Adaptability of shallow subsurface drip irrigation of alfalfa in an arid desert area of Northern Xinjiang.

A suitable irrigation method adopted to arid desert conditions, including a special soil structure and specialized plants, has been continuously studied and improved. A field study was conducted in the Awei irrigation area of Aletai in Xinjiang in 2015 and 2016 to investigate the applicability of shallow subsurface drip irrigation (SSDI) in an arid desert area. A completely randomized block design with three replications and three treatments for drip tape subsurface depths at 5, 10, 20 cm was established. The results indicated that the vertical distribution of the soil moisture of subsurface drip irrigation (SDI, buried depth at 20 cm) was mainly concentrated at 0-60 cm, while SSDI (buried depth at 5 and 10 cm) was concentrated at 0-30 cm. However, the roots distributions were concentrated at 0-30 cm for SDI and SSDI. The chlorophyll content and water consumption intensity for alfalfa first increased and then decreased in arid desert conditions. The dry yield and water use efficiency (WUE) of SSDI (buried depth at 10 cm) were higher than those of SDI. The SSDI was practical in arid desert conditions and the recommended buried depth was 10 cm.