Field experiments were employed to investigate effects of whole field mulching with soil covering and bunch planting (WFMS) on wheat grain yield, with a randomized block design with four treatments: (i) whole field mulching with soil covering and bunch planting (WFMS), (ii) whole field mulching without soil covering and bunch planting (WFM), (iii)film-mulched ridge-furrow(FMRF), (iv) un-mulched with row-seeding (CK). The results showed that degree of yield increase in WFMS was significantly higher than that in WFM. Compared with CK, the average yieldof the three patterns was increased by 73.9%, 60.3% and 33.3%, with the yield increased by 2 457.9, 2 007.2 kg·hm-2 and 1 045.9 kg·hm-2, respectively. And the order for WFMS was dry semi-arid area>semi-arid area> dry semi-humid area . Compared with CK, yield increased by WFMS was 90.2%, 73.7%, and 57.8% for the three areas, respectively, with an order of dry semi-humid area>semi-arid area>dry semi-arid area. Compared with CK, the yield increase of WFMS in three arid areas were 2 220.3, 2 520.9 kg·hm-2 and 2 632.5 kg·hm-2, respectively. Especially in the arid area with annual precipitation between 500 mm and 600 mm, the average yield of WFMS was 7 183.5 kg·hm-2 and the highest yield was 7 405.5 kg·hm-2, being the highest for dryand wheat in these areas. |