## 1 Introduction  
Micro-spray irrigation is a widely used irrigation method developed after sprinkling and drip irrigation [1]. With the increase of the nation's investment in civil projects and the reduction in the cost of sprinkler irrigation equipment and tapes, micro-sprinkling hose irrigation has been favored by local farmers in recent years, especially in the well-irrigated area of the North China Plain (NCP). More and more farmers are willing to accept the field water-saving technique upgrade and transformation due to soaring labor costs. Micro-sprinkling hose irrigation has the unique advantage of reducing labor and input costs. The irrigation system uses low-pressure to deliver water to micro-spray emitters through water pipes and tapes and adopts grouped multiple holes to emit water to soils, which markedly saves electricity costs in irrigation. The technique breaks the limitation that a large irrigation quota is essential for traditional flood irrigation to guarantee good irrigation uniformity, whereas micro-sprinkling hose irrigation can achieve a higher uniformity at the expense of a small irrigation quota [2]. Moreover, the low-pressure technique of the irrigation system saves water resources and labor costs. The irrigation system is also conducive to the integration of water and fertilizer [3]. At present, micro-sprinkling hose irrigation for cereal crops mostly refers to the conventional spray irrigation system. It had the traits of \"frequent irrigation with small quota.\" On the contrary, traditional flood irrigation had the characteristic of \"less irrigation with a large amount.\" Nevertheless, in some areas, improper irrigation regimes and schedules of the micro-sprinkling hose irrigation system often occur, regardless of the implementation of the advanced irrigation system. That is, some of the farmers still adopted traditional irrigation regimes and schedules with \"larger water amount and lower irrigation times\" for the micro-spray system, resulting in a reduction in grain yield and farmers' benefits [4]. Of course, there are still some problems to be solved in the use of micro-sprinkling hose irrigation. For example, the irrigation quality was greatly affected by wind during irrigation, and the thin and soft micro-sprinkling hose was very easy to twist and fold after irrigation. Therefore, windless or breezy weather was often selected for irrigation, and the sprinkler belt didn't roll up until the end of the growth period after irrigation. In a word, how to develop a scientific and reasonable micro-sprinkling hose irrigation system based on local conditions to achieve the dual goals of water saving and yield increasing has attracted more and more scholars' attention. Applying the micro-spraying system to irrigate winter wheat crops during the growth period can better solve the problems existing in traditional flooding irrigation and is conducive to increasing grain yield and WUE [5; 6; 7; 8; 9]. When the planned irrigation quota is determined, the tape length and working pressure can be reasonably selected according to the hydraulic performance of a micro-spraying system, such as the longitudinal slope of the field, micro terrain, soil permeability, and other factors as well [10; 11; 12; 13]. The spraying width of micro-spraying tapes is closely related to the tape length and working pressure, which largely determines the field layout spacing of the micro-spraying tapes. Under the condition that the tape length and working pressure are already known, a larger field spacing is more beneficial to give a full display of the advantages of rapid supplementary irrigation of the micro-spray system. However, its irrigation quality and uniformity are often difficult to be effectively guaranteed. In addition, the plant barriers during the middle to late stages of wheat crops significantly reduced the spraying width and seriously affected the irrigation uniformity of the micro-spraying system [14; 15].