Effect of rainfall concentration with different ridge widths on winter wheat production under semiarid climate

Ridge and furrow rainfall concentration (RC) system has gradually been popularized to increase water availability to crops for improving and stabilizing agricultural production in the semiarid area of northwest China. The system is comprised of two elements: the plastic-covered ridge serves as rainfall harvesting zones and the furrow serves as planting zones. To make this system more perfect for alleviating drought stress in semiarid region, it is necessary to test optimum planting systems. A field experiment was conducted from 2007 to 2010 to evaluate the effects of RC planting on soil moisture, wheat yield and water use efficiency (WUE) under different ridge widths. Four planting systems were designed (RC40: 40 cm ridge with 60 cm furrow width, RC60: 60 cm ridge with 60 cm furrow width, RC80: 80 cm ridge with 60 cm furrow width, and CF: conventional flat without ridging). The results showed that RC planting can significantly increase soil moisture in 0-200 cm during the growing seasons of winter wheat. The rainfall-harvesting effect increased with ridge width increasing. Winter wheat yield and WUE was significantly higher under RC60 than under CF by 405.1 kg ha(-1) and 2.39 kg mm(-1) ha(-1), respectively, on average across the three experimental years (P < 0.05). The above findings indicate that RC60 can benefit winter wheat cropping for higher yield through improving soil moisture. It could be concluded that the RC planting system with 60 cm ridge and furrow width will offer a sound opportunity for sustainable farming in semiarid dryland agricultural area. (C) 2016 Elsevier B.V. All rights reserved.