The switch from C-3 to CAM pathway was induced by water stress in a C-3/CAM intermediate plant Sedum spectabile Boreau. Typical CAM criteria were observed upon 15 d of withholding water. Leaf delta(13)C value (-%) and...The switch from C-3 to CAM pathway was induced by water stress in a C-3/CAM intermediate plant Sedum spectabile Boreau. Typical CAM criteria were observed upon 15 d of withholding water. Leaf delta(13)C value (-%) and water content showed a linear correlation fashion. Chlorophyll fluorescence parameters and antioxidative capacity were altered by water stress. Phi(PSII) and q(P) were reduced by 50% and 34% of the control, respectively, while NPQ rose ca. 180%. SOD activity and ability to scavenge DPPH. free radical went down but membrane permeability changed slightly. However, when an additional photooxidation by MV with high PPFD was carried out with leaf discs from watered (C-3 mode) and drought plants (CAM mode), q(P) and Phi(PSII) in leaves at induced CAM mode stage continuously decreased to a very low level. High 1 - q(P) value (0.86) and 1 - q(P)/NPQ ratio (>1) indicated the presence of high reduction state and unbalance of light energy budget. Together with the marked loss of membrane integral, it was evidenced that photooxidative damage was more serious in the induced CAM mode than in the C-3 mode. No advantage of photooxidation tolerance was found at the induced CAM expression stage of the facultative CAM plant, as compared with its C-3 mode stage, and also with the constitutive CAM plants reported previously. The differences in photooxidation sensitivity between the inducible CAM expressing plant and the constitutive CAM plant were discussed.展开更多
To research how planting Sedum spectabile affects Cd loss, in this experiment, the impact of soil pollution level (low, medium, high), rainfall intensity (30, 60, 90 mm·h<sup>-1</sup>), and slope ...To research how planting Sedum spectabile affects Cd loss, in this experiment, the impact of soil pollution level (low, medium, high), rainfall intensity (30, 60, 90 mm·h<sup>-1</sup>), and slope (6°, 12°, 18°, 24°) on Cd concentration in soil and runoff after planting Sedum spectabile are investigating using an indoor artificial rainfall simulation method. The results showed that: 1) The mean values of agricultural soils in the study area reached 38.52 and 1073.28 mg·kg<sup>-1</sup> for Cd and Zn, respectively, which were 176.70 and 11.96 times higher than the background values of soil environment in southern Yunnan. 2) The decrease of total Cd in the soil after planting Sedum spectabile ranged from 17.52% to 31.09%, and the decrease of effective state Cd ranged from 14.36% to 21.81%. The higher the pollution level, the more significant the decrease of effective state Cd. 3) After 120 days of planting, the Cd concentration in runoff decreased between 22.40% and 89.23% compared to 15 days, with the more significant decrease in low Cd pollution, 90 mm·h<sup>-1</sup> rainfall, medium Cd pollution, 30 mm·h<sup>-1</sup> rainfall, and high Cd pollution, 90 mm·h<sup>-1</sup>, reaching 81.14% - 87.43%, 82.21% - 89.00%, and 37.57% - 89.23%. 4) The pollution level and rainfall intensity were significantly and positively correlated with Cd concentration in runoff at 15 and 120 days of planting Sedum spectabile, with correlation coefficients of 0.498, 0.641, and 0.435, 0.464. Research shows that planting Sedum spectabile can reduce the Cd concentration in soil and runoff, which is essential for the remediation of Cd-contaminated farmland.展开更多
Water-soluble chitosan(WSC)has been studied for its ability to mobilize soil Pb and promote the phytoremediation by Hylotelephium spectabile in Pb-contaminated fields.We aimed to clarify the internal mechanism by whic...Water-soluble chitosan(WSC)has been studied for its ability to mobilize soil Pb and promote the phytoremediation by Hylotelephium spectabile in Pb-contaminated fields.We aimed to clarify the internal mechanism by which wSC impacts phytoremediation by examining plant growth and Pb accumulation performance of H.spectabile as well as the Pb form,functional groups,and mineral phases of Pb-contaminated soil.WSC effectively decreased soil pH and activated Pb migration in rhizosphere soils,with a considerable increase in water-soluble and acid-extractable Pb by 29%-102%and 9%-65%,respectively,and a clear decreasing trend in reducible and oxidizable Pb.Fourier-transform infrared spectroscopy revealed a significant increase in amino and hydroxyl groups in the soil generated by WSC.The coordination of Pb with amino and hydroxyl groups may play an important role in the formation of Pb complexes and activation of Pb in soil.In field trials,the application of WSC significantly increased Pb accumulation in H.spectabile by 125.44%,reaching 92 g/hm^(2).Moreover,the organic matter and nitrogen in the soils were increased by WSc,which improved the growth conditions of H.spectabile.No obvious growth inhibition was observed in either the pot or field trials.Therefore,WSC is a promising chelating agent for mobilizing Pb in soil.Additionally,WSC can be potentially used to boost H.spectabil-mediated phytoremediation of Pb-contaminatedfarmland.展开更多
This study investigates the accumulation characteristics and cost-benefit evaluation of the monoculture modes of Pteris vittata(MP)and Hylotelephium spectabile(MH),as well as their intercropping with peach(LP and LH)i...This study investigates the accumulation characteristics and cost-benefit evaluation of the monoculture modes of Pteris vittata(MP)and Hylotelephium spectabile(MH),as well as their intercropping with peach(LP and LH)in arsenic(As)-or cadmium(Cd)-contaminated orchards.The intercropping modes exhibited remediation efficiencies comparable to those of their respective monocultures.Soil As/Cd concentrations were projected to fall below risk intervention values in the 21st,22nd,34th,and 30th years for MP,LP,MH,and LH,respectively.The gross ecosystem product(GEP)of the intercropping modes significantly exceeded that of the corresponding monoculture,with peach profits contributing 85.8%-97.0%.The net present values(NPV)were achieved in 7 and 2 years for LP and LH,respectively.Furthermore,the economic viability of intercropping was primarily influenced by the economic benefits of peach and accumulator cultivation costs.These findings suggest that intercropping with peach provides economic benefits over monoculture in the management of As-or Cd-contaminated orchards.However,further optimization of seedling cost,disposal technologies,and mechanization of accumulator cultivation is required to enhance the feasibility.展开更多
文摘The switch from C-3 to CAM pathway was induced by water stress in a C-3/CAM intermediate plant Sedum spectabile Boreau. Typical CAM criteria were observed upon 15 d of withholding water. Leaf delta(13)C value (-%) and water content showed a linear correlation fashion. Chlorophyll fluorescence parameters and antioxidative capacity were altered by water stress. Phi(PSII) and q(P) were reduced by 50% and 34% of the control, respectively, while NPQ rose ca. 180%. SOD activity and ability to scavenge DPPH. free radical went down but membrane permeability changed slightly. However, when an additional photooxidation by MV with high PPFD was carried out with leaf discs from watered (C-3 mode) and drought plants (CAM mode), q(P) and Phi(PSII) in leaves at induced CAM mode stage continuously decreased to a very low level. High 1 - q(P) value (0.86) and 1 - q(P)/NPQ ratio (>1) indicated the presence of high reduction state and unbalance of light energy budget. Together with the marked loss of membrane integral, it was evidenced that photooxidative damage was more serious in the induced CAM mode than in the C-3 mode. No advantage of photooxidation tolerance was found at the induced CAM expression stage of the facultative CAM plant, as compared with its C-3 mode stage, and also with the constitutive CAM plants reported previously. The differences in photooxidation sensitivity between the inducible CAM expressing plant and the constitutive CAM plant were discussed.
文摘To research how planting Sedum spectabile affects Cd loss, in this experiment, the impact of soil pollution level (low, medium, high), rainfall intensity (30, 60, 90 mm·h<sup>-1</sup>), and slope (6°, 12°, 18°, 24°) on Cd concentration in soil and runoff after planting Sedum spectabile are investigating using an indoor artificial rainfall simulation method. The results showed that: 1) The mean values of agricultural soils in the study area reached 38.52 and 1073.28 mg·kg<sup>-1</sup> for Cd and Zn, respectively, which were 176.70 and 11.96 times higher than the background values of soil environment in southern Yunnan. 2) The decrease of total Cd in the soil after planting Sedum spectabile ranged from 17.52% to 31.09%, and the decrease of effective state Cd ranged from 14.36% to 21.81%. The higher the pollution level, the more significant the decrease of effective state Cd. 3) After 120 days of planting, the Cd concentration in runoff decreased between 22.40% and 89.23% compared to 15 days, with the more significant decrease in low Cd pollution, 90 mm·h<sup>-1</sup> rainfall, medium Cd pollution, 30 mm·h<sup>-1</sup> rainfall, and high Cd pollution, 90 mm·h<sup>-1</sup>, reaching 81.14% - 87.43%, 82.21% - 89.00%, and 37.57% - 89.23%. 4) The pollution level and rainfall intensity were significantly and positively correlated with Cd concentration in runoff at 15 and 120 days of planting Sedum spectabile, with correlation coefficients of 0.498, 0.641, and 0.435, 0.464. Research shows that planting Sedum spectabile can reduce the Cd concentration in soil and runoff, which is essential for the remediation of Cd-contaminated farmland.
基金The research was financially supported by the National Natural Science Foundation of China(Nos.42277237,22206149,and 41907125)the Applied Basic Research Project of Shanxi Province(China)(No.20210302124220)the Horizontal Scientific Research Funds of Taiyuan University of Technology(Nos.RH2200002532 and RH2300002821).
文摘Water-soluble chitosan(WSC)has been studied for its ability to mobilize soil Pb and promote the phytoremediation by Hylotelephium spectabile in Pb-contaminated fields.We aimed to clarify the internal mechanism by which wSC impacts phytoremediation by examining plant growth and Pb accumulation performance of H.spectabile as well as the Pb form,functional groups,and mineral phases of Pb-contaminated soil.WSC effectively decreased soil pH and activated Pb migration in rhizosphere soils,with a considerable increase in water-soluble and acid-extractable Pb by 29%-102%and 9%-65%,respectively,and a clear decreasing trend in reducible and oxidizable Pb.Fourier-transform infrared spectroscopy revealed a significant increase in amino and hydroxyl groups in the soil generated by WSC.The coordination of Pb with amino and hydroxyl groups may play an important role in the formation of Pb complexes and activation of Pb in soil.In field trials,the application of WSC significantly increased Pb accumulation in H.spectabile by 125.44%,reaching 92 g/hm^(2).Moreover,the organic matter and nitrogen in the soils were increased by WSc,which improved the growth conditions of H.spectabile.No obvious growth inhibition was observed in either the pot or field trials.Therefore,WSC is a promising chelating agent for mobilizing Pb in soil.Additionally,WSC can be potentially used to boost H.spectabil-mediated phytoremediation of Pb-contaminatedfarmland.
基金support from National Natural Science Foundation of China(Grant Nos.42277237,41907125).
文摘This study investigates the accumulation characteristics and cost-benefit evaluation of the monoculture modes of Pteris vittata(MP)and Hylotelephium spectabile(MH),as well as their intercropping with peach(LP and LH)in arsenic(As)-or cadmium(Cd)-contaminated orchards.The intercropping modes exhibited remediation efficiencies comparable to those of their respective monocultures.Soil As/Cd concentrations were projected to fall below risk intervention values in the 21st,22nd,34th,and 30th years for MP,LP,MH,and LH,respectively.The gross ecosystem product(GEP)of the intercropping modes significantly exceeded that of the corresponding monoculture,with peach profits contributing 85.8%-97.0%.The net present values(NPV)were achieved in 7 and 2 years for LP and LH,respectively.Furthermore,the economic viability of intercropping was primarily influenced by the economic benefits of peach and accumulator cultivation costs.These findings suggest that intercropping with peach provides economic benefits over monoculture in the management of As-or Cd-contaminated orchards.However,further optimization of seedling cost,disposal technologies,and mechanization of accumulator cultivation is required to enhance the feasibility.
