Here,we report the mechanical and water sorption properties of a green composite based on Typha latifolia fibres.The composite was prepared either completely binder-less or bonded with 10%(w/w)of a bio-based resin whi...Here,we report the mechanical and water sorption properties of a green composite based on Typha latifolia fibres.The composite was prepared either completely binder-less or bonded with 10%(w/w)of a bio-based resin which was a mixture of an epoxidized linseed oil and a tall-oil based polyamide.The flexural modulus of elasticity,the flexural strength and the water absorption of hot pressed Typha panels were measured and the influence of pressing time and panel density on these properties was investigated.The cure kinetics of the biobased resin was analyzed by differential scanning calorimetry(DSC)in combination with the iso-conversional kinetic analysis method of Vyazovkin to derive the curing conditions required for achieving completely cured resin.For the binderless Typha panels the best technological properties were achieved for panels with high density.By adding 10%of the binder resin the flexural strength and especially the water absorption were improved significantly.展开更多
The aim of this study was to determine the species composition, biodiversity and, relative abundance of epiphytic algae and their relationship with environmental variables on Typha latifolia and Phragmites australis a...The aim of this study was to determine the species composition, biodiversity and, relative abundance of epiphytic algae and their relationship with environmental variables on Typha latifolia and Phragmites australis at Lake Gala(National Park). Epiphytic algae were gathered monthly by collecting aquatic plants between March 2014 and November 2014. In the epiphytic flora were a total of 133 taxa were identified, 107 taxa were identified on T. latifolia and 96 were discovered on P. australis. While the mean species richness, species diversity and evenness values of the algae identified on T. latifolia were 46, 1.85 and 0.51 respectively, these values were respectively 43, 1.51 and 0.43 on P. australis. While diatoms were generally dominant, other dominant groups in the epiphytic flora included green algae and blue-green algae. The algae that had the highest relative biovolume on T. latifolia were Spirogyra affinis, Oscillatoria sancta and Gomphonema acuminatum, while the algae that had the highest relative biovolume on P. australis were E pithemia adnata, Oscillatoria sancta and R hopalodia gibba. Results show that species composition of epiphytic algae was different, but diversity values were similar on all the macrophytes. The hydrological pulse is one of the most important factors determining the physical and chemical environment of the epiphytic algal community. It was found that some environmental factors were highly eff ective on community distribution in the epiphyton. Additionally, it was observed that some epiphytic algae species had a substrate preference between T. latifolia and P. australis.展开更多
The effects of foliar spraying with spermidine (Spd), ranging in concentration from 0.25 to 0.50 mmol/L, on the antioxidant system under Cd2+ stress (range 0.1–0.2 mmol/L Cd2+) in Typha latifolia L. grown hydroponica...The effects of foliar spraying with spermidine (Spd), ranging in concentration from 0.25 to 0.50 mmol/L, on the antioxidant system under Cd2+ stress (range 0.1–0.2 mmol/L Cd2+) in Typha latifolia L. grown hydroponically were investigated in order to offer a referenced evidence for an understanding of the mechanism by which polyamines (PAs) relieve the damage to plants by heavy metal and improve the phytoremediation efficiency of heavy metal-contaminated water. The results showed that Cd2+ stress induced oxidative injury, as evidenced by an increase in the generation of superoxide anion (O2-), as well as the hydrogen peroxide (H2O2) and malondialdehyde (MDA) contents in both leaves and caudices. With the exception of superoxide dismutase (SOD) activity in the leaves, an increase in the activities of catalase (CAT), guaiacol peroxidase (GPX), and glutathione reductase (GR) was observed in both leaves and caudices, SOD activity was increased in caudices, and ascorbate peroxidase (APX) activity was increased in leaves following Cd2+ treatment. The reduced glutathione (GSH) content in both leaves and caudices and the reductive ascorbate content in leaves was obviously increased, which were prompted by the application of exogenous Spd. Spraying with Spd increased the activity of GR and APX in both leaves and caudices, whereas the activity of SOD, CAT, and GPX was increased only in caudices following spraying with Spd. The generation of O2 -. and the H2O2 and MDA content in both leaves and caudices decreased after spraying with Spd. The decrease in MDA was more obvious following the application of 0.25 than 0.50 mmol/L Spd. It is supposed that exogenous Spd elevated the tolerance of T. latifolia under Cd2+ stress primarily by increasing GR activity and the GSH level.展开更多
Liberty State Park in New Jersey,USA,is a ＂brownfield＂ site containing various levels of contaminants.To investigate metal uptake and distributions in plants on the brownfield site,Phragmites australis and Typha lat...Liberty State Park in New Jersey,USA,is a ＂brownfield＂ site containing various levels of contaminants.To investigate metal uptake and distributions in plants on the brownfield site,Phragmites australis and Typha latifolia were collected in Liberty State Park during the growing season（May–September）in 2011 at two sites with the high and low metal loads,respectively.The objective of this study was to understand the metal（Fe,Mn,Cu,Pb and Zn）concentration and spatial distributions in P.australis and T.latifolia root systems with micro-meter scale resolution using synchrotron X-ray microfluorescence（μXRF）and synchrotron X-ray computed microtomography（μCMT）techniques.The root structure measurement by synchrotron μCMT showed that high X-ray attenuation substance appeared in the epidermis.Synchrotron μXRF measurement showed that metal concentrations and distributions in the root cross-section between epidermis and vascular tissue were statistically different.Significant correlations were found between metals（Cu,Mn,Pb and Zn）and Fe in the epidermis,implying that metals were scavenged by Fe oxides.The results from this study suggest that the expression of metal transport and accumulation within the root systems may be element specific.The information derived from this study can improve our current knowledge of the wetland plant ecological function in brownfield remediation.展开更多
The uptake of metals in roots and their transfer to rhizomes and above-ground plant parts（stems, leaves） of cattails（Typha latifolia L.） were studied in leachates from a domestic landfill site（Etueffont, France）...The uptake of metals in roots and their transfer to rhizomes and above-ground plant parts（stems, leaves） of cattails（Typha latifolia L.） were studied in leachates from a domestic landfill site（Etueffont, France） and treated in a natural lagooning system. Plant parts and corresponding water and sediment samples were taken at the inflow and outflow points of the four ponds at the beginning and at the end of the growing season. Concentrations of As, Cd, Cr, Cu, Fe, Mn, Ni and Zn in the different compartments were estimated and their removal efficiency assessed, reaching more than 90% for Fe, Mn and Ni in spring and fall as well in the water compartment. The above-and below-ground cattail biomass varied from 0.21 to 0.85, and 0.34 to 1.24 kg dry weight/m^2, respectively, the highest values being recorded in the fourth pond in spring 2011. The root system was the first site of accumulation before the rhizome, stem and leaves. The highest metal concentration was observed in roots from cattails growing at the inflow of the system＇s first pond. The trend in the average trace element concentrations in the cattail plant organs can generally be expressed as： Fe 〉 Mn 〉 As 〉 Zn 〉 Cr 〉 Cu 〉 Ni 〉 Cd for both spring and fall. While T. latifolia removes trace elements efficiently from landfill leachates, attention should also be paid to the negative effects of these elements on plant growth.展开更多
基金funding and support from the Austrian Research Promotion Agency(FFG).
文摘Here,we report the mechanical and water sorption properties of a green composite based on Typha latifolia fibres.The composite was prepared either completely binder-less or bonded with 10%(w/w)of a bio-based resin which was a mixture of an epoxidized linseed oil and a tall-oil based polyamide.The flexural modulus of elasticity,the flexural strength and the water absorption of hot pressed Typha panels were measured and the influence of pressing time and panel density on these properties was investigated.The cure kinetics of the biobased resin was analyzed by differential scanning calorimetry(DSC)in combination with the iso-conversional kinetic analysis method of Vyazovkin to derive the curing conditions required for achieving completely cured resin.For the binderless Typha panels the best technological properties were achieved for panels with high density.By adding 10%of the binder resin the flexural strength and especially the water absorption were improved significantly.
文摘The aim of this study was to determine the species composition, biodiversity and, relative abundance of epiphytic algae and their relationship with environmental variables on Typha latifolia and Phragmites australis at Lake Gala(National Park). Epiphytic algae were gathered monthly by collecting aquatic plants between March 2014 and November 2014. In the epiphytic flora were a total of 133 taxa were identified, 107 taxa were identified on T. latifolia and 96 were discovered on P. australis. While the mean species richness, species diversity and evenness values of the algae identified on T. latifolia were 46, 1.85 and 0.51 respectively, these values were respectively 43, 1.51 and 0.43 on P. australis. While diatoms were generally dominant, other dominant groups in the epiphytic flora included green algae and blue-green algae. The algae that had the highest relative biovolume on T. latifolia were Spirogyra affinis, Oscillatoria sancta and Gomphonema acuminatum, while the algae that had the highest relative biovolume on P. australis were E pithemia adnata, Oscillatoria sancta and R hopalodia gibba. Results show that species composition of epiphytic algae was different, but diversity values were similar on all the macrophytes. The hydrological pulse is one of the most important factors determining the physical and chemical environment of the epiphytic algal community. It was found that some environmental factors were highly eff ective on community distribution in the epiphyton. Additionally, it was observed that some epiphytic algae species had a substrate preference between T. latifolia and P. australis.
文摘The effects of foliar spraying with spermidine (Spd), ranging in concentration from 0.25 to 0.50 mmol/L, on the antioxidant system under Cd2+ stress (range 0.1–0.2 mmol/L Cd2+) in Typha latifolia L. grown hydroponically were investigated in order to offer a referenced evidence for an understanding of the mechanism by which polyamines (PAs) relieve the damage to plants by heavy metal and improve the phytoremediation efficiency of heavy metal-contaminated water. The results showed that Cd2+ stress induced oxidative injury, as evidenced by an increase in the generation of superoxide anion (O2-), as well as the hydrogen peroxide (H2O2) and malondialdehyde (MDA) contents in both leaves and caudices. With the exception of superoxide dismutase (SOD) activity in the leaves, an increase in the activities of catalase (CAT), guaiacol peroxidase (GPX), and glutathione reductase (GR) was observed in both leaves and caudices, SOD activity was increased in caudices, and ascorbate peroxidase (APX) activity was increased in leaves following Cd2+ treatment. The reduced glutathione (GSH) content in both leaves and caudices and the reductive ascorbate content in leaves was obviously increased, which were prompted by the application of exogenous Spd. Spraying with Spd increased the activity of GR and APX in both leaves and caudices, whereas the activity of SOD, CAT, and GPX was increased only in caudices following spraying with Spd. The generation of O2 -. and the H2O2 and MDA content in both leaves and caudices decreased after spraying with Spd. The decrease in MDA was more obvious following the application of 0.25 than 0.50 mmol/L Spd. It is supposed that exogenous Spd elevated the tolerance of T. latifolia under Cd2+ stress primarily by increasing GR activity and the GSH level.
基金supported in part by the Margaret and Herman Sokol Foundation(HF)China Scholarship Council(YQ)+6 种基金the State Key Laboratory of Estuarine and Coastal Research Open Research Fund(Ref #:SKLEC-KF201304)(HF,WZ,LY,YQ)supported in part by the U.S.Department of Energy,Office of Science,Office of Workforce Development for Teachers and Scientists(WDTS)under the Visiting Faculty Program(VFP)(HF)Portions of this work were performed at Beamline X27A,National Synchrotron Light Source(NSLS),and Biosciences Department,Brookhaven National LaboratoryWork in Bioscience Department,BNL,was partially supported by the Division of Chemical Sciences,Geosciences,and Biosciences,Office of Basic Energy Sciences of the US Department of Energy through Grant DEAC0298CH10886the National Science Foundation through grant MCB-1051675(CJL)X27A is supported in part by the U.S.Department of Energy--Geosciences(DE-FG02-92ER14244 to The University of Chicago-CARS)Use of the NSLS was supported by the U.S.Department of Energy,Office of Science,Office of Basic Energy Sciences,under Contract No.DE-AC02-98CH10886
文摘Liberty State Park in New Jersey,USA,is a ＂brownfield＂ site containing various levels of contaminants.To investigate metal uptake and distributions in plants on the brownfield site,Phragmites australis and Typha latifolia were collected in Liberty State Park during the growing season（May–September）in 2011 at two sites with the high and low metal loads,respectively.The objective of this study was to understand the metal（Fe,Mn,Cu,Pb and Zn）concentration and spatial distributions in P.australis and T.latifolia root systems with micro-meter scale resolution using synchrotron X-ray microfluorescence（μXRF）and synchrotron X-ray computed microtomography（μCMT）techniques.The root structure measurement by synchrotron μCMT showed that high X-ray attenuation substance appeared in the epidermis.Synchrotron μXRF measurement showed that metal concentrations and distributions in the root cross-section between epidermis and vascular tissue were statistically different.Significant correlations were found between metals（Cu,Mn,Pb and Zn）and Fe in the epidermis,implying that metals were scavenged by Fe oxides.The results from this study suggest that the expression of metal transport and accumulation within the root systems may be element specific.The information derived from this study can improve our current knowledge of the wetland plant ecological function in brownfield remediation.
基金the SICTOM(Solid Waste Management Service) of Etueffont(Territoire de Belfort,France) for their financial help
文摘The uptake of metals in roots and their transfer to rhizomes and above-ground plant parts（stems, leaves） of cattails（Typha latifolia L.） were studied in leachates from a domestic landfill site（Etueffont, France） and treated in a natural lagooning system. Plant parts and corresponding water and sediment samples were taken at the inflow and outflow points of the four ponds at the beginning and at the end of the growing season. Concentrations of As, Cd, Cr, Cu, Fe, Mn, Ni and Zn in the different compartments were estimated and their removal efficiency assessed, reaching more than 90% for Fe, Mn and Ni in spring and fall as well in the water compartment. The above-and below-ground cattail biomass varied from 0.21 to 0.85, and 0.34 to 1.24 kg dry weight/m^2, respectively, the highest values being recorded in the fourth pond in spring 2011. The root system was the first site of accumulation before the rhizome, stem and leaves. The highest metal concentration was observed in roots from cattails growing at the inflow of the system＇s first pond. The trend in the average trace element concentrations in the cattail plant organs can generally be expressed as： Fe 〉 Mn 〉 As 〉 Zn 〉 Cr 〉 Cu 〉 Ni 〉 Cd for both spring and fall. While T. latifolia removes trace elements efficiently from landfill leachates, attention should also be paid to the negative effects of these elements on plant growth.
