Arid Zone Research ›› 2022, Vol. 39 ›› Issue (2): 493-501.doi: 10.13866/j.azr.2022.02.17

• Soil Resources • Previous Articles     Next Articles

Effects of protective measures on N2O emission from farmland soil in a semi-arid area of the Loess Plateau

DU Mengyin1(),YUAN Jianyu1,LI Guang1(),YAN Lijuan2,LIU Xingyu1,QI Xiaoping1,PANG Ye1   

  1. 1. College of Forestry, Gansu Agricultural University, Lanzhou 730070, Gansu, China
    2. College of Agriculture, Gansu Agricultural University, Lanzhou 730070, Gansu, China
  • Received:2021-10-10 Revised:2021-10-31 Online:2022-03-15 Published:2022-03-30
  • Contact: Guang LI E-mail:920446333@qq.com;lig@gsau.edu.cn

Abstract:

Nitrous oxide (N2O) is an important greenhouse gas. It has attracted much attention as a factor in climate change, and farmland soil is the main source of emissions. Among many variables affecting N2O emission from farmland, tillage is a key factor but exactly how it regulates N2O emission from dryland farmland soil is unclear. In this study, traditional tillage (T) was used as a control, and three kinds of conservation tillage were used: no tillage (NT), traditional tillage + straw mulch (TS), and no tillage + straw mulch (NTS). The soil N2O emission flux of a spring wheat field was measured by static box gas chromatography, and factors affecting N2O emission and spring wheat yield were measured concurrently. Soil N2O cumulative emissions under different tillage measures in the spring wheat field decreased in the order T > NT > TS > NTS. Emissions under treatment T were significantly higher than those under other treatments (by 15.87%, 28.08%, and 39.58%, respectively, compared with NT, TS, and NTS). In addition, compared with treatment T, conservation tillage helped to increase the surface soil content of NH4+-N and the yield of spring wheat, and reduce the accumulation of NO3--N. Correlation analysis showed that soil temperature, soil water content, and NH4+-N content were associated with soil N2O emission. Of these, soil water content and NH4+-N content showed significant negative correlations with soil N2O emission, and soil temperature showed a highly significant positive correlation with N2O emission. Based on economic and environmental benefits and considering N2O emission and crop yield, we suggest that NTS is the best tillage strategy in semi-arid areas of the Loess Plateau.

Key words: greenhouse gases, conservation tillage, farming practices, spring wheat, correlation, Loess Plateau