Integrative impacts of soil tillage on crop yield, N use efficiency and greenhouse gas emission in wheat-corn cropping system

Wheat-corn cropping system is one of the most important grain production systems in theworld. However, the integrative impacts of soil tillage on crop yield, N use efficiency (NUE)and greenhouse gases (GHGS) emissions are not well documented in this system. Thus, a twoyear field experiment was carried out in a typical wheat-corn cropping system with four tillageregimes during the wheat season, including no-tillage (NT), rotary tillage (RT), sub-soilingtillage (ST) and sub-soiling with rotary tillage (SRT) in a randomized block design with threereplicates. No-tillage was conducted for all treatments during corn season. Over the two years,the highest yields of wheat, corn and annual were found in the SRT treatment, while the lowestannual yield was found in the NT treatment averagely. Two-year average annual yield in theSRT was 19643.9 kg ha-1, which was 4.8, 5.9 and 7.7% higher than that in the ST, RT and NTtreatments, respectively (P<0.05). SRT also stimulated plant N uptake with a higher N harvestindex and higher partial factor productivity (PFP) than those under the other tillage practices(P<0.05). Although SRT stimulated N2O emission in wheat season, it significantly reduced theemission in corn season compared with the NT (P<0.05). Thus, no significant differences intotal GHGS emissions, area-scaled and yield-scaled global warming potential (GWP) werefound among the tillage practices. Our results indicate that sub-soiling with rotary tillage mightbenefit crop production for high yield and N use efficiency with less GHGS emissions forwheat-corn cropping system in North China Plain.

کلیدواژه ها:

Soil management ، Available N ، Grain production ، N2O ، CH4 ، Global warming potential