| Abstract | 第6-9页 |
| Chinese abstract | 第10-13页 |
| Chapter I Introduction | 第13-36页 |
| 1.1 Cadmium pollution | 第13-20页 |
| 1.1.1 Impacts on humans | 第16-18页 |
| 1.1.2 Impacts on the plants | 第18页 |
| 1.1.3 Cd versus other heavy metals | 第18-20页 |
| 1.2 Biochar & crop straws role to bio availabilities of heavy metals | 第20-22页 |
| 1.3 Phytoremediation in Cd contaminated soils | 第22-34页 |
| 1.3.1 Phytoremediation techniques using chelating agents | 第24-26页 |
| 1.3.2 Phytoremediation and improving phytoextraction; potential for hyper andnon-hyper accumulator plant species on contaminated soil | 第26-30页 |
| 1.3.3 Phytoextraction | 第30-31页 |
| 1.3.4 Affecting phytoextraction | 第31-34页 |
| 1.4 Aims of study | 第34-36页 |
| Chapter II Material and Methods | 第36-43页 |
| 2.1 Plant and chelators used in this present study | 第36-37页 |
| 2.2 Soil collection and determination of Cd in soil and plant samples | 第37-38页 |
| 2.3 Sample prepration for FTIR specroscopy | 第38页 |
| 2.4 Growth parameters | 第38-39页 |
| 2.5 Microbial miomass (MBC) and dissolved organic carbon (DOC) | 第39页 |
| 2.6 Antioxydant enzymes extraction | 第39-40页 |
| 2.7 Chlorophylleand protien content | 第40页 |
| 2.8 Phytoextraction efficiency factors of plant | 第40-43页 |
| Chapter III Enhanced accumulation of Cd in castor (ricinus communis l.) by soil- appliedchelators | 第43-57页 |
| 3.1 Introduction | 第43-44页 |
| 3.2 Material and methods | 第44-45页 |
| 3.3 Results | 第45-54页 |
| 3.3.1 Plant Height (cm) | 第45-46页 |
| 3.3.2 Dry biomass production | 第46-47页 |
| 3.3.3 Effects of chelators on the accumulation of Cd uptake in soil | 第47-48页 |
| 3.3.4 Effects of the chelators on the Cd concentrations of castor plant tissue | 第48-49页 |
| 3.3.5 Chemical characterization of chelators in metal polluted soil | 第49-51页 |
| 3.3.6 Phytoremediation potential | 第51-54页 |
| 3.4 Discussion | 第54-56页 |
| 3.5 Conclusions | 第56-57页 |
| Chapter IV Synthetic chelating agents and metal availability in Cd polluted and non - polluted agricultural soil | 第57-70页 |
| 4.1 Introduction | 第57-59页 |
| 4.2 Material & Methods | 第59-61页 |
| 4.3 Statistical analyses | 第61-62页 |
| 4.4 Results and Discussion | 第62-69页 |
| 4.4.1 Concentrations of Cd and chelating agents in the Cd-polluted and non-polluted soils | 第62-63页 |
| 4.4.2 Chemical characterization of chelators in metal polluted soil | 第63-64页 |
| 4.4.3 To evaluate the microbial biomass carbon (MBC) in polluted and non-polluted soil. | 第64-65页 |
| 4.4.4 To assess the dissolved organic carbon (DOC) in polluted and non-polluted soil | 第65-66页 |
| 4.4.5 Phytoextraction potential in castor plant in Cd polluted and non-polluted soil | 第66-68页 |
| 4.4.6 Interaction between soil microbial carbon and available metal in Cd polluted soil | 第68-69页 |
| 4.5 Conclusions | 第69-70页 |
| Chapter V To evaluate the antioxidant enzymes using castor (Ricinus Communis L.) plant under cadmium stress | 第70-80页 |
| 5.1 Introduction | 第70-72页 |
| 5.2 Material and Methods | 第72-73页 |
| 5.3 Results | 第73-77页 |
| 5.4 Discussion | 第77-79页 |
| 5.5 Conclusions | 第79-80页 |
| Chapter VI The effects of rice straw biochar on Cd bioavailability and plant accumulationin Cd polluted soil | 第80-91页 |
| 6.1 Introduction | 第80-81页 |
| 6.2 Materials and methods | 第81-84页 |
| 6.3 Results and Discussion | 第84-89页 |
| 6.4 Conclusion | 第89-91页 |
| Chapter VII Concluding remarks, innovations and future perceptions | 第91-96页 |
| 7.1 Summary | 第91-93页 |
| 7.2 Principal novelty (chelators, biochar and enzyme activity) | 第93-94页 |
| 7.3 Future perspectives | 第94-96页 |
| References | 第96-112页 |
| Acknowledgement | 第112-114页 |
| Appendix | 第114-118页 |
