Application of subsoiling technology in long term no-till field of North China

摘要

Mechanical subsoiling technique is a major measure for conservative cultivation in dry land.Subsoiling machinery is an effective way to realize subsoiling operation.Conservation tillage coupled with subsoiling in northern China is widely believed to reduce soil compaction,which was created after many years of no-till.The conservation tillage demonstration sites operating for 10 years in northern China were used to conduct a comparative study of subsoiling technology under conservation tillage.Three modes of traditional tillage (TT),subsoiling with soil cover (SSWC) and no-till with soil cover (NTWC) were compared using ten years of soil bulk density,water content,yield and water use efficiency data.After eight years,the study shows in the maize experimental plots at Shouyang,the average soil bulk density for each tillage mode of TT,SSWC and NTWC were 1.23Mg/m3,1.28Mg/rn3,1.35Mg/m3 which was significantly high while comparing with TT whereas in wheat crops TT and NTWC showed the lowest and highest soil bulk density,respectively.SSWC and NTWC reduced soil moisture loss compared to TT during the nine years from 1992to 2000.The trend on maize and wheat yield over the 8 years indicated that SSWC and NTWC were 10 to 12％ higher compared to TT.NTWC had higher water use efficiency (WUE) than TT each year by 3％ to 26％ whereas in comparison with TT,SSWC was 5％ to 31％ higher throughout the years.The findings from the long term study on subsoiling incorporating with no-tillage laid a solid foundation for subsoiling technology extension and application in China.