云杉树木木质部汁液中有机硫和无机硫的运输以及硫收支情况

Organic and inorganic sulfur transport in the xylem sap and the sulfur budget of Picea abies trees.

作者信息

Köstner Barbara, Schupp Robert, Schulze Ernst-Detlef, Rennenberg Heinz

机构信息

Lehrstuhl Pflanzenökologie I der Universität Bayreuth, 95440 Bayreuth, Germany.

出版信息

Tree Physiol. 1998 Jan;18(1):1-9. doi: 10.1093/treephys/18.1.1.

DOI:10.1093/treephys/18.1.1

PMID:12651293

Abstract

Temporal changes in inorganic and organic sulfur compounds (sulfate, glutathione, cysteine, methionine) were analyzed in xylem sap of 40-year-old Norway spruce (Picea abies (L.) Karst.) trees growing on acidic soils at a healthy and a declining stand in the Fichtelgebirge (North Bavaria, Germany). Studies were carried out (1) to quantify glutathione (GSH) transport in the xylem of spruce, (2) to study the significance of reduced sulfur versus sulfate (SO(4) (2-)) transport in the xylem, and (3) to compare total sulfur (S) transport in the xylem with the amount of foliar uptake of SO(2) in an air-polluted environment. Glutathione was the main reduced S compound in the xylem ranging in concentration from 0.5 to 5 &mgr;mol l(-1). Concentrations of inorganic SO(4) (2-) in the xylem sap were up to 50 times higher than those of GSH ranging from 60 to 230 &mgr;mol l(-1). During the growing season, concentrations of all S compounds in the xylem were highest in May (up to 246 &mgr;mol l(-1)) and decreased during summer and fall (up to 21 &mgr;mol l(-1)). On average, SO(4) (2-) concentrations in xylem sap were 30% higher at the declining site compared with the healthy site. Diurnal changes in organic S compounds were significant for GSH and cysteine with high concentrations during the night and low concentrations during the day. Diurnal changes in inorganic concentrations were not significant. Xylem sap concentrations of SO(4) (2-) and cysteine were twice as high and GSH concentrations were tenfold higher in surface roots than in branches. At both sites, transport of organic S was low (up to 3% of total S) compared to transport of SO(4) (2-). Annual transport of total S in the xylem (SO(4) (2-) was the main component) ranged from 60 to 197 mmol tree(-1) year(-1) at the healthy site and from 123 to 239 mmol tree(-1) year(-1) at the declining site. Although gaseous uptake of SO(2) was estimated to be similar at both sites (38 mmol tree(-1) year(-1); Horn et al. 1989), the ratio between annual gaseous uptake of SO(2) and transport of S in the xylem was 1:4 and 1:5 at the healthy and declining sites, respectively.

摘要

对生长在德国北巴伐利亚菲希特尔山酸性土壤上健康和生长衰退林分中40年生欧洲云杉（Picea abies (L.) Karst.）树木木质部汁液中的无机和有机硫化合物（硫酸盐、谷胱甘肽、半胱氨酸、蛋氨酸）的时间变化进行了分析。开展的研究包括：（1）量化云杉木质部中谷胱甘肽（GSH）的运输；（2）研究木质部中还原态硫与硫酸盐（SO₄²⁻）运输的重要性；（3）在空气污染环境中，比较木质部中总硫（S）的运输与叶片对SO₂的吸收量。谷胱甘肽是木质部中主要的还原态硫化合物，浓度范围为0.5至5 μmol l⁻¹。木质部汁液中无机SO₄²⁻的浓度比谷胱甘肽高50倍，范围为60至230 μmol l⁻¹。在生长季节，木质部中所有硫化合物的浓度在5月最高（高达246 μmol l⁻¹），在夏季和秋季降低（高达21 μmol l⁻¹）。平均而言，生长衰退林分木质部汁液中SO₄²⁻的浓度比健康林分高30%。有机硫化合物的日变化对谷胱甘肽和半胱氨酸而言显著，夜间浓度高，白天浓度低。无机浓度的日变化不显著。表层根中SO₄²⁻和半胱氨酸的木质部汁液浓度是树枝中的两倍，而谷胱甘肽浓度是树枝中的十倍。在两个林分中，与SO₄²⁻的运输相比，有机硫的运输量较低（占总硫的3%）。健康林分木质部中总硫的年运输量（SO₄²⁻是主要成分）为60至197 mmol·树⁻¹·年⁻¹，生长衰退林分为123至239 mmol·树⁻¹·年⁻¹。尽管估计两个林分对SO₂的气态吸收量相似（38 mmol·树⁻¹·年⁻¹；Horn等人，1989），但在健康林分和生长衰退林分中，SO₂的年气态吸收量与木质部中硫运输量的比值分别为1:4和1:5。