Effects of Rainfall Harvesting and Mulching on Corn Yield and Water Use in the Corn Belt of Northeast China

The Corn Belt of Northeast China is the most important corn production area in China, accounting for 30% of the total corn production. However, seasonal drought conditions limit local corn production. Field experiments were conducted in 2011 and 2012 in Lishu county (Jilin Province, China) to study the effects of ridge and furrow rainfall harvesting and mulching on corn yields, evapotranspiration (ET), and water use efficiency (WUE) in black and aeolian sandy soils. The treatments included flat planting bed (FB), plastic-mulched ridges with bare furrows (RFB), and plastic-mulched ridges with straw-mulched furrows (RFM). For both soil types, the RFB and RFM treatments improved soil water conditions in the root zone. However, adding straw mulch did not consistently improve soil water content. In the black soil, the RFB treatment did not affect crop yield but increased WUE by 13% relative to the FB treatment in 2011. Furthermore, yield and WUE decreased by 30 and 24%, respectively, in 2012. In the aeolian sandy soil, the RFB treatment increased yield and WUE by 26 and 25%, respectively, relative to the FB treatment in 2011. However, the RFB treatment had no effect on yield or WUE in 2012. For both soil types, the RFM treatment did not significantly affect yield or WUE relative to the RFB treatment during 2011 or 2012. Therefore, the RFB treatment should only be used in aeolian sandy soils to achieve higher corn yields and WUEs and not be recommended for black soils when the soil water is sufficient.