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Effects of long-term ambient ozone exposure on biomass and wood traits in poplar treated with ethylenediurea (EDU)
2015
Carriero, G. | Emiliani, G. | Giovannelli, A. | Hoshika, Y. | Manning, W.J. | Traversi, M.L. | Paoletti, E.
This is the longest continuous experiment where ethylenediurea (EDU) was used to protect plants from ozone (O3). Effects of long-term ambient O3 exposure (23 ppm h AOT40) on biomass of an O3 sensitive poplar clone (Oxford) were examined after six years from in-ground planting. Trees were irrigated with either water or 450 ppm EDU. Above (−51%) and below-ground biomass (−47%) was reduced by O3 although the effect was significant only for stem and coarse roots. Ambient O3 decreased diameter of the lower stem, and increased moisture content along the stem of not-protected plants (+16%). No other change in the physical wood structure was observed. A comparison with a previous assessment in the same experiment suggested that O3 effects on biomass partitioning to above-ground organs depend on the tree ontogenetic stage. The root/shoot ratios did not change, suggesting that previous short-term observations of reduced allocation to tree roots may be overestimated.
显示更多 [+] 显示较少 [-]Tree rings reveal the reduction of Cd, Cu, Ni and Pb pollution in the central region of São Paulo, Brazil
2018
Locosselli, Giuliano Maselli | Chacón-Madrid, Katherine | Arruda, Marco Aurélio Zezzi | Pereira de Camargo, Evelyn | Lopes Moreira, Tiana Carla | Saldiva de André, Carmen Diva | André, Paulo Afonso de | Singer, Julio M. | Saldiva, Paulo H. N. (Paulo Hilário Nascimento) | Buckeridge, Marcos Silveira
The concern about environmental pollution has risen in the last decades because of its effects on human's health. However, evaluation of the exposure to certain pollutants is currently hampered by the availability of past environmental data. Tree rings are an alternative to reconstruct environmental variability of pre-instrumental periods. Nevertheless, this approach has some reported limitations including migration of chemical elements in the tree rings. The aim of this study was to evaluate the distribution of Cd, Cu, Hg, Na, Ni, Pb, Zn in the tree rings of Tipuana tipu (Fabaceae) to aid the reconstruction of past environmental pollution. We sampled trees in the central region of the city of São Paulo, Brazil, and scanned their tree rings using LA-ICP-MS. We used these data to evaluate the temporal trends of chemical elements under investigation. Results show a non-random distribution of these chemical elements within the tree rings, with higher content in the cell-walls of vessels and lower content in the fibers. Sodium was the only element intimately related to the axial parenchyma cells. Due to differences in elemental composition of xylem cells, temporal trends where evaluated using distinct quartiles of data distribution in each tree ring. The first quartile represents the lower content found in fibers and parenchyma, while the third quartile corresponds to the higher content found in vessels. Data from vessels better represent the decreasing trend of Cd, Cu, Pb, and Ni in the last three decades. This reduction is less significant for Na and Zn. Our results highlight the potential to improve the records of environmental pollution using data from different cells. Pronounced reduction in Pb may be attributed to the lead phase-out in gasoline, while the decreasing trend of Cd, Cu, Ni pollution is probably related to increasing efficiency of vehicles and the deindustrialization of São Paulo.Chemical elements are non-randomly distributed in tree rings. Chemical content of vessels cell-walls is a reliable record of metal pollution, which is decreasing in São Paulo.
显示更多 [+] 显示较少 [-][Tree conservation measures from the view of wood biology]
1988
Liese, W. (Hamburg Univ. (Germany, F.R.). Ordinariat fuer Holzbiologie)
Kinetics and Thermodynamics of Sorption for As(V) on the Porous Biomorph-Genetic Composite of α-Fe2O3/Fe3O4/C with Eucalyptus Wood Hierarchical Microstructure
2013
Zhu, Yinian | Zhu, Zongqiang | Chen, Yudao | Yang, Feng | Qin, Hui | Xie, Liwei
A novel porous biomorph-genetic composite of α-Fe₂O₃/Fe₃O₄/C (PBGC-Fe/C) with eucalyptus wood template was prepared, characterized and tested for its sorption capacity of As(V) from aqueous solution. The result indicated that the PBGC-Fe/C material retained the hierarchical porous structure of eucalyptus wood with three different types of pores (widths 70∼120, 4.1∼6.4 and 0.1∼1.3 μm) originating from vessels, fibres and pits of the wood, respectively. Its surface area was measured to be 59.2 m²/g. With increasing initial As(V) concentration from 5 to 100 mg/L, the amounts of As(V) sorbed on the pulverized PBGC-Fe/C sorbent (<0.149 mm) increased from 0.50 to 4.01 mg/g at 25 °C, from 0.50 to 4.83 mg/g at 35 °C and from 0.50 to 4.19 mg/g at 45 °C, and the corresponding removal rates decreased from 99.97 to 40.10 % at 25 °C, 99.95 to 48.40 % at 35 °C and 99.92 to 42.05 % at 45 °C. At the initial concentrations of 5, 10 and 50 mg/L, the sorption capacities for the unpulverized PBGC-Fe/C sorbent (>3 mm) were determined to be 0.50, 0.99 and 2.49 mg/g, respectively, which exhibited a similar average value to those of fine particles or nanoparticles of iron oxides. The sorption could well be described by the pseudo-second-order kinetic equation. The equilibrium data were found to follow Freundlich as well as Langmuir isotherms.
显示更多 [+] 显示较少 [-]Tritium based investigations into the water transport and water turnovers in spruce trees
1986
Strack, S. (Kernforschungszentrum Karlsruhe G.m.b.H. (Germany, F.R.). Hauptabteilung Sicherheit) | Unger, H.
Structural studies of the cell walls in wood of diseased conifers for estimating the wood quality
1986
Fengel, D. (Muenchen Univ. (Germany, F.R.). Inst. fuer Holzforschung)
Responses of a Norway spruce wood anatomy to elevated CO2 concentration
1999
Janous, D. | Pokorny, R. (Akademie Ved, Brno (Czech Republic). Ustav Ekologie Krajiny)