Effects of Irrigation Schedules on Maize Yield and Water Use Efficiency under Future Climate Scenarios in Heilongjiang Province Based on the AquaCrop Model

Abstract

Predicting the impact of future climate change on food security has important implications for sustainable food production. The 26 meteorological stations’ future climate data in the study area are assembled from four global climate models under two representative concentration pathways (RCP4.5 and RCP8.5). The future maize yield, actual crop evapotranspiration (ETa), and water use efficiency (WUE) were predicted by calibrated AquaCrop model under two deficit irrigation (the regulated deficit irrigation (RDI) at jointing stage(W1), filling stage(W2)), and full irrigation (W3) during the three periods (2021–2040, 2041–2060, and 2061–2080). The result showed that the maize yields under W1, W2, and W3 of RCP4.5 were 2.8%, 2.9%, and 2.5% lower than those in RCP8.5, respectively. In RCP8.5, the yield of W3 was 1.9% and 1.4% higher than W1 and W2, respectively. Under the RCP4.5, the ETa of W1, W2, and W3 was 481.32 mm, 484.94 mm, and 489.12 mm, respectively. Moreover, the ETa of W1 was significantly lower than W2 under the RCP4.5 and RCP8.5 (p > 0.05). In conclusion, regulated deficit irrigation at the maize jointing stage is recommended in the study area when considering WUE.

Irrigation modulates the effect of increasing temperatures under climate change on cotton production of drip irrigation under plastic film mulching in southern Xinjiang

“…The cotton yield under irrigation levels TS1–TS4 showed a decreasing trend with an increase in temperature, indicating that warming might directly affect cotton yield by impairing morphological development and plant growth ( Anwar et al., 2020 ).Cotton yield in irrigation levels TS5–TS6 increased with the temperature rise, and the difference between them was not significant, indicating that irrigation was effective for increasing yield and mitigating high-temperature stress, which could be used to directly relieve water stress on crops and indirectly reduce heat stress to reduce the dependence of crop yield on climatic conditions and even reverse the response in some cases ( Luan et al., 2021 ). Warming might directly affect crop evapotranspiration and the need for crops for irrigation water ( Nie et al., 2022 ). In our study, evapotranspiration increased with the rise in temperature because, at high temperatures, air can hold more water, increasing the potential for evapotranspiration ( Muluneh, 2020 ).…”

“…Climate changes, characterized by temperature rise, the uncertain amount and patterns of precipitation, and elevated atmospheric CO 2 concentration ( Piao et al., 2010 ), are widely concerned issues in global agricultural development ( Nie et al., 2022 ). Studies have shown that world agricultural production growth is expected to decrease at an annual rate of 1.5% by the year 2030 and then a further reduction of 0.9% by 2050, compared with 2.3% growth per year since 1961 ( Dubey and Sharma, 2018 ).…”

Responses of Soybean Water Supply and Requirement to Future Climate Conditions in Heilongjiang Province

“…The increase in RH leads to the saturation of air humidity, forming a protective layer on the field surface, thus reducing the evapotranspiration requirement [10]. However, the increase in CO 2 concentration will also promote the accumulation of crop dry matter, promote plant growth, and increase transpiration [11]. P increases soil water content, replenishes the total effective soil water, improves the plant root water absorption rate, and helps to reduce I r while meeting the needs of crop evapotranspiration [12].…”

“…Quantitative estimation of temporal and spatial variability of ET c , P e , and I r under climate change is helpful to maximize the use of rainwater resources and optimize regional water resource allocation [11,14]. P is the main influencing factor of soil moisture content, which provides water for crop evapotranspiration [26].…”

“…Therefore, there is a complex relationship between P e and I r , which cannot be fully explained by simple linear equations [28]. In addition, the relationship among ET c , P e , and I r is also affected by P distribution pattern, crop species, and planting area [11]. In the Jayakwadi command area, India, the ET c of major crops and P e increased during the growth period, resulting in less I r under climate change [29].…”