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The correlation between the volatile organic compound emissions and the vegetation succession of the ecosystems in different climatic zones of China

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  • Sudden Oak Life

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Isoprene and stored volatile organic compound (VOC) emissions along the succession of ecosystem in tropical, subtropical and temperate areas were characterized using a portable hydrocarbon detector and GCMS-AED analysis. Isoprene emissions were observed to exhibit an ecological pattern whereby emissions were highest in early to middle successional (development) woodland and forest communities, and relatively low in late successional forest and peatland communities. This pattern may result from the ability of isoprene to enhance the availability of nitrogen that is deposited in the strongly nitrogen limited ecosystems. These findings from China along with the similar findings from North America, Puerto Rico, central Amazon, and central Africa point to characteristic growth from structure and VOC chemistry that ecosystems may share globally. This successional pattern would be useful in building a simple ecosystem-based, instead of painstaking species-based, model of VOC emission.
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中国不同气候带植被挥发性有机化合物通量
与生态系统演替的相关性
李庆军
1,23
 Lee F. KLINGER
2
(1. 中国科学院西双版纳热带植物园 ,云南勐腊 666303 ;
2. The National Center for Atmospheric Research, Boulder , CO80307 ,USA)
摘要 : 从群落水平和生态系统演替的角度对中国热带亚热带和温带生态系统植物挥发性有机化合物(VOC)通量
的研究表明 ,异戊二烯通量呈现出在生态系统演替的早期到中期阶段随着演替的进行而升高 ,在先锋性灌木和乔
木阶段达到高峰 ,然后又随着演替的发展而逐渐下降的演替格局 ,而其他 VOC 通量则有随着演替的进行而上升的
趋势生态系统不同演替阶段异戊二烯通量的变化可能与植物获取养分氮有关 ;根据植物 VOC释放通量的生态演
替格局 ,可以建立全球陆地生态系统的 VOC 模型 ,对大气化学过程中的 VOC时空动态进行很好的模拟
关键词 : 西双版纳 ;哀牢山;长白山 ;生态系统演替;挥发性有机化合物通量;异戊二烯
中图分类号 : Q948. 1    文献标识码 : A    文章编号 : 057727496(2001)1021065207
The Correlation Between the Volatile Organic Compound Emissions and the
Vegetation Succession of the Ecosystems in Different Climatic Zones of China
LI Qing-Jun1,23, Lee F. KLINGER2
(1. Xishuangbanna Tropical Botanical Garden, The Chinese Academy of Sciences , Mengla , Yunnan 666303 , China ;
2. The N ational Center for Atmospheric Research , Boulder , CO80307 , USA)
Abstract :  Isoprene and stored volatile organic compound (VOC)emissions along the succession of ecosystem
in tropical , subtropical and temperate areas were characterized using a portable hydrocarbon detector and GC-
MS-AED analysis. Isoprene emissions were observed to exhibit an ecological pattern whereby emissions were
highest in early to middle successional (developmental)woodland and forest communities , and relatively low in
late successional forest and peatland communities. This pattern may result from the ability of isoprene to en2
hance the availabilityof nitrogen that is deposited in the strongly nitrogen limited ecosystems. These findings
from China along with the similar findings from North America , Puerto Rico , central Amazon , and central
Africa point to characteristic growthform structure and VOC chemistry that ecosystems may share globally. This
successional pattern would be useful in building a simple ecosystem-based , instead of painstaking species-
based , model of VOC emission.
Key words :  Xishuangbanna ; Ailao mountain ; Changbai mountain ; ecosystem succession ; volatile organic
compound flux ; isoprene
  地球表面的大气层决定着地球上的候和
,对地球表面的生物和生命过程具有重大的影响;
大气中各种化学成分的组成含量及其相互转化 ,
接影响着地球表面的环境状况 ,其中 ,大气中某些化
学物质(例如酸雨臭氧)在地球表面的分布 ,对生物
圈具有直接的影响 ,在一些地区已经成为当地主要
的环境问题[1] 。非甲烷碳氢化合物(NMHC)是由地
球上的各种生物学和地学过程产生的痕量气体 ,
大气中的含量虽然很,但却对某些大气中的化学
过程具有决定性的作用NMHC 的释放量为 1 273
Tg Cyr - 1 (每年 1 273 ×1012 g C 含量),在人口稠密
的城市和工业化地区 ,人类活动释放的 NMHC 占有
不可低估的地位 ,但就全球而言 ,绝大多数的 NMHC
是从自然界中释放出来的[2] ,其中仅有很少的一部
分来自海洋 ,其余大部分来自陆地生态系统中的植
,别是木本植物,其挥发性有机化合物 (volatile
organic compounds ,VOC)的排放量占到全球 NMHC
量的 90 %以上(1 150 Tg Cyr - 1)[2 ] 植物VOC 主要
是通过植物的叶面挥发到大气中去的 ,其成分和结
构数以百计 ,但其中的两类化合物占到一半以上 ,
Ξ收稿日期: 2001202223  接受日期: 2001204223
基金项目:国家自然科学基金(3970001940075027 和国际合作项目美-022)资助 ,同时得到美国国家大气研究中心的资助 ,该中心由美国国家科
学基金会支持Supported by the National Natural Science Foundation of China (39700019 , 40075027 and US-022)and the Scholarly Studies Program of the
National Center for Atmospheric Research which is sponsored by the National Science Foundationof America.
3通讯作者Aut hor for correspondence . E- mail : < qjlixtbg @bn. yn. cninfo. net > .
植  物  学  报  2001 , 43 (10):1065 - 1071        Ξ
Acta Botanica Sinica
类是含有 5个碳原子的异戊二烯(isoprene , C5H8),
一类是含有 10 个碳原子的单萜类化合物
(monoterpenes , C10 Hx),例如α
-蒎烯 (α
-pinene),这两
类挥发性化合物从植物中释放的总量分别500
125 Tg Cyr- 1 [2 ,3 ]
许多植物在特定的自然条件下能够释放 VOC ,
这些化合物不但在生态系统的演替进程中起到关键
的作用 ,例如缓解热胁迫[4] 抵御昆虫啃食[5 ] 从空
气中摄取气态氮以满足生态系统演替早期阶段对氮
素的需求[6]。同时 ,VOC 的释放对于植被上层空
气对流层的大气化学过程具有显著的影响 ,对周围
环境产生明显的反馈VOC 具有极高的化学
活性 ,能够与大气中的 OHH2O等发生复杂的化学
反应 ,植物中 VOC 释放率及其在大气中的含量控制
着大气中的 OH 离子浓度 ,从而决定着大气中甲烷
(CH4)CO 等温室气体的浓度 ,而这些气体又影响
着大气中的辐射平衡 ,进而影响到全球热量和降水
的时空分布格局 ,对区域乃至全球环境和气候产生
强烈影[7 ,8 ] 另一方面,大量研究证[ 9 - 14 ] VOC
对于近地大气对流层中臭氧的光化学合成具有显著
的影响 ,而大气对流层中臭氧浓度的上升 ,会导致森
林衰退农作物产量下降等严重的生态后果[ 15 - 18 ] ;
大气中的 VOC 还在全球碳循环过程中扮演着重要
的角[9 ] 。因,对大气中生物挥发性化合物
(BVOC)特别是对各类生态系统中植物释放的 VOC
通量的测定对于成功实行对流层臭氧控制具有重要
的意义
不同的植物类群释放的 VOC 种类和数量不
例如异戊二烯是一种由植物释放的最丰富的 VOC ,
它的释放依赖于充足的光照和较高的温度[19] ,
主要的植物分类群中都有特定类群能够释放异戊二
,如苔藓植(特别是泥炭藓属 Sphagnum)
植物 (如满江红属 Azolla)裸子植物(
Picea)和被子植物(如壳斗科 Fagaceae)。在被子
植物中 ,栎属(Quercus)悬铃木属 (Platamus)
(Populus)(Rhamnus)(Salix)和桉属
(Eucalyptus)等是典型的异戊二烯释放者,而槭属
(Acer)柑橘属(Citrus)木兰属(Magnolia)等属主要
释放萜烯类化合物[20 ,21] 通过对植物系统进化及
其与释放 VOC 相互关系的研究 ,Guenther [3]建立
了一个全球 VOC 的释放模型 ,对温带生态系统的结
与其大气环境的相互关系做了较好的解释
,这一模型是建立在不同植物类群释放 VOC
类和能力的基础上 ,需要对大量植物种类进行野外
和实验室测试和分析 ,不仅工作量大 ,而且由于测试
条件和环境不同 ,所得到的释放量也会有较大的差
一些地区的研究表明 ,VOC 的释放与生态系统
类型具有明显的相关,与生态系统所处的环境条
件密切相[6 - 8 ,19 ,22 ] 进一步的研究还表明 ,各类
生态系统中植物 VOC 的释放具有与生态系统演替
相关的格局[8 ,22 ] ,生态系统的早期到中期演替阶段
具有较强的释放异戊二烯的能力 ,释放异戊二烯较
强的植物多是这一演替阶段的主要成分(Quer2
cusPopulusSalix Picea ),演替后期的植
类多为萜烯类化合物的释放者(PinusAbies
MagnoliaTaxodium )演替是生态系统发展的过
,其结果是群落结构和物种组成不同的植被类型
(不同演替阶段)的不断更迭在生态系统的演替过
程中 ,生产力生物量、养分循环和能量流动具有
广泛的可预测性[ 23 - 25 ] 如果 VOC 的释放与生态系
统的演替相关联 ,那么沿着生态系统的演替序列就
能找出 VOC 释放的系统性规律 ,利用这一规律建
以生态系统的演替为基础的 VOC 释放模型 ,能够
取代烦琐的以种类为基础的 VOC 释放模型
1 材料和方法
1. 1  研究地点及样地的选择
研究地点选择在云南省西双版纳自然保护区勐
补蚌;哀牢山自然保护区徐家坝和吉林省长白山
自然保护区 ,分别代表热带亚热带和温带陆地生态
系统 ,选择代表性的植物群落类型 ,沿演替方向设置
10 m 宽的样带 ,样带长度视地形及群落演替程度从
70 m 100 m 不等 ,30 条样带 ,样带的立地状况
见表 2
1. 2  样品采集和分析
野外工作于 1998 86日至 11 8日先后
在长白山西双版纳和哀牢山进行记录样带内所
有木本植物及优势草本植物 ,测定每株乔木的胸径
(DBH)高度单位叶面积干重(SLDW)群落总叶面
积指数(TLAI)及乔木层叶面积指数(TTLAI)演替状
况等群落生态学特征,同时记录海拔坡度坡向
形及土壤等环境特征 ,详细方法见文献[8 ,26]
在所有样带中 ,共记录到 443 种植物 ,大都是木
本植物 ,其中西双版纳 8条样带中共记录了 200 ;
哀牢山 9条样带中共记录了 147 ;长白山 13 条样
带中共记录到96 利用580 型手持式光电离子
探测器(photoionization detector , PID ,Thermo En2
vironmental Instruments Inc. 公司生产)测定了 208
1066  植  物  学  报   Acta Botanica Sinica 43
主要成分的 VOC 潜在通量 ,即植物在理想或近于理
想的温度和光照条件下 VOC 的释放能力PID 能够
灵敏地探测到总 VOC 排放量并通过光照和遮光的
对照探测到植物异戊二烯的排放量 ,详细方法见文
[8 ,27]
为了验证 PID 技术的精确度和可靠性 ,我们对
63 种优势植物(其中热带 28 ,亚热带 19 ,温带
16 )进行了封闭采样(enclosure sampling),将采集
到的样品带到美国国家大气研究中心(NCAR)利用
气相色谱-质谱技术 (GC-MS)和原子蒸发探测技术
(atomic emission detection , AED)分析包括异戊二烯
(isoprene)在内的 C3C15的一系列 VOC 的含量 ,
细方法见文献[8 ,28]
1. 3  VOC通量的计算
VOC 的通量表示在理想条件下某植物群落单
土地面积在单位时间内向大气中排放 VOC 的质
,它是通过先计算群落中主要木本植物的叶生物
(TBM),再根据 PID GC-MS-AED 测定的 VOC
放能力计算出每种植物的 VOC 通量 ,最后将群落
地中所有主要植物的 VOC 排放量累加并除以样地
面积由于异戊二烯是植物排放的主VOC ,
VOC 40 %60 %[1 ] ,故这里将其单独列出;
OVOC 是指植物在无损伤状态下排放的除异戊二烯
外的其他 VOC ;SVOC 是指储存于植物体内 ,只有在
植物受到损伤时才释VOC详细方法见文献
[8 ,26]
2 实验结果
2. 1  PID 探测结果与气-质连动-子挥发
测技术( GC-MS- AED)分析结果的一致性
利用 PID 在野外进行植物 VOC 释放特性的测
定具有方便快捷的优点 ,但也具有定量性较差的问
为了检验 PID 测定结果与采样后在实验室利
GC-MS-AED 分析结果一致,我们对 63 种优势
植物的野外和室内分析结果进行了比较(1),
23 种释放异戊二烯的植物中, PID 探测出 22
(96 %),18 释放萜烯类化合物的植物都被 PID
检测到(100 %);40 种非异戊二烯释放者和 37
非萜烯类化合物释放者中 ,PID 分别判断出了 37
(93 %)37 (100 %)PID 在用做野外快速
测定植物释放 VOC 释放特性上具有很好的定性能
此外 ,PID 还能对异戊二烯的释放能力作初步
的定量测定 ,如表 1所示 ,在检测出的 22 种异戊二
烯释放者中 ,PID 准确的判断出了其中 21 种的释
(H表示强释放者,分析结果为 > 10μ
g Cg- 1
h- 1 ;M 表示中度释放者 ,分析结果为 1 - 10μ
g C
g- 1h- 1 ;L 为弱释放者 ,分析结果为 < 1μ
g Cg- 1
h- 1)然而 ,PID 在判断萜烯类化合物的释放量时
误差较大 ,18 种释放者中仅定量测出 8,其余 10
种中的 9种都偏高
1 中国不同气候带生态系统不同演替阶段 63 种优势植物 PID 探测结果与 GC-MS-AED 分析结果的比较
Table 1  Comparison of PID method with GC-MS-AED method of determining isoprene and terpene emi ssion potential for 63 species of Chinese
plants
Species      Family      Growth form Emission potential
Isoprene Terpene  Measured emissions (μ
g Cg- 1h- 1)
Isoprene Terpene
Acer barbinerve Aceraceae dbt N M 0. 00 0. 26
A. mono Aceraceae dbt N M 0. 00 0. 42
Alangium kurzii Alangiaceae dbt N N 0 . 00 0. 00
Mangifera indica Anacardiaceae ebt H N 2 . 64 -
Rhus chinensis Anacardiaceae dbt L M 0 . 18 1. 56
Acanthopanax evodiaefolius Arecaceae dbt N N 0. 00 0 . 00
Cocos nucifera Arecaceae ebt H N 63. 12 -
Mahonia conferta Berberidaceae ebs M N 4. 63 0. 00
Betula dahurica Betulaceae dbt N L 0 . 00 0. 12
B. ermanii Betulaceae dbt N L 0. 00 0 . 91
B. fruticosa Betulaceae dbs N L 0. 00 1 . 40
B. platyphylla Betulaceae dbt N L 0. 00 16. 52
Dolichandrone stipulata Bignoniaceae dbt N N 0 . 00 0. 00
Cassia alata Caesalpiniaceae ebs N N 0 . 00 -
Terminalia bellirica Combretaceae dbt N N 0 . 00 0. 00
Crypteronia paniculata Crypteroniaceae ebt N N 0 . 02 0. 00
Shorea wangtanshuea Dipterocarpaceae dbt N N 0 . 00 0. 00
Ledum palustre Ericaceae ebs N H 0 . 00 31 . 46
Rhododendron irroratum Ericaceae ebt N N 0 . 00 0. 00
Vaccinium duclouxii Ericaceae ebt N N 0. 00 0 . 00
V. uliginosum Ericaceae ebs N L 0 . 00 1. 13
Flueggea virosa Eup horbiaceae ebs H N 159. 80 0. 00
10 期 李庆军等:中国不同气候带植被挥发性有机化合物通量与生态系统演替的相关性 1067 
1() Table 1 (continued)
Species      Family      Growth form Emission potential
Isoprene Terpene  Measured emissions (μ
g Cg- 1h- 1)
Isoprene Terpene
Hevea brasiliensis Eup horbiaceae dbt H N 0 . 00 0. 00
Mallotus paniculatus Euphorbiaceae dbt L M 0 . 25 0. 14
Ricinus communis Eup horbiaceae ebt N N 0 . 00 -
Maackia amurensis Fabaceae dbt H N 135. 64 0. 00
Castanopsis orthacantha Fagaceae ebt N N 0 . 00 0. 00
Lithocarpus xylocarpus Fagaceae ebt N N 0 . 00 0. 00
Quercus mongolicus Fagaceae dbt H N 347. 86 0. 00
Cratoxylon cochinchinensis Hypericaceae dbt H N 18. 41 0 . 00
Garcinia cowa Hypericaceae ebt N N 0 . 00 0. 00
G. xanthochymus Hypericaceae ebt M N 2. 96 0. 00
Illicium micranthum Illiciaceae ebt N N 0. 00 0 . 00
Melia toosenden Meliaceae dbt N N 0 . 00 0. 00
Adenanthera pavonina Mimo saceae dbt M N 5. 21 0 . 00
Albizia lucidior Mimosaceae dbt H N 26. 78 0. 00
Broussonetia papyrifera Moraceae ebt M N 6. 16 0 . 00
Ficus fistulosa Moraceae ebt H M 207. 00 0 . 72
F. hispida Moraceae ebt H N 0 . 00 0. 00
F. langkokensis Moraceae ebt H N 29. 66 0 . 00
Myristica yunnanensis Myristicaceae ebt H N 37. 77 0 . 00
Millettia leptobotrya Papilionaceae ebt N N 0 . 00 0. 00
M. pulchra Papilionaceae dbt H N 20. 80 0. 00
Larix olgensis Pinaceae dnt N M 0 . 00 3. 80
Picea jezoensis Pinaceae ent M H 7 . 24 5. 17
P. koreana Pinaceae ent M H 0 . 00 0. 30
Pinus armandi Pinaceae ent N H 0 . 00 0. 39
P. koraiensis Pinaceae ent N H 0. 00 0 . 26
P. yunnanensis Pinaceae ent N H 0 . 00 0 . 17
Podocarpus imbricatus Podocarpaceae ent N N 0 . 00 0. 00
P. macrophylla Podocarpaceae ent N N 0 . 00 0. 00
Dichotomanthus tristaniaecarpoa Rosaceae ebs N N 0. 00 0 . 00
Spiraea japonica Rosaceae dbs N H 0. 00 5 . 28
Populus koreana Salicaceae dbt H L 63. 12 -
Salix matsudana Salicaceae dbt H L 63 . 12 -
S. viminalis Salicaceae dbs H N 136. 50 0 . 00
Theobroma cacao Sterc uliaceae ebt N N 0 . 00 -
Symplocos dryophila Symplocaceae ebt N N 0 . 00 0. 00
Anneslea fragrans Theaceae ebt N N 0. 00 0 . 00
Schima wallichii Theaceae e bt N N 0 . 00 0. 00
Microcos nervosa Tiliaceae ebt H N 32. 61 0 . 00
Celtis tetrandra Ulmaceae ebt N N 0 . 00 0. 00
Trema orientalis Ulmaceae ebt N N 0. 00 0 . 00
ebt , evergreen broadleaf tree ; ebs , evergreen broadleaf shrub; ent , evergreen needle leaf tree ; dbt , deciduous broadleaf tree ; dbs , deciduous broadleaf shrub ;
dnt , deciduous needle leaf tree ; H , high emission potential ; M , middle emission potential ; L , low emission potential ; N , no emission detected.
2. 2  不同植物类群释放 VOC的种类及释放量
从表 1的结果可以看出 ,虽然不同地区不同的
植物种类释VOC 的种类及数量不同,VOC
释放特性与植物所属的类群有很密切的相关性
属的水平上看 ,马鞍树属(Maackia)栎属蹄甲属
(Bauhinia)榕属(Ficus)Populus Salix 等属中的
大部分种类具有释放异戊二烯的能力 ,而且大多数
种类都是强释放者(释放通量 > 10μ
g Cg- 1h- 1);
而槭属(Acer)桦属(Betula)落叶松(Larix)云杉
(Picea)和松属(Pinus)等属多为萜烯类化合物释
放者从科的水上看 ,漆树科(Anacardiaceae)3/ 5
(释放种数/定种,下同)榈科 (Arecaceae)2/
2禾本科 (Gramineae)5/ 5含羞草科(Mimosaceae)4/
6桑科(Moraceae)7/ 11 和杨柳科 (Salicaceae)5/ 5
中多数种属为异戊二烯释放者,桦木科(Betu2
laceae)3/ 3 和松科(Pinaceae)5/ 8 中的种类多释放其
他萜烯类化合物。从以上分析可以看出 ,释放异戊
二烯的类群多为在生态系统演替早期占势的
,演替后期的优势植物类群多为萜烯类化合物的
放者。植物除了释放异戊二烯和萜烯类化合物
,在组织和器官受到物理损伤后 ,多数植物能够释
放出一些储藏性 VOC(SVOC),在所测定的 255 种植
物中 ,210 种具有这类储藏性 VOC ,其中 1/ 3 具有
很高的释放量
2. 3  不同植被类型的 VOC通量
2给出了热带亚热带和温带生态系统中不
1068  植  物  学  报   Acta Botanica Sinica 43
2 中国不同气候带植物群落的 VOC 通量
Table 2  Site mean of potential VOCfluxesof plant communities in different climate zone of China
Site   Plant community Successional
stage1)Latitude Longitude Altitude
(m)TTLBM2)
(gm- 2)Isoprene
(mgm- 2h- 1)OVOC3)
(mgm- 2h- 1)
Xishuang-
banna
(Tropic)
Early primary forest 21°507N 101°623E 565 427. 20 0. 112 3 0. 009 6
Moss forest 21°743N 101°214E 845 377. 52 0. 134 3 0. 046 5
Depterocaupus forest 21°511N 101°608E 820 359. 40 0. 141 6 0. 011 5
Pometia forest 21°740N 101°201E 805 336. 73 0. 158 0 0. 009 4
Riverside forest 21°555N 101°517E 575 180. 85 0. 163 9 0. 007 6
Secondary Trema forest 21°757N 101°617E 915 199. 61 0 . 312 4 0 . 008 0
Mid-secondary forest 21°511N 101°608E 590 350. 43 0 . 455 1 0 . 032 0
Early-secondary forest 21°521N 101°614E 570 340. 18 0. 584 3 0. 006 9
Ailao Mt.
(Subt . )
Sphagnum bog 24°249N 101°132E 2460 423. 63 0. 061 5 0. 000 3
Mature Lithocarpus forest 24°141N 101°150E 2528 514 . 62 0. 089 2 0. 020 3
Heath forest 24°141N 101°150E 2640 940. 59 0 . 141 0 0 . 006 1
Old Lithocarpus forest 24°214N 101°037E 2408 444. 82 0. 145 0 0. 003 1
Moss- Camellia forest 24°141N 101°150E 2490 404. 34 0 . 158 9 0 . 004 1
Castanopsis forest 24°253N 101°227E 2515 658. 01 0 . 175 0 0. 010 0
Young Lithocarpus forest 24°234N 101°139E 2442 348. 57 0 . 208 6 0 . 017 8
Young Populus forest 24°243N 101°131E 2395 404. 93 0 . 308 3 0. 006 0
Old Populus forest 24°232N 101°138E 2415 430. 18 1 . 126 5 0 . 002 6
Changbai
Mt.
(Tem. )
Birch-larch forest 42°337N 128°352E 1863 593. 50 0 . 039 7 0. 071 7
Birch forest 42°316N 128°353E 1980 306. 28 0 . 078 1 0. 019 0
Larch bog forest 42°824N 128°628E 1200 476. 76 0 . 089 6 0 . 032 3
Grassland 42°412N 128°621E 705 127. 15 0 . 172 0 0 . 028 8
Sphagnum bog 42°150N 128°544E 1640 643. 71 0. 262 2 0. 025 9
Birch-spruce forest 42°359N 128°354E 1700 937. 55 0. 361 1 0. 235 5
Pine-spruce forest 43°834N 128°755E 745 2044. 92 0. 566 8 0 . 389 6
Larch-pine forest 42°116N 128°316E 1000 1319. 64 0. 611 4 0. 146 4
Spruce-larch forest 42°422N 128°343E 1620 1556 . 48 0. 612 4 0. 464 0
Pine-fir forest 42°332N 128°039E 1190 709. 49 0. 616 1 0. 054 5
Birch-poplar forest 42°416N 128°558E 700 362. 50 0. 795 2 0. 210 7
Spruce-fir forest 42°137N 128°351E 900 1624. 83 0. 845 5 0. 568 9
Oak-pine forest 42°416N 128°558E 705 992. 94 2. 741 2 0. 028 0
1)the successional stages are same was the Figs. 1 - 3; 2)site mean of total leaf biomass; 3)other.
同植物群落的异戊二烯和其它 VOC(OVOC)的通量 ,
以及储藏性 VOC(SVOC)的含量替序列 1 - 8
别代表生态系统演替由初期到末期的不同阶段
果表明 ,尽管不同气候带由于植物种类和环境条件
的不同 ,同一演替序列的不同群落类型的 VOC
在绝对数值上差别较,但在同一气候带内处于演
替序列初期(,
)和后期(,,
)末期(
)
植物群落 ,其异戊二烯的通量较低 ,而处于演替早期
(
)和中期(
)先锋林和次生林阶段的群落 ,其异
戊二烯通量明显较高VOC 通量最高的植物群落
在西双版纳热带生态系统为以先锋树种窄序崖豆藤
(Milletia leptobtrya)为优势的热带次生林早期,在哀
牢山亚热带生态系统中为次生小叶杨 (Populus bon2
atii)成熟林 ,在长白山温带生态系统中为次生性的
古栎-阔叶红松(Quercus mongolicus- Pinus koraien2
sis),分别为 (0. 584 3 ±0. 256 2),(1. 126 9 ±
0. 463 2)(2. 741 2 ±0. 823 1)mgm- 2h- 1 ;OVOC
的通量在数值上很低 ,但在演替后期的植物群落中
相对较高;SVOC 的含量则没有显著的规律
2. 4  植物群落 VOC通量的生态系统演替格局
演替是生态系统的重要特征之一 ,是生态系统
的结构和功能随着时间的改变而发生的改变生态
系统的演替是序的 ,是一个生态系统类型
(或阶段)代替另一个生态系统类型(或阶段)的过
,在陆地生态系统中表现为一种植物群落取代另
一种植物群落的过程 ,最终建立一种稳定的顶极状
[24 ] 如果在足够长的演替时间内没有任何干扰 ,
陆地生态系统的演替将始于种类和结构较简单的草
地阶段 ,最后归结于种类和结构较为简单的泥炭沼
[29 ] 将表 2中同一气候带的不同植物群落按照
生态系统演替序列进行综合排列后得到图 13
VOC 量变化趋势图,结果显示不论是在热带
热带还是在温带陆地生态系统中 ,植物群落的异戊
二烯通量在生态系统演替早期随着演替的发展而升
10 期 李庆军等:中国不同气候带植被挥发性有机化合物通量与生态系统演替的相关性 1069 
,在先锋木本植物群落阶段达到最高 ,然后又随着
演替的深入而下降 ,在热带生态系统中 ,最高值出现
在先锋林阶段 ,次生林也保持着较高的异戊二烯通
;在亚热带生态系统中则是次生林最高 ,先锋林次
;而在温带生态系统中 ,次生林阶段的异戊二烯通
量则远远高于其他各个阶段OVOC 则随着演替的
展而具有上升的趋势。这一 VOC 的释放格局
Klinger [8]在非洲以及 Martin Guenther[7]在北美
对不同生态系统的不同演替阶段植物 VOC 通量
变化的研究结果相一致
1. 西双版纳热带生态系统不同演替阶段挥发性有机化
合物(VOC)通量的变化
Fig.1.  The volatile organic compound (VOC)flux of different
successional stages in Xishuangbanna tropical ecosystem.
OVOC , other VOC.
2. 哀牢山亚热带生态系统不同演替阶段挥发性有机化
合物(VOC)通量的变化
Fig.2.  The volatile organic compound (VOC)flux of different
successional stages in Ailao Mt. subtropical ecosystems.
OVOC , other VOC.
3. 长白山温带生态系统不同演替阶段挥发性有机化合
(VOC)通量的变化
Fig.3.  The volatile organic compound (VOC)flux of different
successional stages in Changbai Mt. temperate ecosystems.
OVOC , other VOC.
3 讨论
植物释放 VOC 的种类和数量与植物的分类系
统有一定的相关性[21] ,根据这一相关性, Guenther
[3]建立了一个全球 VOC 的释放模型 ,对全球尺
上的 VOC 通量作了估算,这一模型是建立在
对温带植物为主进行的物种水平上 VOC 通量的
测定基础上的 ,对于种类组成较温带丰富得多的热
带和亚热带地区 ,已测定过 VOC 通量的植物种类仅
占所有种类中的很小一部分 ,运用这一模型需要进
大量的物种水平上的通量测定。如果 VOC 的释
放与生态系统的演替相关联 ,那么沿着生态系统的
演替序列就能找出 VOC 释放的系统性规律 ,利用
规律建立以生态系统的演替为基础的 VOC 释放
模型 ,就能够取代烦琐的以种类测定为基础的 VOC
释放模型[8]
对于植物释放 VOC 的生物学和生态学机制目
前还不完全清楚 ,有的认为植物释放异戊二烯是为
了缓解热胁迫[4] ,也有的认为是为了植物 VOC 能抵
昆虫对植物的啃食[5 ] Langenheim[6] 研究认为植
物排放的异戊二烯对于植物本身的反馈作用在于在
大气化学过程中与土壤硝化作用中释放的一氧化氮
(NO)反应 ,产生植物能够吸收利用的 NO2等氮化合
根据本研究及其他在生态系统尺度上的研究显
示的 VOC 释放格局 ,可以假定生态系统演替早期和
期的先锋群落和次生群落阶段 VOC 通量的加大
是为了从空气中摄取气态氮以满足生态系统演替早
期阶段对氮素的需求 ,因为不论在热带 、亚热带 ,
是在温带 ,生态系统演替的早期和中期 ,由于先锋和
次生成分生长迅速 ,氮都是植物群落发展的限制因
;而在演替后期和末期 ,由于土壤和生物体内累积
了大量的有机质 ,营养元素的循环利用降低了限制
因子的作用[ 30 ,31 ] 这一假设还需要在更广泛的地
区和生态系统中VOC 释放机制和通量进行研究
来加以证实
致谢: 感谢长白山森林生态站代力民研究员邹春
王晓春杨丽韫许浩和刘庆伟等同志;西双版纳
植物园王洪高级工程师夏永梅副研究员唐建维副
研究张光明和哀牢山生态站杨国平在野外工作
和物种鉴定方面给予的大力帮助 ,王永峰硕士生帮
助查对植物名称;感谢NCAR James Greenberg 博士协
助分析气体样品
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(责任编辑:崔金钟)
10 期 李庆军等:中国不同气候带植被挥发性有机化合物通量与生态系统演替的相关性 1071 
... The PFG concept, which groups together plants with similar ecological properties rather than plants that look similar or have similar evolutionary origins (Gitay and Noble 1997; Scholes et al. 1997; Bai et al. 2001 Bai et al. , 2004 Chen et al. 2003), differs from the traditional methods of plant classification. We used two types of PFG based on responses to a change or disturbance in a specific environmental factor, namely plant life form function groups (PLFG) and water ecological groups (WEG;Table 1Guenther et al. 1996; Klinger et al. 1998; Li and Klinger 2001; Karlik et al. 2002). In the experiments, a hand-held factory calibrated PID (ppb RAE Systems Inc. ...
... Guenther et al. (1993) have established a classic algorithm to estimate the base emission of VOC at a standard temperature (30 °C) and PAR flux (1 000 µmol · m −2 · s −1 ). The algorithm has already been supported and used successfully by some researchers (Klinger et al. 1998Klinger et al. , 2002 Li and Klinger 2001; Wang et al. 2003). The model is described briefly as follows: ...
... Therefore, grazing, especially overgrazing, will probably increase VOC emission from the temperate grassland vegetation of Inner Mongolia. Similarly, Klinger et al. (1998), Guenther et al. (1999, and Li and Klinger (2001) have also shown that isoprene and monoterpene emissions varied systematically along gradients of ecosystem development (or succession) in forest or savanna ecosystems. ...
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The biogenic volatile organic compounds (VOC) emitted by the vegetation of a terrestrial ecosystem play a key role in both regional air quality and tropospheric chemistry. To describe the general emission properties of VOC of different plant functional groups (PFG) in a typical temperate grassland in Inner Mongolia, China, we randomly selected 175 plant species and measured the quantities of isoprene and monoterpene in situ. Results showed that most plants had low VOC emission potential at the species level, especially for some dominant plants, such as Leymus chinensis Tzvel., Stipa grandis Smirn., and Agropyron cristatum Gaertn. At the PFG level, the lowest VOC emission potential was found for perennial rhizome grasses, a major PFG in a typical temperate grassland ecosystem. The effects of overgrazing and subsequent vegetation succession on the emission of VOC by different plant life form functional groups (PLFG) were also discussed. ( Managing editor: Ya-Qin HAN)
... [25] The above results extend to China the occurrence of a successional pattern in VOC emissions where the highest isoprene emissions occur in pioneer and early secondary forests, and the highest monoterpene emissions occur in late secondary and primary forests [cf. Li and Klinger, 2001]. Lower isoprene and monoterpene emissions are found in early successional grasslands and late successional peatlands. ...
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