Spring Wheat Performance and Water Use Efficiency on Permanent Raised-beds in Arid Northwest China

摘要

In arid northwest China, currently almost all irrigated crops are conventionally planted in narrow spaced rows on fiat and is irrigated by flood irrigation, which resulted in low crops yields and inefficient use of irrigation water. Permanent raised-beds (PRB) are being proposed for irrigated crops in arid northwest China to increase soil productivity and to save water. However, limited research has been conducted on the synthetical effects of PRB practice in irrigated areas in China. From 2005 to 2007, we conducted a field experiment on spring wheat to investigate the effects of permanent bed planting with furrow irrigation on crop growth, yield and water use efficiency (WUE). The field experiment was conducted using traditional tillage (TT), zero tillage (ZT) and permanent raised-beds (PRB) in Hexi Corridor at Zhangye, northwest China. PRB significantly increased soil water content of spring wheat growing period by 3-8%to 100 cm depth and soil temperature by 0.2-0.9<'0>C to 5cm depth relative to TT and ZT treatments. Bulk density to 10cm depth was about 5.8% lower for permanent bed planting than for flat planting treatments. The spring wheat yield and WUE were also affected by the planting and irrigation mode. The mean spring wheat yields over 3 years on PRB plots were about 2% higher than in TT and ZT plots due to higher soil moisture and temperature, lower bulk density and faster growth. Permanent bed planting with furrow irrigation was particularly effective in increasing the use efficiency of irrigation water. Compared with TT and ZT treatments, PRB treatment significantly enhanced 18% of WUE. The improvements in crop yield and WUE have tremendous implications in the arid areas of northwest China where agriculture relies heavily on irrigation, but water resources are scarce. We conclude therefore that PRB farming system is an efficient way to promote crop growth, and significantly improve yield and WUE in arid areas of northwest China.