植物生态学报 ›› 2006, Vol. 30 ›› Issue (1): 47-56.DOI: 10.17521/cjpe.2006.0007
所属专题: 稳定同位素生态学
收稿日期:
2004-12-23
接受日期:
2005-08-17
出版日期:
2006-12-23
发布日期:
2006-01-30
通讯作者:
张守仁
作者简介:
*E-mail:zsr@ibcas.ac.cn基金资助:
CHEN Lan1,2, ZHANG Shou-Ren1,*()
Received:
2004-12-23
Accepted:
2005-08-17
Online:
2006-12-23
Published:
2006-01-30
Contact:
ZHANG Shou-Ren
摘要:
在北京东灵山暖温带森林生态系统中,选择常见灌丛土庄绣线菊(Spiraea pubescens),建立UV-B控制实验。连续3个生长季每天增补9.4 kJ·m-2的辐射剂量,模拟臭氧衰减17%时近地表面UV-B辐射的增强。该实验的目的是在野外环境下观测,长时间人工增强UV-B辐射对土庄绣线菊叶片的气孔导度、碳同位素比率(δ13C)、叶含水量、叶面积、特别是水分利用效率(WUE)和叶片全氮含量等指标的影响。实验结果表明,增强UV-B辐射显著减少了土庄绣线菊的叶面积(50.1%),提高了叶片全氮含量(102%)。同时,UV-B辐射还在一定程度上(尽管统计显示不显著)降低了气孔导度(16.1%)、胞间CO2浓度与大气CO2浓度之比(Ci/Ca) (4.0%)、提高了碳同位素比率(δ13C)(20.5‰)、叶含水量(3.1%)及比叶重(SLW)(5.2%),从而导致WUE的增加(4.1%)和植物的抗旱能力增强。值得注意的是,深层土壤(30~40 cm)含水量变化会影响气孔导度、δ13C和WUE对紫外辐射的响应程度:在土壤干旱的季节(6月和9月),气孔导度、δ13C、WUE这些指标处理和对照的差异很小,但是当土壤水分充足时(7月和8月),处理和对照的差异就较为显著。另外,随着实验处理时间的延长,UV-B的效应变得不显著。相关分析表明,UV-B辐射降低了土壤含水量(30~40 cm)与土庄绣线菊叶含水量、δ13C、Ci/Ca和气孔导度的相关系数,增强了WUE与土壤含水量的相关性,这也许是由于UV-B辐射增强了WUE对土壤水分变化的敏感性。该研究的结果表明UV-B辐射对土庄绣线菊的形态和生长有显著的影响,但对主要水分生理指标影响不显著。
陈兰, 张守仁. 增强UV-B辐射对暖温带落叶阔叶林土庄绣线菊水分利用效率、气孔导度、叶氮素含量及形态特性的影响. 植物生态学报, 2006, 30(1): 47-56. DOI: 10.17521/cjpe.2006.0007
CHEN Lan, ZHANG Shou-Ren. EFFECTS OF ENHANCED UV-B RADIATION ON WATER USE EFFICIENCY, STOMATAL CONDUCTANCE, LEAF NITROGEN CONTENT AND MORPHOLOGICAL CHARACTERISTICS OF SPIRAEA PUBESCENS IN A WARM-TEMPERATE DECIDUOUS BROAD-LEAF FOREST. Chinese Journal of Plant Ecology, 2006, 30(1): 47-56. DOI: 10.17521/cjpe.2006.0007
时间 Time | 2002 | 2003 | 2004 | ||||||||||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
6月 Jun. | 7月 Jul. | 8月 Aug. | 9月 Sept. | 6月 Jun. | 7月 Jul. | 8月 Aug. | 9月 Sept. | 6月 Jun. | 7月 Jul. | 8月 Aug. | 9月 Sept. | ||||||||||||||
月降雨量 Monthly precipitation (MP) (mm) | 118.1 | 125.0 | 60.4 | 90.5 | 78.6 | 87.2 | 61.3 | 82.7 | 78.1 | 227.2 | 95.8 | 57.4 | |||||||||||||
大气相对湿度 Relative humidity (RH) (%) | 79 | 84 | 89 | 85 | 78 | 86 | 86 | 86 | 77 | 87 | 90 | 82 | |||||||||||||
月平均温度 Monthly mean temperature (MT) (℃) | 16.1 | 19.0 | 17.6 | 11.8 | 15.5 | 17.6 | 16.5 | 13.0 | 16.4 | 17.6 | 15.9 | 12.1 | |||||||||||||
叶片空气水气压亏缺 Leaf-to-air | UV-B | - | - | - | - | - | - | - | - | 8.65 | 7.24 | 6.06 | 6.06 | ||||||||||||
vapour pressure deficit (VPD) (hPa) | 对照 Control | - | - | - | - | - | - | - | - | 8.67 | 7.12 | 6.07 | 6.26 | ||||||||||||
空气CO2浓度 Air CO2 concentration (Ca) (μmol·mol-1) | - | - | 370.4 | ||||||||||||||||||||||
空气CO2的碳同位素比率 Carbon isotope ratio (δ13C ) (‰) | - | - | -10.34 |
表1 试验样地近3年来的主要环境因子
Table 1 Environmental factors of the experimental site in recent three years
时间 Time | 2002 | 2003 | 2004 | ||||||||||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
6月 Jun. | 7月 Jul. | 8月 Aug. | 9月 Sept. | 6月 Jun. | 7月 Jul. | 8月 Aug. | 9月 Sept. | 6月 Jun. | 7月 Jul. | 8月 Aug. | 9月 Sept. | ||||||||||||||
月降雨量 Monthly precipitation (MP) (mm) | 118.1 | 125.0 | 60.4 | 90.5 | 78.6 | 87.2 | 61.3 | 82.7 | 78.1 | 227.2 | 95.8 | 57.4 | |||||||||||||
大气相对湿度 Relative humidity (RH) (%) | 79 | 84 | 89 | 85 | 78 | 86 | 86 | 86 | 77 | 87 | 90 | 82 | |||||||||||||
月平均温度 Monthly mean temperature (MT) (℃) | 16.1 | 19.0 | 17.6 | 11.8 | 15.5 | 17.6 | 16.5 | 13.0 | 16.4 | 17.6 | 15.9 | 12.1 | |||||||||||||
叶片空气水气压亏缺 Leaf-to-air | UV-B | - | - | - | - | - | - | - | - | 8.65 | 7.24 | 6.06 | 6.06 | ||||||||||||
vapour pressure deficit (VPD) (hPa) | 对照 Control | - | - | - | - | - | - | - | - | 8.67 | 7.12 | 6.07 | 6.26 | ||||||||||||
空气CO2浓度 Air CO2 concentration (Ca) (μmol·mol-1) | - | - | 370.4 | ||||||||||||||||||||||
空气CO2的碳同位素比率 Carbon isotope ratio (δ13C ) (‰) | - | - | -10.34 |
变异来源 Variation | df | 气孔导度 Stomatal conductance | δ13C值 Carbon isotope ratio | 水分利用 效率 WUE | 叶含水量 Leaf water content | 胞间CO2浓 度与大气CO2 浓度之比 Ci/Ca | 叶面积 Leaf area | 比叶重 SLW | 全氮含量 Total N content | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
F | p | F | p | F | p | F | p | F | p | F | p | F | p | F | p | |||||
主效应 Main effects | ||||||||||||||||||||
UV-B | 1 | 2.105 | ns | 0.699 | ns | 1.165 | ns | 4.034 | ns | 0.936 | ns | 23.601 | *** | 3.283 | ns | 15.766 | ** | |||
时间 Time | 3 | 5.81 | * | 4.073 | * | 24.457 | *** | 3.58 | * | 4.014 | * | 0.291 | ns | 2.726 | ns | 1.257 | ns | |||
二元交互 Two-factor interaction effects | ||||||||||||||||||||
UV-B×时间 UV-B×Time | 3 | 0.658 | ns | 1.179 | ns | 1.164 | ns | 0.228 | ns | 0.927 | ns | 0.096 | ns | 0.296 | ns | 1.764 | ns |
表2 UV-B辐射和时间两因素对气孔导度、δ13C值、叶含水量、WUE、叶面积、叶比重和全氮含量的影响
Table 2 Effects of UV-B, time and their interactions on stomatal conductance, δ13C, leaf water content, water use efficiency (WUE), intercellular CO2 concentration/air CO2 concentration/air CO2 concentration (Ci/Ca), leaf area, specific leaf weight (SLW) and total N content
变异来源 Variation | df | 气孔导度 Stomatal conductance | δ13C值 Carbon isotope ratio | 水分利用 效率 WUE | 叶含水量 Leaf water content | 胞间CO2浓 度与大气CO2 浓度之比 Ci/Ca | 叶面积 Leaf area | 比叶重 SLW | 全氮含量 Total N content | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
F | p | F | p | F | p | F | p | F | p | F | p | F | p | F | p | |||||
主效应 Main effects | ||||||||||||||||||||
UV-B | 1 | 2.105 | ns | 0.699 | ns | 1.165 | ns | 4.034 | ns | 0.936 | ns | 23.601 | *** | 3.283 | ns | 15.766 | ** | |||
时间 Time | 3 | 5.81 | * | 4.073 | * | 24.457 | *** | 3.58 | * | 4.014 | * | 0.291 | ns | 2.726 | ns | 1.257 | ns | |||
二元交互 Two-factor interaction effects | ||||||||||||||||||||
UV-B×时间 UV-B×Time | 3 | 0.658 | ns | 1.179 | ns | 1.164 | ns | 0.228 | ns | 0.927 | ns | 0.096 | ns | 0.296 | ns | 1.764 | ns |
水分利用效率 WUE | 叶含水量 Leaf water content | δ13C值 Carbon isotope ratio | 胞间CO2浓度与 大气CO2浓度 之比Ci/Ca | 气孔导度 Stomatal conductance | ||
---|---|---|---|---|---|---|
UV-B | Pearson correlation | 0.623* | -0.467 | -0.078 | 0.073 | 0.275 |
Sig. (2-tailed) | 0.03 | 0.126 | 0.81 | 0.822 | 0.475 | |
n | 12 | 12 | 12 | 12 | 9 | |
对照 | Pearson correlation | 0.604 | -0.731* | -0.608 | 0.540 | 0.711 |
Control | Sig. (2-tailed) | 0.113 | 0.04 | 0.11 | 0.168 | 0.114 |
n | 8 | 8 | 8 | 8 | 6 |
表3 土壤含水量和水分利用效率、叶含水量、δ13C、胞间CO2浓度与大气CO2浓度之比、气孔导度的相关系数
Table 3 Correlation coefficients between soil water content and water use efficiency (WUE), leaf water content, δ13C, intercellular CO2 concentration/air CO2 concentration (Ci/Ca), stomatal conductance
水分利用效率 WUE | 叶含水量 Leaf water content | δ13C值 Carbon isotope ratio | 胞间CO2浓度与 大气CO2浓度 之比Ci/Ca | 气孔导度 Stomatal conductance | ||
---|---|---|---|---|---|---|
UV-B | Pearson correlation | 0.623* | -0.467 | -0.078 | 0.073 | 0.275 |
Sig. (2-tailed) | 0.03 | 0.126 | 0.81 | 0.822 | 0.475 | |
n | 12 | 12 | 12 | 12 | 9 | |
对照 | Pearson correlation | 0.604 | -0.731* | -0.608 | 0.540 | 0.711 |
Control | Sig. (2-tailed) | 0.113 | 0.04 | 0.11 | 0.168 | 0.114 |
n | 8 | 8 | 8 | 8 | 6 |
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