Appropriate ridge-furrow ratio can enhance crop production and resource use efficiency by improving soil moisture and thermal condition in a semi-arid region

Abstract

The plastic-mulched ridge and furrow rainwater harvesting (PRFRH) system improves precipitation utilization and yield in semi-arid regions. For densely planted crops such as winter wheat, however, the ridges reduce planting area. Thus, optimal ridge and furrow configurations for winter wheat cultivation remain unknown. Here, we evaluated the effects of various ridge-furrow ratios on soil hydrothermal properties, winter wheat growth, yield, resource use efficiency, and profitability under different precipitation years (dry, normal, or wet years) in 2014–2017. A control (CK, conventional flat planting without mulching) and three different ridge-furrow ratios [40:60 (R40), 60:60 (R60), and 80:60 (R80)] were tested. Firstly, PRFRH increased soil water storage and temperature. The soil moisture content assumed a “bell-shaped” distribution which was centered on the planting furrow in the 0−80 cm range. The soil water storage increased with mulched-ridge width, but it will not significantly increase while the mulched-ridge width was too wide. The soil temperature of ridge also increased with mulched-ridge width, whereas the soil temperature decreased in furrow. Moreover, precipitation years had no obvious effect on soil water storage or temperature. Secondly, the dry matter accumulation was captured quite well by the Logistic (R2 > 0.99). PPRFRH promoted the accumulation of dry matter and increased the winter wheat yield (17.7%), especially in dry year, which mitigated the impact of drought and maintained the yield. Similarly, dry matter accumulation and yield also increased with mulched-ridge width. In contrast, when the ridge was too wide, the effective duration of dry matter accumulation and the yield were reduced. Finally, PRFRH improved the utilization efficiency of water, precipitation and thermal. Nevertheless, the mulched-ridge width required for optimal water-related resource utilization was higher than that needed for optimal thermal utilization. Overall, our results suggest that a 60:60 cm ridge and furrow system can improve dry matter accumulation, crop yield, profitability, and hydrothermal use efficiency in winter wheat grown in the semi-arid regions.