Effects of Straw Return on Soil Nitrogen Leaching

Nitrogen (N) is a major limiting factor for improvement in grain production. The return of straw to the soil (straw retum) is regarded as a very effective option to develop sustainable agriculture. Soil N content could be increased by the straw return because straw itself contains some nitrogen. However, whether N retention could be increased by the straw return is worthy of further study. In the present study, a laboratory simulative incubation experiment was conducted to study the effects of straw addition on N leaching from soil. The experimental results showed that the pH values in soil with time were changed slightly with different straw application, there was no notable change in relative abundance of microbial taxa of different straw application in soil at domain levei, and the EC of the soil did not show any clear trends after straw incorporation. The highest EC in the soil was 0.18 ds/m occurred with straw addition of 0.3%. Moreover, the N leaching amounts from soil with different straw application were decreased over time, the higher the amount of straw added in soil, the greater content of N leaching from the soil.