Effects Of Simplified Crop Establishment And Rice Straw Incorporation On Soil Properties And Rice Yield

Simplified cropping is a new cultivation technology which can reduce production costs, save labor resources, increase crop yield. The simplified cropping of rice were including mechanical tillage instead of human and animal, throwing slingling and direct seeding instead of transplant rice seedlings. Mechanical tillage provides a convenient on the straw returned. Throwing slingling and direct seeding have changed the dynamic features of root and nutrient distribution which may make a long-term effect on soil nutrient and structure. Through5years of observation of the long-term experimental site at YuJing country in JiangXi province and combined with the indoor simulation test, the goals of this study were:1) Clear tillage depth, straw incorporation and planting patterns influenced the dynamic of rice yield and content of soil organic carbon, soil available N, P, K.2) Understand tillage depth, straw incorporation and planting patterns played a part in the distribution of nutrient and root.3) Definite the tillage depth and straw incorporation affected the mechanism of soil structural properties.The results can provide technical and theoretical support to improve rice yield and quality.The main results were as follows:1. The straw incorporation can significantly increase the rice yield than straw removal.The range of rice yiled under deep tillage method was bigger than shallow ones, while the extent of available nutrient under shallow tillage method was bigger than deep ones.The yield of straw incorporation treatment was significantly higher the yield of removal ones by3.9%.The yield in deep tillage treatments was bigger than the one in shallow tillage. Compared with deep tillage, the shallow one can significantly increase soil organic carbon (SOC), alkali-hydrolysable N and available P in the dynamic process by5.2%,5.4%and15.9%, respectively.2. There was an obvious stratification about soil nutrient and root in the soil profile. Shallow tillage can be in favour of nutrient gather on surface layer (0-5cm).While in deep tillage method, the available nutrient and root in deep soil layer were higher than shallow tillage in the same layer. Highly significant correlation were found between root index including weight, length, surface area, volume, average diameter, tips and soil nutrient including soil organic carbon, alkali-hydrolysable N, available P in each layer except K.3. Soil organic carbon input was one of the most important factors on the soil mechanical property. The higher content of organic carbon input, the smaller sinkage capacity and penetration resistance were existed. The higher content of organic carbon input can cause a bigger value of tensile strength. The treatments with higher organic input owned the higher COLE and more macro pore.Conclusively, combination simplified cropping technology and straw incorporation can increase soil nutrient content, promote rice yield and improve the mechanical property.There was usless to create more deep layer in the wet-dry cycles.