EFFECTS OF TILL VS NO-TILL ON THE QUALITY OF SOIL ORGANIC-MATTER

Changes in the quality of soil organic matter (OM) were examined in a long-term tillage experiment after 10 yr of continuous barley, to determine whether there were differences caused by tillage. The data showed that the no-till soil had a higher content of C and N (~ 26%) than the conventionallytilled soil. The whole soil and the C-enriched fraction from the no-till soil were higher in carbohydrates (~ 10 and 18% higher, respectively) and in amino acids (~ 11 and 15% higher, respectively) than the whole soil and C-enriched fractions from the conventionally-tilled soil. The no-till soil was also higher in aliphatic C (paraffins) and contained less aromatic C than the conventionally-tilled soil. The data show that the no-till systems results in quantitative and qualitative improvements in soil OM. © 1990.