Evaluation of no-tillage impacts on soil respiration by 13C-isotopic signature in North China Plain

It is a challenge to characterize soil respiration of crop residue return systems in the North China Plain (NCP) under notillage (NT) and conventional tillage (CT) practices. In this study, we addressed the hot spot research challenge of impacts of tillage practices on soil carbon storage and soil CO2 emissions in the NCP by C-13-isotopic signature. A short-term (2018-2020) field experiment was conducted with two tillage practices: NT and CT. The results showed that in the tested area, NT had advantages of lower CO2 emissions compared to CT with average reduced CO2 emissions by 10.82%-19.14%. The results of this study suggested that the NT facilitated enhanced soil carbon storage by 2.80%, which was evidenced by the delta C-13 data. Based on the path analysis model, the main line of soil respiration reduced by NT was attributed to the increased of soil microbial carbon and nitrogen as well as soil moisture in NT, which further increased delta C-13 and eventually inhibited soil respiration. Overall, adopting NT in NCP is an effective means to improve soil carbon pool and decrease soil CO2 emissions in agriculture practices.

Automated summary

This study investigated the impacts of different tillage practices on soil carbon storage and CO2 emissions in the North China Plain using C-13 isotopic signature. The results showed that no-tillage (NT) had lower CO2 emissions compared to conventional tillage (CT), and NT facilitated enhanced soil carbon storage. This was attributed to the increased soil microbial carbon and nitrogen as well as soil moisture in NT, which inhibited soil respiration.