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A mechanical and ecological tillage pattern (MET) which combined ploughing, rotary tillage of seeding strip, no-tillage and subsoiling in four years for a cycle was designed. To study the short-term effects of the pattern on physical and chemical characteristics of soil and groups yields in arid area, the positing experiment of four years in wheatcorn two cropping area was carried on and with continuous no-tillage (CNT) and conventional tillage (CCT) for comparison. The experiment results showed that the MET improved the quality of soil structure and soil fertility significantly, prevented soil harden, and the ecological and fertile soil effects were remarkable. It increased the aggregate content in 0 ~ 30cm soil layer significantly and improved soil structure stability, and the average aggregate content of water stability was 8.2% and 30.4% higher than those of the CNT and CCT, respectively. It reduced the bulk density of soil in 0 ~ 30cm soil layer effectively, its average bulk density was 0.089g/cm3 and 0.125g/cm3 smaller than those of the CNT and CCT. It increased the content of total nitrogen, rapid available phosphorus and rapid available potassium in 0 ~ 30cm soil layer as well, but there were no significant impacts on the content of available nitrogen. It added the content of organic carbon, the organic carbon content in MET was 0.36g/kg and 0.61g/kg higher than those in CNT and CCT, respectively, and the organic carbon concentration distribution was balanced between the layers of 0~10cm,10~20cm and 20~30cm.However, the CNT only added the organic carbon content in 0~10cm soil layer and the CCT only increased the organic carbon content in 10~20cm soil layer. The MET increased wheat yields significantly by increasing the average wheat tillering, effective spike and grain number per spike, the wheat yields of MET was 14% and 14.9% higher than those of CNT and CCT, respectively. The tillage methods before wheat sowing had after effects to a certain extent on corn, the MET and the CNT improved the corn yields by increasing the effective ear of corn and grain number per spike, the corn yields of the MET and CNT were 7.4% and 3.7% higher than that of CCT, respectively, but there was no significant difference between them.