长期不同耕作措施对黄土高原半干旱区小麦豌豆轮作系统土壤微生物多样性和CO 2 排放的影响及机制
发布时间：2023-03-05 03:30
土壤管理措施可改变农田土壤微生物多样性和CO2排放,农田土壤微生物通过分解和矿化主要的土壤循环元素(C、N、P和S),从而影响土壤质量和肥力。土壤微生物还通过改变土壤呼吸与微生物对土壤有机质的分解速率从而影响地上生态系统中植物生长及CO2排放。本研究依托甘肃农业大学旱作农业综合实验站于2001年设计的长期定位试验,选取四个处理,即传统耕作(T),免耕(NT),传统耕作+秸秆还田(TS)和免耕+秸秆还田(NTS),于2016、2017和2018年研究了长期不同耕作措施下豌豆播前、花期与收后农田土壤微生物多样性与CO2排放的变化,并从土壤理化性质角度探讨耕作措施影响土壤微生物多样性与CO2排放的主要机制,主要研究结果如下:1.免耕秸秆还田和免耕提高了土壤微生物多样性。在0-10cm土层下,免耕秸秆还田增加了细菌16S rRNA OTUs的数量,免耕主要增加了古菌16S rRNA OTUs和真菌ITS OTUs的数量;播前、花期和收后时10-30 cm土层下非根际土壤细菌16S rRNA和真菌ITS数量较0-10 cm土层的增幅分别为1.2-8.3%和3.5-12.5%,而根际土壤细菌和真菌...
【文章页数】：191 页
【学位级别】：博士
【文章目录】：
摘要
Summary
List of Abbreviations
Introduction
Chapter 1 Literature Review
1.1 Soil ecosystem microbial community composition
1.2 Difference between rhizosphere and bulk soil microbial activity
1.3 Effects of tillage practices on soil microbial diversity
1.4 Effect of tillage practices on soil physical and chemical properties
1.5 Factors and underlying mechanisms driving soil microbial diversity
1.6 Factors and underlying mechanisms driving soil CO2 emission
1.7 Importance of conservation agriculture (CA)
1.8 Methods employed in the identification of soil microbes
Chapter 2 Materials and Methods
2.1 Study site description
2.2 Design of experiment
2.3 Research workflow
2.4 Soil sampling
2.5 Soil moisture and temperature
2.6 Soil chemical analysis
2.7 Carbon emission characteristics
2.7.1 Soil respiration monitoring and carbon emission calculation
2.7.2 Carbon emission efficiency calculation
2.8 Soil DNA extraction, amplification and sequencing
2.9 Data analysis
Chapter 3 Effect of long-term tillage practices on soil physical and chemical properties
3.1 Effect of tillage practices on soil physical properties
3.1.1 Effect of tillage practices on soil moisture
3.1.2 Effect of tillage practices on soil temperature
3.2 Effect of tillage practices on soil chemical properties
3.2.1 Effect of tillage practices on pre-sowing stage soil chemical properties
3.2.2 Effect of tillage practices on flowering stage soil chemical properties
3.2.3 Effect of tillage practices on pre-harvest stage soil chemical properties
3.3 Chapter summary
Chapter 4 Impact of different long-term tillage practices on soil archaeal, bacterial and fungal communities
4.1 Soil microbial community diversity as affected by tillage practices
4.1.1 Diversity of pre-sowing stage soil microbial community as affected by tillage practices
4.1.2 Diversity of flowering stage soil microbial community as affected by tillage practices
4.1.3 Diversity of pre-harvest stage soil microbial community as affected by tillage practices
4.2 Venn analysis of microbial OTUs abundance as affected by tillage practices
4.2.1 Venn analysis of pre-sowing stage microbial OTUs as affected by tillage practices
4.2.2 Venn analysis of flowering stage microbial OTUs as affected by tillage practices
4.2.3 Venn analysis of pre-harvest stage microbial OTUs as affected by tillage practices
4.3 PERMANOVA and ANOSIM of microbial communities as influenced by tillage practices
4.4 Soil microbial community taxa as affected by tillage practices
4.4.1 Pre-sowing stage phylum level soil microbial community as affected by tillage practices
4.4.2 Flowering stage phylum level soil microbial community as affected by tillage practices
4.4.3 Pre-harvest stage phylum level soil microbial community as affected by tillage practices
4.4.4 Pre-sowing stage Class and Genus level soil microbial community as affected by tillage practices
4.4.5 Flowering stage Class and Genus level soil microbial community as affected by tillage practices
4.4.6 Pre-harvest stage Class and Genus level soil microbial community as affected by tillage practices
4.5 Chapter summary
Chapter 5 Effect of long-term tillage practices on soil respiration and CO2 emission
5.1 Effect of tillage practices on soil respiration and CO2 emission
5.2 Effect of tillage practices on mean soil respiration and total carbon emission and carbon emission efficiency
5.3 Chapter summary
Chapter 6 Relationship between soil microbial diversity, soil physical and chemical properties, soil respiration, and CO2 emission
6.1 Mantel tests between soil microbial community composition and soil physical and chemical properties and CO2 emission
6.2 NMDS of soil microbial community, physical and chemical properties as affected by tillage practices
6.2.1 NMDS of pre-sowing stage soil microbial community and chemical properties as affected by tillage practices
6.2.2 NMDS of flowering stage soil microbial community and chemical properties as affected by tillage practices
6.2.3 NMDS of pre-harvest stage soil microbial community and chemical properties as affected by tillage practices
6.2.4 NMDS of flowering stage soil microbial community, soil physical properties, soil respiration and CO2 emission as affected by different tillage practices
6.2.5 NMDS of pre-harvest stage soil microbial community and soil physical properties as affected by tillage practices
6.3 Pearson correlation between soil microbial diversity, tillage and stubble effect, and chemical properties
6.3.1 Pearson correlation between pre-sowing stage soil microbial diversity, tillage and stubble effect, and chemical properties
6.3.2 Pearson correlation between flowering stage soil microbial diversity, tillage and stubblee ffect, respiration, total CO2 emission, physical and chemical properties
6.3.3 Pearson correlation between pre-harvest stage soil microbial diversity, respiration, total CO2 emission, tillage and stubble effect, physical and chemical properties
6.4 Principal component analysis of soil microbial diversity and physical and chemical properties as affected by different tillage practices
6.4.1 Principal component analysis of pre-sowing stage soil microbial diversity and chemical properties as affected by tillage practices
6.4.2 Principal component analysis of flowering stage soil microbial diversity, physical and chemical properties, soil respiration and CO2 emission as affected by tillage practices
6.4.3 Principal component analysis of pre-harvest stage soil microbial diversity, physical and chemical properties, soil respiration and CO2 emission as affected by tillage practices
6.5 Chapter summary
Chapter 7 Discussion and conclusions
7.1 Discussion
7.1.1 Soil microbial community composition as affected by tillage practices
7.1.2 Mechanisms underlying tillage practice effect on soil microbial community
7.1.3 Effect of tillage practices on soil on CO2 emission
7.1.4 Mechanisms underlying soil microbial community effect on CO2 emission
7.1.5 Relationship between microbial diversity and soil chemical properties
7.2 Conclusions
7.3 Recommendations for future research
References
Acknowledgements
导师简介
Personal Resume
本文编号：3755612
【文章页数】：191 页
【学位级别】：博士
【文章目录】：
摘要
Summary
List of Abbreviations
Introduction
Chapter 1 Literature Review
1.1 Soil ecosystem microbial community composition
1.2 Difference between rhizosphere and bulk soil microbial activity
1.3 Effects of tillage practices on soil microbial diversity
1.4 Effect of tillage practices on soil physical and chemical properties
1.5 Factors and underlying mechanisms driving soil microbial diversity
1.6 Factors and underlying mechanisms driving soil CO2 emission
1.7 Importance of conservation agriculture (CA)
1.8 Methods employed in the identification of soil microbes
Chapter 2 Materials and Methods
2.1 Study site description
2.2 Design of experiment
2.3 Research workflow
2.4 Soil sampling
2.5 Soil moisture and temperature
2.6 Soil chemical analysis
2.7 Carbon emission characteristics
2.7.1 Soil respiration monitoring and carbon emission calculation
2.7.2 Carbon emission efficiency calculation
2.8 Soil DNA extraction, amplification and sequencing
2.9 Data analysis
Chapter 3 Effect of long-term tillage practices on soil physical and chemical properties
3.1 Effect of tillage practices on soil physical properties
3.1.1 Effect of tillage practices on soil moisture
3.1.2 Effect of tillage practices on soil temperature
3.2 Effect of tillage practices on soil chemical properties
3.2.1 Effect of tillage practices on pre-sowing stage soil chemical properties
3.2.2 Effect of tillage practices on flowering stage soil chemical properties
3.2.3 Effect of tillage practices on pre-harvest stage soil chemical properties
3.3 Chapter summary
Chapter 4 Impact of different long-term tillage practices on soil archaeal, bacterial and fungal communities
4.1 Soil microbial community diversity as affected by tillage practices
4.1.1 Diversity of pre-sowing stage soil microbial community as affected by tillage practices
4.1.2 Diversity of flowering stage soil microbial community as affected by tillage practices
4.1.3 Diversity of pre-harvest stage soil microbial community as affected by tillage practices
4.2 Venn analysis of microbial OTUs abundance as affected by tillage practices
4.2.1 Venn analysis of pre-sowing stage microbial OTUs as affected by tillage practices
4.2.2 Venn analysis of flowering stage microbial OTUs as affected by tillage practices
4.2.3 Venn analysis of pre-harvest stage microbial OTUs as affected by tillage practices
4.3 PERMANOVA and ANOSIM of microbial communities as influenced by tillage practices
4.4 Soil microbial community taxa as affected by tillage practices
4.4.1 Pre-sowing stage phylum level soil microbial community as affected by tillage practices
4.4.2 Flowering stage phylum level soil microbial community as affected by tillage practices
4.4.3 Pre-harvest stage phylum level soil microbial community as affected by tillage practices
4.4.4 Pre-sowing stage Class and Genus level soil microbial community as affected by tillage practices
4.4.5 Flowering stage Class and Genus level soil microbial community as affected by tillage practices
4.4.6 Pre-harvest stage Class and Genus level soil microbial community as affected by tillage practices
4.5 Chapter summary
Chapter 5 Effect of long-term tillage practices on soil respiration and CO2 emission
5.1 Effect of tillage practices on soil respiration and CO2 emission
5.2 Effect of tillage practices on mean soil respiration and total carbon emission and carbon emission efficiency
5.3 Chapter summary
Chapter 6 Relationship between soil microbial diversity, soil physical and chemical properties, soil respiration, and CO2 emission
6.1 Mantel tests between soil microbial community composition and soil physical and chemical properties and CO2 emission
6.2 NMDS of soil microbial community, physical and chemical properties as affected by tillage practices
6.2.1 NMDS of pre-sowing stage soil microbial community and chemical properties as affected by tillage practices
6.2.2 NMDS of flowering stage soil microbial community and chemical properties as affected by tillage practices
6.2.3 NMDS of pre-harvest stage soil microbial community and chemical properties as affected by tillage practices
6.2.4 NMDS of flowering stage soil microbial community, soil physical properties, soil respiration and CO2 emission as affected by different tillage practices
6.2.5 NMDS of pre-harvest stage soil microbial community and soil physical properties as affected by tillage practices
6.3 Pearson correlation between soil microbial diversity, tillage and stubble effect, and chemical properties
6.3.1 Pearson correlation between pre-sowing stage soil microbial diversity, tillage and stubble effect, and chemical properties
6.3.2 Pearson correlation between flowering stage soil microbial diversity, tillage and stubblee ffect, respiration, total CO2 emission, physical and chemical properties
6.3.3 Pearson correlation between pre-harvest stage soil microbial diversity, respiration, total CO2 emission, tillage and stubble effect, physical and chemical properties
6.4 Principal component analysis of soil microbial diversity and physical and chemical properties as affected by different tillage practices
6.4.1 Principal component analysis of pre-sowing stage soil microbial diversity and chemical properties as affected by tillage practices
6.4.2 Principal component analysis of flowering stage soil microbial diversity, physical and chemical properties, soil respiration and CO2 emission as affected by tillage practices
6.4.3 Principal component analysis of pre-harvest stage soil microbial diversity, physical and chemical properties, soil respiration and CO2 emission as affected by tillage practices
6.5 Chapter summary
Chapter 7 Discussion and conclusions
7.1 Discussion
7.1.1 Soil microbial community composition as affected by tillage practices
7.1.2 Mechanisms underlying tillage practice effect on soil microbial community
7.1.3 Effect of tillage practices on soil on CO2 emission
7.1.4 Mechanisms underlying soil microbial community effect on CO2 emission
7.1.5 Relationship between microbial diversity and soil chemical properties
7.2 Conclusions
7.3 Recommendations for future research
References
Acknowledgements
导师简介
Personal Resume
本文编号：3755612
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