Chapter 1 Introduction
1.1 Research background and purpose
1.2 Domestic and foreign research progress
1.2.1 The concept of heavy metals and their toxic performance
1.2.2 The source of heavy metal pollution in agricultural soil around the globe
1.2.3 Integrated GIS and multivariate statistical analysis for assessment of heavy metal soil contamination
1.2.4 The effect of soil physicochemical properties on heavy metals
1.2.5 Speciation of heavy metals in soils
1.2.6 Soil microbial community in metal mining and smelting area
1.3 Research content and technical route
1.3.1 Main content
1.3.2 Technical route
Chapter 2 Spatial Distribution, Risk Assessment and Source Identification of Toxic Heavy Metals in the Agricultural Soil around a Pb/Zn Mining and Smelting Area in Southwest China
2.1 Materials and methods
2.1.1 Study area
2.1.2 Sample collection and chemical analysis
2.1.3 Assessment methods of metals pollution
2.1.4 Data process and statistics
2.2 Results and discussion
2.2.1 Descriptive statistics
2.2.2 Assessment of the metals contamination
2.2.3 Spatial distribution of metals, pH and pollution degree
2.2.4 Vertical distribution of metals
2.2.5 Correlations of metals and pH
2.2.6 Source identification using PCA and CA
2.3 Conclusions
Chapter 3 Characterization of Heavy Metals and Physicochemical properties and their interrelationship in Soils under Different Land Use Patterns around Pb/Zn Mining and Smelting Area
3.1 Materials and methods
3.1.1 Study area
3.1.2 Sample collection and treatments
3.1.3 Chemical analysis
3.1.4 Data analysis and processing
3.2 Results and discussion
3.2.1 Differences in soil physicochemical properties under different land use patterns
3.2.2 Characteristics and sources of heavy metal content in soils under different land use patterns
3.2.3 Effects of physicochemical properties on heavy metals in soil under different land use patterns
3.3 Conclusions
Chapter 4 Geochemical Fraction of Heavy Metals in Soil under Different Land Use patterns in Pb/Zn Mining and Smelting Area
4.1 Materials and methods
4.1.1 Main equipment and instruments
4.1.2 Experimental reagent
4.1.3 Experimental procedure
4.1.4 Data analysis and processing
4.2 Results and discussion
4.2.1 Geochemical fraction of Cd in soil of different regions under different land use patterns
4.2.2 Geochemical fraction of Hg in soil of different regions under different land use patterns
4.2.3 Geochemical fraction of As in soil of different regions under different land use patterns
4.2.4 Geochemical fraction of Pb in soil of different regions under different land use patterns
4.2.5 Geochemical fraction of Cr in soil of different regions under different land use patterns
4.2.6 Geochemical fraction of Cu in soil of different regions under different land use patterns
4.2.7 Geochemical fraction of Zn in soil of different regions under different land use patterns
4.2.8 Geochemical fraction of Ni in soil of different regions under different land use patterns
4.3 Conclusions
Chapter 5 The Effect of Soil Physicochemical Properties and Heavy Metals on Bacterial Community under Different Land Use Types in Pb/Zn Mining and Smelting Area
5.1 Materials and methods
5.1.1 DNA extraction and PCR amplification
5.1.2 Illumina MiSeq sequencing
5.1.3 Processing of sequencing data
5.1.4 Data analysis
5.2 Results and discussion
5.2.1 Abundance andα-diversity of bacterial communities of soils under different land use types
5.2.2 The structure of the bacterial communities of soils under different land use on phylum level
5.2.3 Microbial communities correspond to different land use types
5.2.4 Relationship between soil physicochemical properties and bacterial taxa under different land use types
5.2.5 Relationship between heavy metals and bacterial taxa under different land use types
5.3 Conclusions
Chapter 6 Conclusions and Prospects
6.1 Conclusions
6.2 Prospects
参考文献
Appendix
致谢
声明
