Assessment of the impact of future climate change on maize yield and water use efficiency in agro‐pastoral ecotone of Northwestern China

Abstract

Maize plays an important role in the Agro‐pastoral ecotone of Northwestern China (APENC), where highly sensitive to changes in climate conditions. However, little is reported on the impacts of climate change on crops in the region. In this study, we used Decision Support System for Agrotechnology Transfer model driven by future climate data from 20 general circulations models under two representative concentration pathways (RCPs: RCP4.5 and RCP8.5) from the Coupled Model Intercomparison Project Phase 5 (CMIP5) to project the effects of climate change on maize yield and water use efficiency (WUE) in eight future time periods (interval: 10 years; from 2020s to 2100s). The model was first calibrated based on field observation for phenology, leaf area index, maize yield and calibrated and evaluated results were reasonably good. Simulated results showed that without and with consideration of CO2 effects, maize yield at the end of the 21st century will decrease by 11.7% and 10.3% under the RCP4.5 scenario, and by 22.1% and 21.2% under the RCP8.5 scenario, respectively. We found that there is a significant correlation between maize yield reduction and warming. Specifically, when the increment of annual average temperature reaches 1°C, the maize yield begins to decrease by 11.27% and 10.8% per 1°C warming without and with consideration of CO2 effects, respectively. Furthermore, high temperature not only affects maize yield but also has a negative effect on WUE. The WUE would change by −8.1% and −18.8% under RCP4.5 and RCP8.5, respectively. But if we consider the effects of CO2, the WUE will improve 1.5% under RCP4.5 and 2.2% under RCP8.5, in comparison to those without consideration of CO2 effects. Overall, future climate warming will seriously affect maize yield and WUE. Although the increase of CO2 concentration is beneficial to raise maize yield and WUE, it is hard to offset the negative effects of the increase in temperature. Besides, change in the planting date can be beneficial for the adaptation of maize to climate change in the APENC. These results will provide comprehensive information to support local policy and decision‐making in agricultural production and water resources management.

Interactive effect of elevated [CO2] and temperature on the photosynthetic process, anti‐oxidative properties, and grain yield of rice

“…There was an increase of 81–82% higher WUE in IR64 and 73–85% increase in IR 83376‐B‐B‐24–2 during wet season 2014 and 2015, respectively. Han et al (2021) also reported that high temperature has negative effect on WUE of maize. Higher [CO 2 ] levels will influence stomatal behaviour beneficially by reducing water loss through transpiration, thus increasing water use efficiency (Wassmann et al, 2009).…”

Modelling the climate change impact of mitigation (RCP 2.6) and high emission (RCP 8.5) scenarios on maize yield and possible adaptation measures in different agroclimatic zones of Punjab, India

“…A study in north-western China for the end of the 21st century predicted a decline under the four climate scenarios and more significantly under RCP 8.5. 37 The rising temperatures within 1 °C would not cause a significant effect but higher than that would lead to losses in maize yield by 11.3% with fertilization effects of CO 2 concentration and by 10.8% without the fertilization effect of CO 2 concentration. The elevated CO 2 has a positive impact on maize yield but the increasing temperatures offsets this positive impact.…”

Assessing the Effects of Spatial Scales on Regional Evapotranspiration Estimation by the SEBAL Model and Multiple Satellite Datasets: A Case Study in the Agro-Pastoral Ecotone, Northwestern China

“…The Yuyang District is located at 37.81 • -38.92 • N, 108.94 • -110.41 • E (Figure 1), Shaanxi Province, China, and covers a total area of~7000 km 2 . This area is part of the ecologically fragile transition zone between the desert-grassland area and the Loess Plateau region [13,[49][50][51][52]. The region has a semi-arid continental monsoon climate, with an average annual temperature of 8.4 • C and an average annual precipitation of 402 mm that gradually decreases from the southeast to northwest.…”