Biochar application influences the stability of soil aggregates and wheat yields

Abstract

In the present study, a field establishment was initiated in 2018 with eight treatment conditions using biochar application rates of 0, 10, 20, or 30 t/ha and nitrogen application rates of 0 or 150 kg/ha. After two years, the impact of biochar on carbon-nitrogen distributions, soil aggregate stability, and wheat yields was then assessed. The predominant mechanical aggregates after two years were > 5 mm and 2-5 mm granular aggregates, with notable increases in the amounts of these aggregates following the application of biochar with or without nitrogen that coincided with an increase in soil aggregate mechanical stability. Relative to control conditions, aggregate mean weight diameter (MWD) and geometric weight diameter (GMD) values rose by 17.6% and 24.3% for biochar with nitrogen treatment (N: 150 kg/ha; biochar: 20 t/ha), respectively. Biochar application alone and the application of both biochar and nitrogen fertiliser were associated with 6.4-20.2% and 20.7-42.7% increases in spring wheat yields, respectively. Overall, the results of these analyses highlight the value of applying biochar to improve soil quality and boost crop yields proximal to the study site. This study provided the scientific basis for the rational fertilisation and scientific management of biochar combined with nitrogen fertiliser in the irrigation area of Northern Xinjiang, China.

Keywords

• soil structure
• c/n ratio
• sustainable agriculture
• carbon fixation