study can facilitate foliar pH measurement,thus contributing to understanding of this interesting plant functional trait.
基金Supported by the Greek National Scholarship Foundation
文摘The potential role of soil pH in modulating plant productivity was assessed on the basis of dry mass, harvested in the form of 0.25 m2 quadrats, in two low-productivity upland grasslands of northern Greece subjected to annual factorial nitrogen （N） and phosphorus （P） fertilization （15 g N m-2 year-1 and 10 g P m-2 year-I） over a minimum period of 3 years. It was hypothesized that under these particular conditions, a positive relationship would exist between soil pH and plant productivity and, further, that N or P fertilizer application of a nutrient limited system, would result in a weakening of this positive relationship. A significant positive relationship was confirmed between soil pH and plant productivity in one of the two study areas and a positive trend in the other. Moreover, plant productivity increase, following fertilization, appeared to have a detrimental effect on the soil pH-plant productivity relationship. Findings support the original hypotheses and strengthen the idea that plant diversity-mediated soil pH-plant productivity relationships are a result of the more intense plant speciation that occurred under the more ＂typical＂ soil conditions of higher pH in temperate as opposed to tropical regions
基金supported by the National Natural Science Foundation of China (Grant Nos. 21307080 and 41101232)Shanghai Knowledge Service Platform (Grant No. ZF1224)Key Discipline Construction Projects of Shanghai Second Polytechnic University (Grant No. XXKYS1404)
文摘Arsenic （As） contamination has become the environment issue of global concern. In China, large area of farmland and the site soil were contaminated by As, which means that suitable remedying methods were urgently needed. Phytoremediation, as one of environment-friendly soil remediation techniques developed in recent years, shows a bright future for the remediation of As contaminated soils. However, phytoremediation efficiency needs to be enhanced further because of low concentration of bio- available As in the soils. A triangle flask culture experiment was carried out to study the effects of functional species, isolated from As-polluted soils, that could improve As mobility from the soil. These species included two bacilli, B 1 and B2 （Breviba- cillus） and two fungi, F1 （Trichoderma）, F2 （Fusarium）. They could transform the concentration of As fractionation in the soil sterilized by the method of 6~Co-T ray. Through the experiment, the concentrations of non-specifically-sorbed and specifical- ly-sorbed As fractionation, and pH value of culture solution with inoculated treatment were higher than that with the control. Especially, the concentration of non-specifically-sorbed As fractionation in the treatment-inoculated species was 2 to 6 times higher than that of non-inoculation treatment. Moreover, two bacilli and two fungi could produce IAA, which was conducive to the plant survival when they were jointly used in remedying the As-contaminated soil.
