In order to investigate the effect of plastic film mulching on the movement of soil nutrients and yield of rainfed potato in semiarid areas of Gansu Dingxi, Six treatments were conducted, including harrowed bedding system without plastic mulching (T1), harrowed bedding system with plastic mulching (T2), completely mulched alternating narrow and wide ridges with furrow planting (T3), completely mulched alternating narrow and wide ridges with ridge planting (T4), plastic mulched raised bedding system with furrow planting (T5) and plastic mulched raised bedding system with bedding planting (T6). The results indicated that plastic film and ridge-furrow practices can increase the content of soil available nitrogen, phosphorus, potassium and soil organic matter. In 0～20 cm soil layer, soil available nitrogen, phosphorus, and potassium showed similar trend, increasing in the first stage, and then decreasing. The nutrient contents were highest in July, the content of soil organic matter of film and ridge-furrow treatments in 0～40 cm soil layer were higher than that in T1. Moreover there were higher nutrient contents in film and ridge-furrow treatments than T1. In 20～40 cm soil layer, the content of soil available nitrogen, phosphorus and potassium was also changed the same, decreased in the first stage, then increased, and decreased finally, and the nutrient contents were highest in August. Compared with T1, the yield of T2, T3, T4, T5, and T6 was increased by 36.3%, 59.7%, 60.5%, 47.6%, and 46.0%, respectively. Plastic film and ridge-furrow cropping patterns increased the yield of potato, especially the ratio of large and medium tubers, with the treatment of completely mulched alternating narrow and wide ridges with ridge planting (T4) showing the highest values.

In order to investigate the effect of plastic film mulching on the movement of soil nutrients and yield of rainfed potato in semiarid areas of Gansu Dingxi, Six treatments were conducted, including harrowed bedding system without plastic mulching (T1), harrowed bedding system with plastic mulching (T2), completely mulched alternating narrow and wide ridges with furrow planting (T3), completely mulched alternating narrow and wide ridges with ridge planting (T4), plastic mulched raised bedding system with furrow planting (T5) and plastic mulched raised bedding system with bedding planting (T6). The results indicated that plastic film and ridge-furrow practices can increase the content of soil available nitrogen, phosphorus, potassium and soil organic matter. In 0～20 cm soil layer, soil available nitrogen, phosphorus, and potassium showed similar trend, increasing in the first stage, and then decreasing. The nutrient contents were highest in July, the content of soil organic matter of film and ridge-furrow treatments in 0～40 cm soil layer were higher than that in T1. Moreover there were higher nutrient contents in film and ridge-furrow treatments than T1. In 20～40 cm soil layer, the content of soil available nitrogen, phosphorus and potassium was also changed the same, decreased in the first stage, then increased, and decreased finally, and the nutrient contents were highest in August. Compared with T1, the yield of T2, T3, T4, T5, and T6 was increased by 36.3%, 59.7%, 60.5%, 47.6%, and 46.0%, respectively. Plastic film and ridge-furrow cropping patterns increased the yield of potato, especially the ratio of large and medium tubers, with the treatment of completely mulched alternating narrow and wide ridges with ridge planting (T4) showing the highest values.