Effects of Different Ways to Return Biomass on Soil and Crop Nutrient Contents

摘要

Using wheat and corn as the selected crops, this study aims to explore the effects of different ways to returnbiomass, on soil and crop yield with wheat and corn straw, and the biochar made by them as the material.The results exhibited that the different ways of returning biomass could significantly improve the soil cationexchange capacity (CEC) and the content of organic matter after the harvesting of two annual crops. Thesoil nutrient content showed a rising trend in general, and the effect was most significant when the biocharconsumption was the most. The soil total nitrogen content in wheat and corn season significantly increasedby 100% and 16.2% respectively compared with the control. The soil mineral nitrogen content and availableP content in wheat season significantly increased by 0.9% and 217% respectively compared with the control.And the soil mineral nitrogen content, available P content and available K content in corn season significantlyincreased by 21.2%, 30% and 90% respectively compared with the control. The effects of direct strawapplication to soil was a bit poor, and it had no significant effect on crops yield, but it can promote plants toabsorb nutrients, and the effect increased with the increase of biomass usage. The effect of sole biocharapplication is better than that of direct straw application..