| Abstract | 第13-15页 |
| 摘要 | 第16-19页 |
| List of abbreviations | 第19-21页 |
| Chapter Ⅰ BACKGROUND AND REVIEW OF LITERATURE | 第21-43页 |
| 1. Heavy metal as an environmental pollutant | 第21-43页 |
| 1.1 Sources of heavy metals | 第21-23页 |
| 1.2 Cadmium pollution in soil | 第23-28页 |
| 1.2.1 Forms and chemistry of Cd in soil | 第25-26页 |
| 1.2.2 Effect of Cd on human and plants | 第26-27页 |
| 1.2.3 Factors affecting on mobility and bioavailability of Cd | 第27-28页 |
| 1.2.3.1 pH | 第27页 |
| 1.2.3.2 Cation exchange Capacity | 第27-28页 |
| 1.2.3.3 Organic matter | 第28页 |
| 1.2.3.4 Soil texture and clay content | 第28页 |
| 1.3 Remediation of contaminated soils | 第28-39页 |
| 1.3.1 Immobilization | 第29-31页 |
| 1.3.2 Immobilizing material | 第31-33页 |
| 1.3.2.1 Biochar | 第31-32页 |
| 1.3.2.2 Effect of biochar on Cd immobilization | 第32-33页 |
| 1.3.2.3 Mechanism of biochar interaction with cadmium | 第33页 |
| 1.3.3 Rock phosphate (RP) | 第33-37页 |
| 1.3.3.1 Phosphate induce heavy metal immobilization | 第34-36页 |
| 1.3.3.2 Mechanism of phosphate on Cd immobilization | 第36-37页 |
| 1.3.4 Zeolite | 第37-39页 |
| 1.3.4.1 Zeolite induce heavy metal immobilization | 第38-39页 |
| 1.3.4.2 Cadmium immobilization mechanism by zeolite | 第39页 |
| 1.4 Challenges and objectives | 第39-43页 |
| 1.4.1 Challenges | 第39-40页 |
| 1.4.2 Research gap | 第40-41页 |
| 1.4.3 Objectives | 第41-43页 |
| Chapter Ⅱ | 第43-48页 |
| 2.1 Materials and methods | 第43-44页 |
| 2.2 Biochar production and other immobilizing materials | 第44-45页 |
| 2.3 Sequential extraction procedure (BCR) | 第45页 |
| 2.4 Toxicity characteristic leaching procedure (TCLP) | 第45页 |
| 2.5 Ammonium nitrate extraction | 第45-46页 |
| 2.6 CaCl_2-single extraction | 第46页 |
| 2.7 Simple bioaccessibility extraction test (SBET) | 第46页 |
| 2.8 Bioavailability risk index (BARI) | 第46-48页 |
| CHAPTER Ⅲ CADMIUM IMMOBILIZATION POTENTIAL OF RICE STRAW-DERIVEDBIOCHAR,ZEOLITE AND ROCK PHOSPHATE:EXTRACTION TECHNIQUESAND ADSORPTION MECHANISM | 第48-65页 |
| 3.1 Introduction | 第48-49页 |
| 3.2 Materials and methods | 第49-51页 |
| 3.2.1 Soil characterization | 第49页 |
| 3.2.2 Biochar production and other immobilization material | 第49-50页 |
| 3.2.3 Incubation experiments | 第50页 |
| 3.2.4 Batch adsorption study of incubated soil | 第50页 |
| 3.2.5 Zeta potential determination | 第50-51页 |
| 3.2.6 Statistical analysis | 第51页 |
| 3.3 Results | 第51-55页 |
| 3.3.1 Soil pH changes after application of amendments | 第51-52页 |
| 3.3.2 BCR fraction of soil Cd after incubation | 第52-53页 |
| 3.3.3 TCLP and ammonium nitrate extractable Cd | 第53-54页 |
| 3.3.4 Zeta potential | 第54页 |
| 3.3.5 Isotherm of cadmium adsorption by amendments addition | 第54-55页 |
| 3.4 Discussion | 第55-64页 |
| 3.4.1 How different soil amendments changes soil pH | 第55-56页 |
| 3.4.2 Impact of amendments on Cd fractions | 第56-58页 |
| 3.4.3 Impact of amendments on Cd solubility and bioavailability | 第58-60页 |
| 3.4.4 Adsorption mechanism of Cd by stabilizers-amended soil | 第60-64页 |
| 3.5 Conclusion | 第64-65页 |
| CHAPTER Ⅳ CADMIUM MOBILITY, UPTAKE AND ANTIOXIDITAVE RESPONSE OF WATERSPINACH (Ipomoea Aquatic) UNDER RICE STRAW BIOCHAR, ZEOLITE ANDROCK PHOSPHATE AS AMENDMENTS | 第65-84页 |
| 4.1 Introduction | 第65-67页 |
| 4.2 Materials and methods | 第67-69页 |
| 4.2.1 Soil characterization | 第67页 |
| 4.2.2 Biochar production and other immobilization materials | 第67页 |
| 4.2.3 Pot experiments | 第67-68页 |
| 4.2.4 Soil Cd determination | 第68页 |
| 4.2.5 Bio-concentration,translocation and extraction coefficient factors | 第68页 |
| 4.2.6 Plant enzymatic activities and chlorophyll contents | 第68-69页 |
| 4.2.7 Statistical analysis | 第69页 |
| 4.3 Results | 第69-76页 |
| 4.3.1 Changes of soil pH and EC with addition of amendments | 第69-70页 |
| 4.3.2 Effect of amendments on Cd solubility | 第70-71页 |
| 4.3.3 Effect of amendments on Cd uptake by water spinach | 第71-72页 |
| 4.3.4 Bio-concentration and translocation and extraction coefficient factors | 第72-73页 |
| 4.3.5 Effect of amendments on plant growth and biochemical activities | 第73-76页 |
| 4.4 Discussion | 第76-82页 |
| 4.4.1 Mechanism of amendments on Cd immobilization | 第76-78页 |
| 4.4.2 Amendments effect on Cd uptake by plant | 第78-79页 |
| 4.4.3 Amendments effect on plant growth | 第79-80页 |
| 4.4.4 Bio-concentration and translocation and extraction concentration factors | 第80-81页 |
| 4.4.5 Amendments effect on plant biochemical activities | 第81-82页 |
| 4.5 Conclusion | 第82-84页 |
| CHAPTER Ⅴ EFFECT OF VARIOUS TYPES OF BIOCHAR ON Cd MOBILITY,BIOAVAILABILITY TO CHINESE CABBAGE, AND BIOCHEMICAL PROPERTIESIN CONTAMINATED SOIL | 第84-102页 |
| 5.1 Introduction | 第84-85页 |
| 5.2 Materials and methods | 第85-87页 |
| 5.2.1 Soils and biochar | 第85页 |
| 5.2.2 Pot experiment | 第85-86页 |
| 5.2.3 Soil chemical analysis | 第86页 |
| 5.2.4 Sequential extraction | 第86页 |
| 5.2.5 Soil bioaccessibility (SBET) technique | 第86页 |
| 5.2.6 Soil biochemical analysis | 第86-87页 |
| 5.2.7 Plant analysis | 第87页 |
| 5.3 Results | 第87-95页 |
| 5.3.1 Effect of biochar on soil chemical properties | 第87-88页 |
| 5.3.2 Effect of amendments on soil Cd fractions | 第88-89页 |
| 5.3.3 Effect of amendments on Cd solubility | 第89-91页 |
| 5.3.4 Effect of biochar on Cd bioaccessibility | 第91页 |
| 5.3.5 Biochar changes soil biochemical properties | 第91-92页 |
| 5.3.6 Cd uptake and translocation factor | 第92-94页 |
| 5.3.7 Effect on dry biomass and essential elements accumulation | 第94-95页 |
| 5.4 Discussion | 第95-100页 |
| 5.4.1 Biochar induce changes in soil chemical properties | 第95-96页 |
| 5.4.2 Biochar changes soil Cd fraction | 第96-98页 |
| 5.4.3 Effect of biochar on soil biochemical properties | 第98-99页 |
| 5.4.4 Cd uptake and plant growth | 第99-100页 |
| 5.5 Conclusions | 第100-102页 |
| CHAPTER Ⅵ COMPARING THE ADSORPTION MECHANISM OF CADMIUM (Cd) BY RICESTRAW PRISTINE AND KOH MODIFIED BIOCHAR | 第102-116页 |
| 6.1. Introduction | 第102-103页 |
| 6.2. Materials and methods | 第103-105页 |
| 6.2.1. Biochar production | 第103页 |
| 6.2.2. Biochar modification by KOH | 第103-104页 |
| 6.2.3. Batch adsorption of Cd by biochar | 第104页 |
| 6.2.4. Effect of pH on Cd adsorption | 第104页 |
| 6.2.5. Zeta potential measurement | 第104-105页 |
| 6.2.6. Product characterization | 第105页 |
| 6.2.7. Quality control | 第105页 |
| 6.3. Results and discussion | 第105-115页 |
| 6.3.1. Effect of solution pH on Cd removal | 第105-107页 |
| 6.3.2 Adsorption isotherm | 第107-110页 |
| 6.3.3. Cd adsorption mechanism | 第110-115页 |
| 6.4 CONCLUSION | 第115-116页 |
| CHAPTER Ⅶ IMMOBILIZATION OF CADMIUM WITH RICE STRAW DERIVED BIOCHARAND ITS MODIFICATION WITH KOH IN HIGHLY CONTAMINATED SOIL | 第116-131页 |
| 7.1. Introduction | 第116-117页 |
| 7.2 Materials and methods | 第117-118页 |
| 7.2.1 Sampling site and soil collection | 第117页 |
| 7.2.2 Biochar production and Biochar modiHcation | 第117页 |
| 7.2.3 Biochar characterization | 第117页 |
| 7.2.4 Incubation experiment | 第117-118页 |
| 7.2.5 Cd sequential extraction | 第118页 |
| 7.2.6 Extraction of soil Cd with NH_4NO_3 and TCLP | 第118页 |
| 7.2.7 Bioaccessibility and bioavailability risk index | 第118页 |
| 7.2.8 Statistical analysis | 第118页 |
| 7.3 Results | 第118-125页 |
| 7.3.1 Characteristics of biochar | 第118-119页 |
| 7.3.2 Biochar induces changes in soil properties | 第119-121页 |
| 7.3.3 Effect of amendments on Cd solubility | 第121-123页 |
| 7.3.4 Amendments effect on Cd fractionation | 第123-124页 |
| 7.3.5 Effect of amendments on Cd SBET and BARI test | 第124-125页 |
| 7.4 Discussion | 第125-130页 |
| 7.4.1 Effect of amendments on soil chemical properties | 第125-127页 |
| 7.4.2 Effect of amendments on Cd geochemical fractionation | 第127-128页 |
| 7.4.3 Effect of amendments on Cd bio-accessibility | 第128-129页 |
| 7.4.4 Cd immobilization mechanism by biochar and KOH modified biochar | 第129-130页 |
| 7.5 Conclusion | 第130-131页 |
| CHAPTER Ⅷ CONCLUDING REMARKS,NOVELTIES AND FUTURE PERSPECTIVES | 第131-135页 |
| 8.1 General summarising results | 第131-133页 |
| 8.2 Novelities | 第133页 |
| 8.3 Future Perspectives | 第133-134页 |
| 8.4 Economic valuation of the biochar application | 第134-135页 |
| REFERENCE | 第135-152页 |
| ACKNOWLEDGEMENT | 第152-154页 |
| LIST OF PUBLICATION | 第154页 |
