武夷山不同海拔植被土壤有机质化学结构表征及降解
发布时间：2021-05-11 06:33
水溶性有机碳是一种最活跃的土壤有机碳,它在全球碳循坏中起着极其重要的作用。然而,根据密度分组,土壤有机质又可分为轻组和重组两组分。本文通过紫外、荧光和傅立叶变换红外光谱来表征热水可提取有机质的化学结构特征。同步荧光光谱显示了热水可提取有机质中主要存在芳香性氨基酸,富里酸和具有高度共轭体系的聚环芳香结构。红外光谱表明热水可提取有机质中主要包含脂肪族的C-H键,芳香族的C=C键,以及碳水化合物中的C-O键三种官能团结构。针叶林土壤热水可提取有机质（0-10 cm土层）的芳香性,腐殖化指数（HIXem, HIXsyn）和荧光效率都明显高于其他三种植被类型,并且这四项光谱参数均随土壤深度的增加而减小。常绿阔叶林和亚高山矮曲林土壤中的热水可提取有机碳的生物降解程度较高,大约有20%的热水可提取有机碳被矿化,且热水可提取有机碳库的易变组分占到13-15%。然而,针叶林土壤的热水可提取有机碳最难被降解,其中只有12%的热水可提取有机碳被矿化。研究表明,较高的热水可提取有机碳的生物降解能力主要取决于较低的土壤C/N比,较低的芳香性和腐殖化程度,较低比例的酚类化合物含量,以及较高比例的亲水碳含量。高山草...
【文章来源】：南京林业大学江苏省
【文章页数】：88 页
【学位级别】：博士
【文章目录】：
Acknowledgements
摘要
Abstract
Chapter 1 Introduction
1 Soil organic matter pool
1.1 Soil organic matter resources
1.2 Composition and structure of soil organic matter
1.3 Labile and stabilized soil organic matter pools
1.4 Stabilization mechanisms of soil organic matter
1.5 Factors affecting the decomposition of soil organic matter
1.6 Effect of land-use change on soil organic carbon
2 Soil dissolved organic matter
2.1 Origins and compositions of dissolved organic matte
2.2 Dissolved organic matter extraction
2.3 Dissolved organic matter mineralization
2.4 Factors controlling dissolved organic matter mineralization
2.5 Analysis methods of dissolved organic matter
2.5.1 Isolation of dissolved organic matter
2.5.2 UV-vis absorption
2.5.3 Fluorescence spectroscopy
2.5.4 Fourier transform infrared spectroscopy
2.5.5 Nuclear magnetic resonance spectroscopy
2.5.6 Pyrolysis and related techniques
3 Light and heavy fractions of soil organic matter
4 Soil microbial biomass
5 Soil basal respiration
6 Soil metabolic quotient
Chapter 2 Site description and experimental design
1 Site description
2 Experimental designs
Chapter 3 Spectroscopic characterization of water extractable organic matter from soils under four different vegetation types along an elevation gradient
1 Introduction
2 Materials and methods
2.1 Soil sampling and analysis
2.2 Hot-water soluble organic matter extraction
2.3 Soil microbial biomass C
2.4 Soil basal respiration and metabolic quotient (qCO_2)
2.5 Spectroscopic analysis
2.6 Statistical analysis
3 Results and discussion
3.1 Soil properties
3.2 HWEOC, MBC and qCO_2
3.3 UV absorption of HWEOM
3.4 Fluorescence spectroscopic analysis
3.5 Fourier-transform infrared spectroscopic analysis
3.6 HWEOM spectroscopic properties in relation to soil properties and biological propertie
4 Conclusions
Chapter 4 Biodegradation and chemical characteristics of water extractable organic matter from soils under four different vegetation types along and elevation gradient
1 Introduction
2 Materials and methods
2.1 Hot-water soluble organic matter extraction
2.2 Incubation experiment
2.3 Analytical methods
2.4 Calculations and statistics
3 Results
3.1 Quantities and chemical characteristics of HWEOM
3.2 Dynamics of HWEOC biodegradation
3.3 HWEOC biodegradation in relation to its chemical characteristics
3.4 UV absorption and humification index changes during biodegradation
4 Discussion
5 Conclusions
Chapter 5 Light and heavy fractions of soil organic matter as related to altitude, vegetation and soil properties
1 Introduction
2 Material and methods
2.1 Soil sampling and analysis
2.2 Soil temperature and moisture
2.3 Litter and fine root biomass
2.4 Density separation
2.5 Statistical analysis
3 Results
3.1 Soil properties
3.2 Soil temperature and moisture, litter and fine root biomass, microbial biomass C
3.3 Carbon and nitrogen concentrations in density fractions
3.4 Contribution of the light and heavy fractions to SOM pool
3.5 Altitude, organism inputs and soil properties in relation to density fractions
4 Discussion
5 Conclusions
Chapter 6 Summary and Conclusions
References
详细摘要
本文编号：3180915
【文章来源】：南京林业大学江苏省
【文章页数】：88 页
【学位级别】：博士
【文章目录】：
Acknowledgements
摘要
Abstract
Chapter 1 Introduction
1 Soil organic matter pool
1.1 Soil organic matter resources
1.2 Composition and structure of soil organic matter
1.3 Labile and stabilized soil organic matter pools
1.4 Stabilization mechanisms of soil organic matter
1.5 Factors affecting the decomposition of soil organic matter
1.6 Effect of land-use change on soil organic carbon
2 Soil dissolved organic matter
2.1 Origins and compositions of dissolved organic matte
2.2 Dissolved organic matter extraction
2.3 Dissolved organic matter mineralization
2.4 Factors controlling dissolved organic matter mineralization
2.5 Analysis methods of dissolved organic matter
2.5.1 Isolation of dissolved organic matter
2.5.2 UV-vis absorption
2.5.3 Fluorescence spectroscopy
2.5.4 Fourier transform infrared spectroscopy
2.5.5 Nuclear magnetic resonance spectroscopy
2.5.6 Pyrolysis and related techniques
3 Light and heavy fractions of soil organic matter
4 Soil microbial biomass
5 Soil basal respiration
6 Soil metabolic quotient
Chapter 2 Site description and experimental design
1 Site description
2 Experimental designs
Chapter 3 Spectroscopic characterization of water extractable organic matter from soils under four different vegetation types along an elevation gradient
1 Introduction
2 Materials and methods
2.1 Soil sampling and analysis
2.2 Hot-water soluble organic matter extraction
2.3 Soil microbial biomass C
2.4 Soil basal respiration and metabolic quotient (qCO_2)
2.5 Spectroscopic analysis
2.6 Statistical analysis
3 Results and discussion
3.1 Soil properties
3.2 HWEOC, MBC and qCO_2
3.3 UV absorption of HWEOM
3.4 Fluorescence spectroscopic analysis
3.5 Fourier-transform infrared spectroscopic analysis
3.6 HWEOM spectroscopic properties in relation to soil properties and biological propertie
4 Conclusions
Chapter 4 Biodegradation and chemical characteristics of water extractable organic matter from soils under four different vegetation types along and elevation gradient
1 Introduction
2 Materials and methods
2.1 Hot-water soluble organic matter extraction
2.2 Incubation experiment
2.3 Analytical methods
2.4 Calculations and statistics
3 Results
3.1 Quantities and chemical characteristics of HWEOM
3.2 Dynamics of HWEOC biodegradation
3.3 HWEOC biodegradation in relation to its chemical characteristics
3.4 UV absorption and humification index changes during biodegradation
4 Discussion
5 Conclusions
Chapter 5 Light and heavy fractions of soil organic matter as related to altitude, vegetation and soil properties
1 Introduction
2 Material and methods
2.1 Soil sampling and analysis
2.2 Soil temperature and moisture
2.3 Litter and fine root biomass
2.4 Density separation
2.5 Statistical analysis
3 Results
3.1 Soil properties
3.2 Soil temperature and moisture, litter and fine root biomass, microbial biomass C
3.3 Carbon and nitrogen concentrations in density fractions
3.4 Contribution of the light and heavy fractions to SOM pool
3.5 Altitude, organism inputs and soil properties in relation to density fractions
4 Discussion
5 Conclusions
Chapter 6 Summary and Conclusions
References
详细摘要
本文编号：3180915
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