| 摘要 | 第1-7页 |
| Abstract | 第7-14页 |
| CHAPTER Ⅰ | 第14-23页 |
| ·Introduction | 第14-15页 |
| ·Literature Review | 第15-22页 |
| ·Objectives | 第22-23页 |
| CHAPTER II MATERIALS AND METHODS | 第23-37页 |
| ·Study area | 第23-24页 |
| ·Sampling Methodology | 第24-26页 |
| ·Methods for SLCH calculation | 第26-27页 |
| ·Soil loss value per unit of crop mass | 第26页 |
| ·Total soil loss per harvest for a given crop on area-unit basis (SLCHcrop)/Crop-specific SLCH | 第26页 |
| ·Plant Specific SLCH | 第26页 |
| ·Mean annual SLCH rate | 第26-27页 |
| ·Nutrients and SOM loss (expressed on elemental basis) estimated using the following equation | 第27页 |
| ·Soil particle size analysis (sand , silt, clay) Hydrometer method | 第27-29页 |
| ·Scope | 第27页 |
| ·Principle | 第27页 |
| ·Special apparatus | 第27页 |
| ·Reagents | 第27页 |
| ·Sample preparation | 第27-28页 |
| ·Calculation of Soil classification | 第28-29页 |
| ·Soil pH measurement | 第29-30页 |
| ·(soil:water ratio of 1:25) Soil reaction committee | 第29-30页 |
| ·Maintenance of electrode: | 第30页 |
| ·Standard buffer solution | 第30页 |
| ·Comments and suggestions | 第30页 |
| ·Bulk density and soil water content (SWC) measurement | 第30-31页 |
| ·Procedure and Calculation | 第30-31页 |
| ·Determination of Soil Water Content (SWC) by oven-drying (standard) method | 第31页 |
| ·Calculation | 第31页 |
| ·Available P (Modified olsen pH> 6.5) (1:20) | 第31-32页 |
| ·Procedure | 第31-32页 |
| ·P standard solution | 第32页 |
| ·Working standard | 第32页 |
| ·Total N (Modified Micreo Kjheldhal) method | 第32-34页 |
| ·Procedure | 第32-33页 |
| ·Strength of H2SO4 Preparation | 第33页 |
| ·Chemicals and Reagents for total N | 第33-34页 |
| ·Soil Organic Carbon (SOC) (Nelson and Sommers, 1982,wet combustion method) | 第34-35页 |
| ·Procedure | 第34页 |
| ·Calculation | 第34-35页 |
| ·Available Nitrogen, Con-way method | 第35页 |
| ·Available potassium (K) (Flame photometer method) | 第35-37页 |
| ·Apparatus | 第35-36页 |
| ·Reagents | 第36页 |
| ·Procedure | 第36页 |
| ·Calculation | 第36-37页 |
| CHAPTER III RESULTS AND DISCUSSION | 第37-54页 |
| ·Descriptive statistics of SLCH variables for sweet potato harvesting for whole study | 第37页 |
| ·Descriptive statistics of SLCH variables for sugar beet harvesting in whole study | 第37-38页 |
| ·Descriptive statistics of SLCH variables for potato harvesting in whole study Overall Discussion | 第38-40页 |
| ·Gravimetric soil moisture content (GMC) at the harvest time and soil texture for every plot where sweet potato was harvested and mean, median, standard deviation, maximum and minimum for the whole study | 第40页 |
| ·Gravimetric soil moisture content (GMC) at the harvest time and soil texture for every plot where sugar beet was harvested and mean, median, standard deviation, maximum and minimum for the whole study | 第40-41页 |
| ·Gravimetric soil moisture content (GMC) at the harvest time and soil texture for every plot wherepotato was harvested and mean, median, standard deviation, maximum and minimum for the whole study Overall Discussion | 第41-43页 |
| ·Regression equation between SLCH variables for sweet potato, GMC%, soil texture, average root mass (Mcrop/p) (g/tuber), plant density (PD) (tubers/ha) and crop yield (Mcy)(Mg/ha) with indication of the coefficient of determination (R2) and the signific | 第43-44页 |
| ·Pearson correlation coefficients between the SLCH variables for sugar beet, GMC,soil texture, average root mass (Mcrop/p), plant density (PD) and crop yield (Mcy) | 第44页 |
| ·Regression equations between SLCHspec (Mg/Mg) and SLCHspec/p(g) for sugar beet and GMC,soil texture,average root mass,plant density and crop yield with indication of coefficient of determination (R2) and the significance level(p) | 第44页 |
| ·Spearman correlation coefficients between the SLCHvariables for potato, GMC, soil texture, average tuber mass (Mcrop/p), tuber density (PD) and crop yield (Mcy) | 第44-45页 |
| ·Regression equations between SLCHspec (Mg/Mg) and SLCHspec/p(g) for potato and GMC,soil texture,average root mass,plant density and crop yield with indication of coefficient of determination (R2) and the significance level(p) Overall Discussion | 第45-48页 |
| ·Nutrients and soil organic matter (SOM) losses (mg/ha/harvest) due to SLCH through crop harvesting SLCHcrop (mg/ha/harvest) for the whole study Discussion | 第48-52页 |
| ·Regression equation between SLCH variables for sweet potato, and total nitrogen (TN),available nitrogen(AN),available phosphorous(AP),available potassium(K) and soil organic matter(SOM) with indication of the coefficient of determination (R2) and the | 第49-52页 |
| ·Comparison of SLCH data between (Uganda), North east China and North China under same harvesting method Discussion | 第52-53页 |
| ·Overall discussion of relative importance of SLCH, nutrients and soil organic matter losses in contrast to other erosion results | 第53-54页 |
| CONCLUSION | 第54-56页 |
| REFERENCES | 第56-60页 |
| ACKNOWLEDGEMENTS | 第60-62页 |
| Work Experience in China from 2009 to 2012 | 第62-63页 |
| CV | 第63页 |
