Response of dryland crops to climate change and drought-resistant and water-suitable planting technology: A case of spring maize

Abstract

Climate change has a significant impact on agriculture. However, the impact investigation is currently limited to the analysis of meteorological data, and there is a dearth of long-term monitoring of crop phenology and soil moisture associated with climate change. In this study, temperature and precipitation (1957–2020) were recorded, crop growth (1981–2019) data were collected, and field experiments were conducted at central and eastern Gansu and southern Ningxia, China. The mean temperature increased by 0.36°C, and precipitation decreased by 11.17 mm per decade. The average evapotranspiration (ET) of winter wheat in 39 years from 1981 to 2019 was 362.1 mm, demonstrating a 22.1-mm decrease every 10 years. However, the ET of spring maize was 405.5 mm over 35 years (1985–2019), which did not show a downward trend. Every 10 years, growth periods were shortened by 5.19 and 6.47 d, sowing dates were delayed by 3.56 and 1.68 d, and maturity dates advanced by 1.76 and 5.51 d, respectively, for wheat and maize. A film fully-mulched ridge–furrow (FMRF) system with a rain-harvesting efficiency of 65.7-92.7% promotes deep rainwater infiltration into the soil. This leads to double the soil moisture in-furrow, increasing the water satisfaction rate by 110-160%. A 15-year grain yield of maize increased by 19.87% with the FMRF compared with that of half-mulched flat planting. Grain yield and water use efficiency of maize increased by 20.6 and 17.4% when the density grew from 4.5×104 to 6.75×104 plants ha–1 and improved by 12.0 and 12.7% when the density increased from 6.75×104 to 9.0×104 plants ha–1, respectively. Moreover, responses of maize yield to density and the corresponding density of the maximum yield varied highly in different rainfall areas. The density parameter suitable for water planting was 174 maize plants ha–1 with 10 mm rainfall. Therefore, management strategies should focus on adjusting crop planting structure, FMRF water harvesting system, and water-suitable planting to mitigate the adverse effects of climate change and enhance sustainable production of maize in the drylands.