以黑龙江省松嫩平原为研究区，探究不同降水年型下灌溉对玉米产量和水分利用的影响，并制定科学合理的玉米灌溉方案，以提高农业水资源的利用效率。考虑玉米不同生育期和灌水定额的影响，共拟定37种灌溉方案，并将其输入本地化的水作物模型（AquaCrop）中进行模拟分析。研究将探究不同降水年型下雨养和灌溉对玉米产量、水分利用效率（Water use efficiency，EWU）和灌溉水利用效率（Irrigation water use efficiency，EIWU）的影响，确定关键灌溉期。通过对不同降水年型下玉米产量和EWU的对比关系进行分析，确定最优的灌溉制度。结果表明：AquaCrop模型能较好地模拟松嫩平原玉米的生长过程；在玉米关键生育期，适时适量的灌溉能确保作物获得足够的水分，减少产量损失，提高EWU，但过度灌溉会导致两者降低；综合考虑玉米产量和EWU，在特枯水年，苗期-拔节期（20 mm）、拔节-抽雄期（60 mm）和抽雄-灌浆期（60 mm）为最优灌溉方案，在枯水年，拔节-抽雄期（60 mm）和抽雄-灌浆期（60 mm）为最优灌溉方案，平水年和丰水年降水可以满足玉米水分需求，不需要灌溉。研究可为黑龙江省松嫩平原地区制定更加合理和有效的玉米灌溉制度提供一定的理论依据，从而更好地应对气候变化和水资源短缺带来的挑战，保障粮食安全。

The sustainable utilization of water resources and the guarantee of food security are the basic support points for the sustainable development of society, while crop production is a prerequisite for guaranteeing food security. Heilongjiang Province is an important commercial grain production base in China, and has an important strategic position in guaranteeing national food security. Heilongjiang Province is located in one of the world's three major black soil belts, which is recognized as the world's golden growth zone for maize. According to statistics, in 2021, the sown area of maize in Heilongjiang Province was about 652.4×104 hm2, accounting for 44.8% of the total sown area of grain in the province, and its output accounted for 37.7 % of the national total maize production. The main planting areas of maize in Heilongjiang Province are concentrated in the three regions of Qiqihar, Suihua and Harbin, which are all in the Songnen Plain region of Heilongjiang Province. However, the region has undergone significant environmental changes due to the trend of aridification, and water scarcity is a serious problem that limits maize growth and development processes. In addition, numerous studies have shown that drought often occurs during the reproductive period of maize, and that in dry years, maize production can be increased through scientifically sound irrigation measures, while in years of high water availability, when precipitation can basically satisfy maize water demand, care needs to be taken to avoid over-irrigation that leads to wasted water resources and crop damage. In this study, based on 60 years of long-term historical meteorological data, the modified AquaCrop model was used to simulate maize yields under different rain-fed and irrigated scenarios for different precipitation year types at each typical site in the Songnen Plain, and water use efficiency and irrigation water use efficiency were further computed in order to assess the efficiency of water resource use under different precipitation year types. Finally, the data were spatially interpolated using ArcGIS, and the results were visualized as maps for a better understanding of maize yield and water use in different regions. The results show that: In extremely dry and dry years, the irrigation combination of seedling stage - jointing (20 mm), jointing stage - pulling stage (60 mm) and pulling stage - filling stage (60 mm) was the best irrigation scheme. The yield of maize was 11.33 and 10.23 t/hm2, and the average WUE was 2.35 and 2.16 kg/m3, respectively. Irrigation can alleviate the effects of drought on yield. The optimal irrigation scheme in normal water year was the soxion-filling period (60 mm), but the irrigation yield only increased by 0.1 t/hm2,and the average WUE only increased by 0.028 kg/m3. If the seedlings could emerge neatly, irrigation would not be allowed in normal water year. In wet years, precipitation can meet the water demand of maize without irrigation. For normal and wet years, rain-fed agriculture can obtain similar yield and WUE. Therefore, irrigation strategies should be differentiated according to hydrological years. Irrigation should not be done in wet years to save water resources, and adequate water should be required in dry years, especially in the key growth stages of maize during jointing - pumping and pumping - filling. In addition, planting dates need to be adjusted to climate change trends to make the most of natural precipitation and reduce irrigation needs. Future studies should comprehensively consider the effects of climate change, soil moisture and maize variety improvement, so as to provide a theoretical basis for formulating a reasonable and effective maize irrigation system, cope with the challenges of climate change and water shortage, and ensure food security. Conclusion:(1) AquaCrop model can effectively simulate the growth process of maize in the Songnen Plain. During the critical growth stages of maize, timely and appropriate irrigation can ensure that the crop receives sufficient water, reduce yield loss, and improve Water Use Efficiency (WUE). However, over-irrigation can lead to a decrease in both. As yields increase, WUE may decline because higher yields may require more water. In extremely dry years, the optimal irrigation schemes are 20 mm from the seedling to jointing stage, 60 mm from the jointing to tasseling stage, and 60mm from the tasseling to filling stage. In dry years, the optimal schemes are 60 mm during the jointing to tasseling stage and 60 mm during the tasseling to filling stage. In normal and wet years, precipitation is sufficient to meet the maize’s water needs, and no irrigation is required. This study can provide a theoretical basis for developing a more rational and effective maize irrigation system in the Songnen Plain of Heilongjiang Province, thereby better addressing the challenges of climate change and water scarcity, and ensuring food security.

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黑龙江大学杰出青年科学基金（JCL202105）；国家自然科学基金（52109055）