| Acknowledgements | 第1-4页 |
| Abstract | 第4-6页 |
| 摘要 | 第6-10页 |
| 1 Introduction | 第10-18页 |
| ·Carbon cycling and carbon missing sink | 第10-11页 |
| ·Purpose and significance on carbon study | 第11-12页 |
| ·Researches over soil labile organic carbon | 第12-13页 |
| ·Methods on SLOC sdudy | 第13-16页 |
| ·Major regulating factors of SLOC | 第16-18页 |
| ·Climate change | 第16-17页 |
| ·Forest type | 第17-18页 |
| 2 Materials and methods | 第18-24页 |
| ·Natural site condition | 第18-19页 |
| ·Site design | 第19页 |
| ·Methods | 第19-24页 |
| ·Soil sampling and disposal | 第19-20页 |
| ·Microbially available carbon measurement | 第20页 |
| ·Microbial biomass carbon measurement | 第20-21页 |
| ·Readily oxidation carbon measurement | 第21-22页 |
| ·Water-solubale organic carbon measurement | 第22页 |
| ·Soil respiration measurement | 第22页 |
| ·Fine root biomass measurement | 第22页 |
| ·Litter fall biomass measurement | 第22-23页 |
| ·Soil chemical and physical properties measurement | 第23页 |
| ·Data analysis | 第23-24页 |
| 3 Results | 第24-44页 |
| ·Microbially available carbon | 第24-33页 |
| ·MAC emission during sequential incubation cycles | 第24-25页 |
| ·Estimation of MAC turnover rates(k)and total MAC | 第25-26页 |
| ·Seasonal variation of MAC | 第26-31页 |
| ·Characteristics of MAC's seasonal variation in four sites | 第26-27页 |
| ·Relationships of seasonal variation of MAC with soil temperature & moisture,FRB and LFB | 第27-31页 |
| ·Relationship of seasonal variation between MAC and soil moisture | 第27-28页 |
| ·Relationship of seasonal variation between MAC and soil temperature | 第28-29页 |
| ·The 3-D relationship among MAC,soil moisture,soil temperature | 第29-31页 |
| ·Relationships of seasonal variation of MAC and FRB,LFB | 第31页 |
| ·Correlations of MAC with TOC,FRB,soil moisture & temperature,soil respiration,LFB,TN | 第31-33页 |
| ·Microbial biomass carbon | 第33-36页 |
| ·Spatial variation of MBC | 第33-34页 |
| ·Seasonal variation of MBC | 第34-35页 |
| ·Characteristics of MBC's seasonal variation in four sites | 第34页 |
| ·Relationships of seasonal variation of MBC with soil moisture & temperature | 第34-35页 |
| ·Relationships of seasonal variation of MBC with FRB and LFB | 第35页 |
| ·Correlations of MBC with TOC,FRB,soil moisture & temperature,soil respiration,LFB,TN | 第35-36页 |
| ·Readily oxidation carbon | 第36-39页 |
| ·Spatial variation of ROC | 第36-37页 |
| ·Correlations of ROC with TOC,FRB,soil moiture & temperature,soil respiration,LFB,TN | 第37-39页 |
| ·Water-soluble organic carbon | 第39-42页 |
| ·Spatial variation of WSOC | 第39-40页 |
| ·Correlations of ROC with TOC,FRB,soil moiture,soil respiration,LFB,TN,TS,pH | 第40-42页 |
| ·Relationships among MAC,MBC,ROC,WSOC and TOC | 第42-44页 |
| 4 Discussion | 第44-51页 |
| ·Spatial variation of labile organic carbon | 第44-46页 |
| ·Relationships between labile organic carbon and regulating factors | 第46-47页 |
| ·Relationships among MAC,MBC,ROC,and WSOC | 第47-48页 |
| ·Seasonal variation of MAC and MBC | 第48-51页 |
| 5 Synthesizing and conclusions | 第51-53页 |
| References | 第53-61页 |
| 详细摘要 | 第61-64页 |