封面
声明
致谢
目录
中文摘要
英文摘要
Chapter 1 Background
1.1 Soil as a resource
1.2 Soil degradation
1.3 Soil erosion by water
1.3.1 Causes of soil-water erosion
1.3.2 Hydrological basis of water erosion process
1.3.3 Effects of water erosion
1.3.4 Variation in water erosion
1.3.5 Type of soil erosion by water
1.3.6 Soil erosion rate in China and over world
1.4 Water erosion control by pasture vegetation
1.4.1 Principles of water erosion control by vegetation
1.4.2 Action of vegetation leaves and stems on rainfall
1.4.3 The Role of ground litter cover
1.4.4 Plant roots and erosion control
1.5 On-farm fertilization to improve crop yield
1.5.1 Chemical fertilization and soil erosion
1.5.2 Sustainable agriculture fertilization
1.5.3 Soil organic matter
1.5.4 Litter decomposition (Mineralization) and Nutrients uptake
Chapter 2 Materials and Methods
2.1 Materials and experiment design
2.1.1 Study area
2.1.2 Objectives and expectations
2.1.3 Design for erosion rate assessment
2.1.4 Fertilization experimental design and treatments
2.1.5 Pastures cover experimental design
2.1.6 Soil collection and packing
2.2 Measurements methods
2.2.1 Box plot experiment measurement
2.2.2 Farm plot experiment measurement
2.2.3 Data analysis
Chapter 3 Results and Discussion
3.1 Assessment of water and soil loss from purple soil surface
3.1.1 Runoff from different treatments
3.1.2 Soil erosion responses to slope angle and rainfall intensity
3.1.3 Purple soil surface hydrological characteristics:Analyze and discussion
3.2 Runoff, Nitrogen and Phosphorus losses under rating fertilization
3.2.1 Rainfall events and Runoff volumes
3.2.2 Runoff and sediment yield relationship
4.2.3 Nitrogen and phosphorus losses
3.3 Effects of pastures grass cover on runoff and sediments reduction
3.3.1 Runoff and sediment yield
3.3.2 Runoff reduction benefit(RRB) and sediment reduction benefit (SRB)
3.3.3 Ratio between runoff and sediment reduction (RRSR)
3.3.4 Relationship vegetation cover and runoff-sediments process
Chapter 4 Conclusion and recommendations
4.1 Conclusion
4.1.1 Water and Soil loss on purple soil surface
4.1.2 Purple soil erosion responses when rating fertilization
4.1.3 Effectiveness of pastures vegetation covers to control erosion
4.2 Recommendations
参考文献