| ACKNOWLEDGEMENT | 第9-17页 |
| ABSTRACT | 第17-19页 |
| 摘要 | 第20-22页 |
| CHAPTER 1 General Introduction and Review of Literature | 第22-32页 |
| 1.1 Heavy metals in the environment | 第23-24页 |
| 1.2 Bioavailability of heavy metals in the soil | 第24-25页 |
| 1.3 Uptake of heavy metals by food crops | 第25-26页 |
| 1.4 Health risks related to heavy metals | 第26-27页 |
| 1.5 Environmental quality standards for soils | 第27-28页 |
| 1.6 Heavy metals and soil microbial community | 第28-31页 |
| 1.7 Objectives of the study | 第31-32页 |
| CHAPTER 2 Cadmium Phytoavailability to Rice (Oryza sativa L.) Grown in Representative Chinese Soils. A Model toImprove Soil Environmental Quality Guidelines for Food Safety | 第32-48页 |
| 2.1 Introduction | 第32-33页 |
| 2.2 Materials and methods | 第33-36页 |
| 2.2.1 Soil collection and analysis | 第33-34页 |
| 2.2.2 Cd spiking | 第34页 |
| 2.2.3 Green house experiment | 第34-35页 |
| 2.2.4 Soil and rice grain analysis | 第35-36页 |
| 2.2.4.1 Grain sample collection and preparation | 第35页 |
| 2.2.4.2 Total Cd of soil and polished rice | 第35-36页 |
| 2.2.4.3 Mehlich-3-extractable Cd in soils | 第36页 |
| 2.2.5 Statistical analysis | 第36页 |
| 2.3 Results and discussion | 第36-48页 |
| 2.3.1 Characteristics of soils | 第36-38页 |
| 2.3.2 Mehlich-3-extractable Cd in soils after aging of 6 months | 第38页 |
| 2.3.3 Biomass yield of rice | 第38-41页 |
| 2.3.4 Accumulation of Cd in polished rice grain | 第41页 |
| 2.3.5 Relationship between Mehlich-3-extractable Cd in soils and grain Cd content | 第41-43页 |
| 2.3.6 Multiple regression model for predicting cadmium phytoavailability to polished rice | 第43-45页 |
| 2.3.7 Soil Cd thresholds for potential dietary toxicity in rice | 第45-48页 |
| CHAPTER 3 Phytoavailability of Cadmium (Cd) to Pak Choi (Brassica chinensis L.) Grown in Chinese Soils:A Model toEvaluate the Impact of Soil Cd Pollution on Potential Dietary Toxicity | 第48-68页 |
| 3.1 Introduction | 第48-50页 |
| 3.2 Materials and methods | 第50-53页 |
| 3.2.1 Ethics statement | 第50页 |
| 3.2.2 Soil collection and analysis | 第50页 |
| 3.2.3 Cadmium spiking and aging | 第50-51页 |
| 3.2.4 Containerized experiment | 第51页 |
| 3.2.5 Plant sample collection | 第51页 |
| 3.2.6 Total Cd of soil and plant | 第51-52页 |
| 3.2.7 Mehlich-3-extractable Cd in soils | 第52页 |
| 3.2.8 Quality control for Cd analysis | 第52页 |
| 3.2.9 Derivation soil Cd thresholds for potential dietary toxicity in Pak choi | 第52-53页 |
| 3.2.10 Statistical Analysis | 第53页 |
| 3.3 Results | 第53-60页 |
| 3.3.1 Characteristics of soils | 第53-54页 |
| 3.3.2 Mehlich-3-extractable Cd in soils after Aging of 1 Year | 第54页 |
| 3.3.3 Biomass yield of Pak choi | 第54页 |
| 3.3.4 Accumulation and distribution of cadmium in Pak choi | 第54-55页 |
| 3.3.5 Relationship between Mehlich-3-extractable Cd in soils and Pak choi Cd content | 第55页 |
| 3.3.6 Soil Cd thresholds for potential dietary toxicity in Pak choi | 第55-60页 |
| 3.4 Discussion | 第60-68页 |
| 3.4.1 Biomass yield of Pak choi | 第60-62页 |
| 3.4.2 Accumulation and distribution of cadmium in Pak choi | 第62页 |
| 3.4.3 Relationship between Mehlich-3-extractable Cd in soils and Pak choi Cd content | 第62-63页 |
| 3.4.4 Soil Cd thresholds for potential dietary toxicity in Pak choi | 第63-64页 |
| 3.4.5 Stepwise regression model for predicting Cd phytoavailability to Pak choi | 第64-68页 |
| CHAPTER 4 Lead Phytoavailability to Rice (Oiyza sativa L.) Grown in Representative Chinese Soils. A Model to ImproveSoil Environmental Quality Standards for Food Safety | 第68-85页 |
| 4.1 Introduction | 第68-70页 |
| 4.2 Materials and methods | 第70-73页 |
| 4.2.1 Soil collection and analysis | 第70页 |
| 4.2.2 Pb spiking | 第70页 |
| 4.2.3 Containerized experiment | 第70-71页 |
| 4.2.4 Soil and rice Pb analysis | 第71-73页 |
| 4.2.5 Extractable Pb in soils | 第73页 |
| 4.2.6 Statistical analysis | 第73页 |
| 4.3 Results | 第73-82页 |
| 4.3.1 Mehlich-3-extractable Pb in soils after aging of 6 months | 第73页 |
| 4.3.2 Accumulation and distribution of lead in rice | 第73-74页 |
| 4.3.3 Biomass yield of Rice | 第74-78页 |
| 4.3.4 Correlation between Pb concentration in rice and different forms of Soil Pb | 第78页 |
| 4.3.5 Soil Pb thresholds for potential dietary toxicity in rice | 第78-79页 |
| 4.3.6 Stepwise regression model for predicting Pb phytoavailability to Rice | 第79-82页 |
| 4.4 Discussion | 第82-85页 |
| CHAPTER 5 Lead Phytoavailability to Pak Choi (Brassiaca Chinensis L.) Grown on Representative Chinese Soils:A Modelfor Assessment of Soil and Food Safety | 第85-98页 |
| 5.1 Introduction | 第85-86页 |
| 5.2 Materials and methods | 第86-88页 |
| 5.2.1 Soil collection and analysis | 第86-87页 |
| 5.2.2 Lead spiking | 第87页 |
| 5.2.3 Pot experiment | 第87页 |
| 5.2.4 Soil and plant Pb analysis | 第87-88页 |
| 5.2.5 Extractable Pb in Soils | 第88页 |
| 5.2.6 Statistical analysis | 第88页 |
| 5.3 Results | 第88-95页 |
| 5.3.1 Mehlich-3-extractable Pb in soils after 1 year aging | 第88-90页 |
| 5.3.2 Distribution of Pb in Pak choi | 第90页 |
| 5.3.3 Biomass yield of Pak choi shoots | 第90页 |
| 5.3.4 Correlation between Pb content in edible Pak choi shoots and different forms of soil Pb | 第90-92页 |
| 5.3.5 Soil Pb thresholds for potential dietary toxicity in Pak choi shoots | 第92页 |
| 5.3.6 Stepwise regression model for predicting Pb phytoavailability to Pak choi | 第92-95页 |
| 5.4 Discussion | 第95-98页 |
| CHAPTER 6 Changes in Microbial Biomass and Community Structure due to Cd and Pb Contamination in Acid and AlkalineSoils Growing Rice | 第98-108页 |
| 6.1 Introduction | 第98-99页 |
| 6.2 Materials and methods | 第99-101页 |
| 6.2.1 Soil collection and analysis | 第99页 |
| 6.2.2 Soil spiking | 第99页 |
| 6.2.3 Pot experiment | 第99-100页 |
| 6.2.4 Microbial biomass carbon (MBC) | 第100页 |
| 6.2.5 PLFA extraction | 第100-101页 |
| 6.2.6 Dehydrogenase activity (DEH) | 第101页 |
| 6.2.7 Statistical analysis | 第101页 |
| 6.3 Results | 第101-105页 |
| 6.3.1 Effect of Cd and Pb on microbial biomass carbon (MBC) | 第101-102页 |
| 6.3.2 The microbial community pattern in soils with different Cd and Pb loading rates | 第102-104页 |
| 6.3.3 Dehydrogenase activity (DEH) | 第104-105页 |
| 6.4 Discussion | 第105-108页 |
| CHAPTER 7 Major Findings and Future Perspectives | 第108-110页 |
| 7.1 Major findings | 第108-109页 |
| 7.2 Future perspectives | 第109-110页 |
| References | 第110-127页 |
| List of Publications | 第127页 |
