ISWC OpenIR  > 水保所知识产出(1956---)
黄土丘陵区植被恢复过程中土壤有机碳 官能团变化的研究
李 婷
Subtype硕士
Thesis Advisor赵世 伟
2012-05
Degree Grantor中国科学院研究生院
Place of Conferral北京
Keyword植被恢复 土壤有机碳官能团 团聚体 Xanes Sr-ft
Abstract

植被恢复是黄土高原地区提高土壤有机碳(soil organic carbon,SOC)、改善土壤
结构最有效的措施之一,而了解植被恢复过程中土壤有机碳官能团的组成和含量,对加
深理解土壤有机碳化学稳定机制有积极意义。本研究应用同步辐射软X 射线(X-ray
Absorption Near Edge Structure ,XANES)及红外光谱(Synchrotron Radiation-Fourier
Transform Infrared ,SR-FTIR)方法,测定黄土高原不同类型区植被条件下土壤有机碳
官能团组成,并进行其含量的半定量分析,探讨黄土高原植被恢复过程中土壤、团聚体
中有机碳官能团组成及含量变化规律,明确植被恢复对土壤有机碳化学稳定性影响。主
要研究结果如下:
1、半干旱区天然草地恢复影响土壤有机碳官能团的含量和分布,提高土壤有机碳化
学稳定性增强。具体表现为随退耕年限增加,SOC 脂肪-C 特征峰吸收增强,土壤有机
碳各官能团相对含量都有所增加;0-5cm、10-20cm 土层土壤脂肪-C、醇-C 相对百分含
量明显增加,同时芳香-C 相对含量有增加趋势。XANES 测定结果与SR-FTIR 测定结果
基本一致,经T 检验,两种方法测定结果差异不显著(P>0.05),表明采用XANES 测
定退耕草地土壤有机碳结构变化是可行的。
2、人工苜蓿种植促进了SOC 积累,改善土壤团聚体稳定性,改变了SOC 各官能团
在各粒级团聚体中分布及含量。当生长达8 年时,效果最好;主要表现为随着种植年限
增加,>0.25mm团聚体百分比增加;饱和烷烃相对百分含量增加,且主要分布在0.25-1mm
团聚体中;脂肪-C、醇-C 相对百分含量随着粒径增大而减少,增加的脂肪-C、醇-C 主
要分布在大团聚体中,芳香-C 主要分布于<0.25mm 团聚体中,表明小团聚体中有机碳
稳定性高于大团聚体。连续种植苜蓿,其SOC 中易氧化官能团(脂肪-C,醇-C)增加
快于芳香-C,表明其对土壤有机碳增加的贡献最大。
3、次生植被演替提高了土壤、团聚体官能团含量和SOC 化学稳定性。植被恢复在
促进了SOC 中易氧化(醇-C、多糖-C、伸缩振动脂肪-C)官能团显著增加,稳定性较
强的变形振动脂肪-C、芳香-C 也增加,特别在恢复至狼牙刺至辽东栎阶段增加明显。植
被演替对0-5cm 土层SOC 官能团变化的作用明显大于20-40cm 土层。4、 演替过程中团聚体SOC 脂肪-C、醇-C、多糖-C、芳香-C 含量增加;SOC 多糖-C
主要体现在<0.25mm 团聚体中,脂肪-C、羧基-C、醇-C 分别主要体现于2-5 mm、0.5-0.25
mm 和 <0.25 mm 团聚体中。演替至顶级群落时,芳香-C 在各粒径团聚体中绝对含量明
显增加,其主要分布于<0.5mm 团聚体中。
5、半干旱区与半湿润区天然草地SOC 各官能团种类组成基本一致,而人工苜蓿草
地SOC 吸收图谱中还出现较为明显的饱和烷烃C-H 面内弯曲振动、羧基O-H 面外弯曲
振动吸收峰。上述三类草地SOC 官能团变化均表现为脂肪-C、醇-C、多糖-C 随着草地
年限增加和群落演替而逐渐增加,芳香-C 也呈现增加趋势。土壤有机碳芳香-C 增加幅
度表现为半干旱区天然草地>半湿润区草地>半干旱区人工苜蓿草地。说明在各区恢复草
地提高土壤有机碳化学稳定性的作用中,半干旱区封育草地强于半湿润区天然草地及半
干旱区人工苜蓿地。
关键词: 植被恢复,土壤有机碳官能团,团聚体, XANES, SR-FT

Other Abstract

Revegetation is one of the most effective methods for increasing soil organic carbon
(SOC), improving the stability of soil aggregates, and changing the composition of organic
carbon on the Loess plateau in China. During the process of vegetation restoration,
understanding the composition of the SOC functional groups, which is important to deepen
our understanding of SOC learning stability mechanism. This study directly measured the
distributions and composition of SOC functional groups from different revegetation ways
using XANES and SR-FTIR Spectroscopy. This study provides the first detailed investigation
of changes in SOC functional groups composition in different size aggregates during
vegetation restoration process on the Loess Plateau. This may provide fresh insights into the
effects of natural vegetation restoration on the chemical stability of SOC. The main results
and conclusions were presented as follows:
1. Vegetation restoration in semi-arid nature grassland changed the content of functional
group and distribution of SOC in different soil layers, and prompted structural stability of
SOC in the process of the grassland recovery. Peak intensity of aliphatic-C from fallowing
grasslands significantly increased with increasing years of fallowing. Results obtained by
SR-FTIR technique were analyzed which showed that compared with slop farmland, relative
content of functional groups from fallowing grasslands SOC were increased, the growing rate
of aliphatic-C , alcohols-C in 0-5cm , 10-20cm soil horizon was greater than growing rate
aromatic-C. Results obtained by soft X-ray technique are consistent with SR-FTIR, and
relative content of the same functional groups(aliphatic-C, aromatic-C) gained by two
determination methods were T-test, which was not significant (P > 0.05), indicated that using
Synchrotron radiation soft X-ray for the determination of SOC structural change of fallowing
grasslands is feasible.
2. Planting alfalfa for long time increased SOC, improved stability of aggregates, changed  the distribution and content of SOC functional groups in soil and different size aggregates.
The improvement effect was in 8 years. Percentage of > 0.25 mm aggregates increased with
the increasing of planting years. Relative content of saturated alkyl increased, and which were
fixed mainly in 0.25-1 mm aggregates. Relative content of aliphatic-C and alcohol-C
decreased with increasing of aggregate sizes. The increasing of the aliphatic-C and alcohol-C
existed major in macro-aggregates, while, aromatic-C distributed in < 0.25 mm aggregates.
The change content of functional groups in macro-aggregates were more clear than <0.25mm
aggregates, which showed that organic carbon stability of micro-aggregates was higher than
macro-aggregates, increasing of labile functional groups (aliphatic -C, alcohol-C) of SOC
were easier than aromatic-C in the process of plating. Percentage ratio of aliphatic -C,
alcohol-C, and saturated alkyl of SOC are main, and the change of those are most active, so
that increasing of aliphatic -C, alcohol-C and saturated alkyl contributed immense to the
increasing of SOC.
3. Plant succession improved chemical stability of SOC, which indicated that revegetation
can promote increases in aliphatic-C and ketone-C contents in both the 0-5 cm and 20-40 cm
soil layers, and this effect gradually increased with plant succession. Labile oxidation
functional groups of SOC (alcohol-C, polysaccharide-C, telescopic vibration aliphatic-C)
increased significantly, recalcitrant ones (deformation vibration aliphatic-C, and aromatic-C)
also increased during plant succession promoting SOC increase process. Especially,
functional groups of SOC increased obviously in Sophora viciifolia, Quercus liaotungensis
stages, the vegetation restoration improve the chemical stability of SOC. Plant succession
effected more the change of SOC from 0-5 cm soil layer than 20-40cm layer.
4. The result showed that polysaccharide-C was the most abundant in the 0.5-0.25 mm
aggregate, while carbonyl-C was found mainly in the <0.25 mm aggregate. High levels of
aliphatic-C, carboxylic-C and alcohol-C were found mainly in the 5-2 mm, 0.5-0.25 mm, and
<0.25 mm aggregations, respectively. In forest aromatic-C was mainly in <0.5mm aggregate,
and absolute content of aromatic-C from forest increased obviously in different aggregates.
5. The type of functional groups of SOC(polysaccharide-C, aliphatic-C, aromatic-C,
alcohol-C) from semi-arid nature grassland and semi-humid grassland grassland was the same,
moreover, which from planting alfalfa land included -COOH, alkane .In three grassland, the
result showed that aliphatic-C , alcohols-C, polysaccharide-C increased significantly during
the vegetation restoration process,aromatic-C perform the trend of increasing. Results
obtained by SR-FTIR technique were semiquantitative analyzed which showed that the rate
increasing of aromatic-C from the yunwu mountains grassland>Ziwuling grassland > alfalfa
land. It illustrated that structural stability of SOC enhance more in yunwu mountains
grassland than Ziwuling grassland and alfalfa land.
Key Words: the vegetation restoration process,aromatic-C perform the trend of increasing. Results
obtained by SR-FTIR technique were semiquantitative analyzed which showed that the rate
increasing of aromatic-C from the yunwu mountains grassland>Ziwuling grassland > alfalfa
land. It illustrated that structural stability of SOC enhance more in yunwu mountains
grassland than Ziwuling grassland and alfalfa land.
Key Words:Revegetation, Soil organic carbon functional groups, Aggregates, XANES,
SR-FTIR

Language中文
Document Type学位论文
Identifierhttp://ir.iswc.ac.cn/handle/361005/8913
Collection水保所知识产出(1956---)
Recommended Citation
GB/T 7714
李 婷. 黄土丘陵区植被恢复过程中土壤有机碳 官能团变化的研究[D]. 北京. 中国科学院研究生院,2012.
Files in This Item:
File Name/Size DocType Version Access License
黄土丘陵区植被恢复过程中土壤有机碳官能团(1059KB)学位论文 开放获取CC BY-NC-SAApplication Full Text
Related Services
Recommend this item
Bookmark
Usage statistics
Export to Endnote
Google Scholar
Similar articles in Google Scholar
[李 婷]'s Articles
Baidu academic
Similar articles in Baidu academic
[李 婷]'s Articles
Bing Scholar
Similar articles in Bing Scholar
[李 婷]'s Articles
Terms of Use
No data!
Social Bookmark/Share
All comments (0)
No comment.
 

Items in the repository are protected by copyright, with all rights reserved, unless otherwise indicated.