Sources and Composition of Organic Carbon in Tropical River
发布时间：2024-02-02 14:34
河流输送的有机碳是全球碳循环的重要组成部分。它通过陆地和海洋储库中的再矿化和保存过程,对大气中CO2的平衡和控制格局起到了至关重要的作用。陆源有机物在陆海交互作用区(河口和海岸)的输运过程对当地和全球的环境扰动极为敏感。因此对这些区域中的陆源有机物特征的理解,往往有助于认识其控制源地的过程及预测其在海洋碳循环的潜在作用。全球气候变化引起的自然气候条件的变化(如超大洪水／台风或极端干旱)和全球人口增长导致的人为改变(如大坝建设,森林砍伐和密集农业)是影响陆地和水生环境中重要环境元素(如碳和氮)的生物地球化学循环的两个重要因素。热带地区是全球科学界的研究热点,因为这些地区的水生系统地理跨度大,在过去几十年中全球环境变化(降水变化和土地利用变化)对其影响巨大。研究这些地区的碳通量组成,将使我们更好地理解自然和人为过程对热带地区陆源有机物迁移和循环的影响。尽管在过去的二十年来,印度和中国这两个发展中国家普通经历了大规模的自然气候变化(如季风降水的减少和频发的极端台风事件)和人类活动改造(如土地利用格局的改变,流域上大坝的建设和人口的增长),然而印度和中国陆架边缘的热带地区却很少被研究。只有有限...
【文章页数】：239 页
【学位级别】：博士
【文章目录】：
摘要
Abstract
Abbreviations of analytical terms
Chapter Ⅰ:Introduction
1.1 Scientific background
1.2 Carbon cycling under changing global conditions
1.2.1 Factors influencing the composition of terrestrial OM
1.3 The conundrum of OC characteristics in tropical river systems
1.3.1 Information gap
1.4 River systems of peninsular India and Hainan Island
1.4.1 Tropical (peninsular) India
1.4.2 Tropical Hainan Island, China
1.4.3 Previous studies on rivers of tropical India and China
1.5 Approach, hypothesis and objectives
Chapter Ⅱ:Materials and methods
2.1 Description of the study area
2.1.1 West coast of India (WCI)
2.1.1.1 Geology of WCI river basins
2.1.1.2 Geomorphology, precipitation and fluvial load
2.1.1.3 Land use pattern along WCI
2.1.2 Zuari river system
2.1.2.1 Geology of ZRS
2.1.2.2 Land use pattern over ZRS
2.1.3 Godavari river system
2.1.3.1 Geology of Godavari river basin
2.1.3.2 Geomorphology, precipitation and fluvial load
2.1.3.3 Land use pattern over Godavari basin
2.1.4 Nandujiang/Nandu River (Hainan, China)
2.1.4.1 Geomorphology, precipitation and fluvial load
2.1.4.2 Land use pattern over NDR
2.2 Sample collection and pre-treatment
2.2.1 Plants and soil samples
2.2.2 Water samples and bottom sediments
2.2.3 Sample pre-treatments and in situ measurements
2.3 Analytical methods
2.3.1 Grain size analysis
2.3.2 Bulk chemical analysis (elementary contents, isotopes)
2.3.3 Instrument calibration
(ⅰ) CHNOS analyzer
(ⅱ) Finnigan EA 1112-Delta plus XP IRMS
2.3.4 Lignin phenols analysis
2.3.5 Instrument calibration
2.4 Data processing and statistics
2.4.1 Multivariate statistical analysis
2.4.2 Principal component analysis (PCA)
2.4.3 Cluster Analysis
Chapter Ⅲ:Organic matter characterization in relation to the land use change across the estuaries of west coast of India between 12°N and 24°N-Implication through elemental, isotopic and biomarker constrains of sediments
3.1 Introduction
3.2 Research methods
3.2.1 Characteristics of river systems across WCI
3.2.2 Sampling and analysis
3.2.3 Data treatment
3.3 Results
3.3.1 Elemental and isotopic properties
3.3.2 Lignin phenol yield and compositional ratios
3.3.3 Principal Component Analysis (PCA)
3.3.4 Quantification of sedimentary OMsources in WCI estuaries
3.3.5 Land use change and sedimentary OC
3.4 Discussion
3.4.1 Composition and origin of OM in WCI estuaries
3.4.2 Land use change and terrigenous OM composition
3.4.3 Impact on coastal and marine system of Arabian Sea
3.5 Summary
Chapter Ⅳ:Characteristics of plants and soil organic matter along the Western Ghats, India
4.1 Introduction
4.2 Sampling and chemical analysis
4.3 Results and Discussion
4.3.1 Bulk properties
4.3.2 Lignin phenols and ratios
4.3.3 Fates and implications
4.4 Summary
Chapter V :Factors controlling the spatial and seasonal distribution of organic matter alongthe dispersal pathway ofZuari river system— implication through multivariatestatistics
5.1 Introduction
5.2 Sampling and analysis
5.3 Results
5.3.1 Physicochemical properties
5.3.2 Bulk concentrations, elemental and isotopic ratios
5.3.3 Lignin phenols composition
5.3.4 Multivariate statistical results
5.3.5 Quantification of OMproportion
5.4 Discussion
5.4.1 Biogeochemistry of OM in ZRS
5.4.2 Potential contribution of OM sources in ZRS
5.4.3 Factors influencing the OM biogeochemistry in ZRS
5.5 Summary
Chapter Ⅳ:Spatial variability of organic matter composition in largest peninsular river system, Godavari (India)-Influence of damming and precipitation variability
6.1 Introduction
6.2 Sampling and data collection
6.3 Results
6.3.1 Variability of SWM and Sediment load in Godavari River
6.3.2 Bulk properties (OC, TN, C/N,δ13C and grain size)
6.3.3 Lignin phenols and indices
6.3.4 Statistical results
6.4 Discussion
6.4.1 OM composition and source in the Godavari river basin
6.4.2 OM sources in Godavari River
6.4.3 OC flux from the Godavari River
6.5 Summary
Chapter Ⅶ:Temporal variability of organic matter composition in Nandujiang (Nandu River)-Influence of extreme precipitation event
7.1 Introduction
7.2 Sampling and analysis
7.3 Results
7.3.1 Climatic and hydrologic conditions in Nandu River
7.3.2 Hydrographic characteristics
7.3.3 Bulk concentrations, elemental and isotopic ratios
7.3.4 Lignin phenols composition
7.3.5 Principal component analyses (PCA)
7.4 Discussion
7.4.1 Biogeochemistry of POM transported by NDR
7.4.2 Nature and provenance of POM in NDR
7.4.3 Factors affecting OM composition in NDR
7.5 Summary
Chapter Ⅷ:Conclusions and Directions for Future Research
8.1 General Conclusions
8.2 Chapter wise conclusions
8.3 Global significance and synthesis
8.4 Conceptual Model
8.5 Uncertainty and limitations
8.6 Future directions
References
Appendix
攻读博士学細间发表的论文
参加学术会议
Acknowledgements
本文编号：3892821
【文章页数】：239 页
【学位级别】：博士
【文章目录】：
摘要
Abstract
Abbreviations of analytical terms
Chapter Ⅰ:Introduction
1.1 Scientific background
1.2 Carbon cycling under changing global conditions
1.2.1 Factors influencing the composition of terrestrial OM
1.3 The conundrum of OC characteristics in tropical river systems
1.3.1 Information gap
1.4 River systems of peninsular India and Hainan Island
1.4.1 Tropical (peninsular) India
1.4.2 Tropical Hainan Island, China
1.4.3 Previous studies on rivers of tropical India and China
1.5 Approach, hypothesis and objectives
Chapter Ⅱ:Materials and methods
2.1 Description of the study area
2.1.1 West coast of India (WCI)
2.1.1.1 Geology of WCI river basins
2.1.1.2 Geomorphology, precipitation and fluvial load
2.1.1.3 Land use pattern along WCI
2.1.2 Zuari river system
2.1.2.1 Geology of ZRS
2.1.2.2 Land use pattern over ZRS
2.1.3 Godavari river system
2.1.3.1 Geology of Godavari river basin
2.1.3.2 Geomorphology, precipitation and fluvial load
2.1.3.3 Land use pattern over Godavari basin
2.1.4 Nandujiang/Nandu River (Hainan, China)
2.1.4.1 Geomorphology, precipitation and fluvial load
2.1.4.2 Land use pattern over NDR
2.2 Sample collection and pre-treatment
2.2.1 Plants and soil samples
2.2.2 Water samples and bottom sediments
2.2.3 Sample pre-treatments and in situ measurements
2.3 Analytical methods
2.3.1 Grain size analysis
2.3.2 Bulk chemical analysis (elementary contents, isotopes)
2.3.3 Instrument calibration
(ⅰ) CHNOS analyzer
(ⅱ) Finnigan EA 1112-Delta plus XP IRMS
2.3.4 Lignin phenols analysis
2.3.5 Instrument calibration
2.4 Data processing and statistics
2.4.1 Multivariate statistical analysis
2.4.2 Principal component analysis (PCA)
2.4.3 Cluster Analysis
Chapter Ⅲ:Organic matter characterization in relation to the land use change across the estuaries of west coast of India between 12°N and 24°N-Implication through elemental, isotopic and biomarker constrains of sediments
3.1 Introduction
3.2 Research methods
3.2.1 Characteristics of river systems across WCI
3.2.2 Sampling and analysis
3.2.3 Data treatment
3.3 Results
3.3.1 Elemental and isotopic properties
3.3.2 Lignin phenol yield and compositional ratios
3.3.3 Principal Component Analysis (PCA)
3.3.4 Quantification of sedimentary OMsources in WCI estuaries
3.3.5 Land use change and sedimentary OC
3.4 Discussion
3.4.1 Composition and origin of OM in WCI estuaries
3.4.2 Land use change and terrigenous OM composition
3.4.3 Impact on coastal and marine system of Arabian Sea
3.5 Summary
Chapter Ⅳ:Characteristics of plants and soil organic matter along the Western Ghats, India
4.1 Introduction
4.2 Sampling and chemical analysis
4.3 Results and Discussion
4.3.1 Bulk properties
4.3.2 Lignin phenols and ratios
4.3.3 Fates and implications
4.4 Summary
Chapter V :Factors controlling the spatial and seasonal distribution of organic matter alongthe dispersal pathway ofZuari river system— implication through multivariatestatistics
5.1 Introduction
5.2 Sampling and analysis
5.3 Results
5.3.1 Physicochemical properties
5.3.2 Bulk concentrations, elemental and isotopic ratios
5.3.3 Lignin phenols composition
5.3.4 Multivariate statistical results
5.3.5 Quantification of OMproportion
5.4 Discussion
5.4.1 Biogeochemistry of OM in ZRS
5.4.2 Potential contribution of OM sources in ZRS
5.4.3 Factors influencing the OM biogeochemistry in ZRS
5.5 Summary
Chapter Ⅳ:Spatial variability of organic matter composition in largest peninsular river system, Godavari (India)-Influence of damming and precipitation variability
6.1 Introduction
6.2 Sampling and data collection
6.3 Results
6.3.1 Variability of SWM and Sediment load in Godavari River
6.3.2 Bulk properties (OC, TN, C/N,δ13C and grain size)
6.3.3 Lignin phenols and indices
6.3.4 Statistical results
6.4 Discussion
6.4.1 OM composition and source in the Godavari river basin
6.4.2 OM sources in Godavari River
6.4.3 OC flux from the Godavari River
6.5 Summary
Chapter Ⅶ:Temporal variability of organic matter composition in Nandujiang (Nandu River)-Influence of extreme precipitation event
7.1 Introduction
7.2 Sampling and analysis
7.3 Results
7.3.1 Climatic and hydrologic conditions in Nandu River
7.3.2 Hydrographic characteristics
7.3.3 Bulk concentrations, elemental and isotopic ratios
7.3.4 Lignin phenols composition
7.3.5 Principal component analyses (PCA)
7.4 Discussion
7.4.1 Biogeochemistry of POM transported by NDR
7.4.2 Nature and provenance of POM in NDR
7.4.3 Factors affecting OM composition in NDR
7.5 Summary
Chapter Ⅷ:Conclusions and Directions for Future Research
8.1 General Conclusions
8.2 Chapter wise conclusions
8.3 Global significance and synthesis
8.4 Conceptual Model
8.5 Uncertainty and limitations
8.6 Future directions
References
Appendix
攻读博士学細间发表的论文
参加学术会议
Acknowledgements
本文编号：3892821
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