Sun Bokai, Wang Weiguang, Liu Guoshuai, Li Hongbin
The National Key Laboratory of Water Disaster Prevention, Hohai University, Nanjing 210098, China; College of Hydrology and Water Resources, Hohai University, Nanjing 210098, China.
The National Key Laboratory of Water Disaster Prevention, Hohai University, Nanjing 210098, China; College of Hydrology and Water Resources, Hohai University, Nanjing 210098, China.
Sci Total Environ. 2024 Feb 20;912:168489. doi: 10.1016/j.scitotenv.2023.168489. Epub 2023 Nov 22.
Climate change and elevated CO concentrations significantly affect rice growth and water consumption. Understanding the specific impacts of climate change and elevated CO concentrations on rice physiological phenology, crop water demand (ET), and irrigation water requirement (IR) is of great significance for the sustainable utilization of water resources and food security. This is particularly true in China, the world's largest rice producer. In this study, with the help of two rice phenological models, the modified Penman-Monteith equation, and the paddy water balance model, we project the changes in rice phenological period, ET, and IR in four main rice-producing regions of China in the period 2015-2100 based on the 11 GCM outputs. The results show that the rice growing period is shortened in most rice-producing regions, except for the parts of the middle and lower reaches of the Yangtze River. Meanwhile, the trend of ET and IR of rice varies slightly among regions in the future scenario, with almost all regions decreasing yearly except for the middle and lower reaches of the Yangtze River, where the trend is increasing. The progressively increasing atmospheric CO concentration has a "fertilization effect" on the crop, which can reduce the water requirements of rice. In the SSP585 scenario, the " CO fertilization effect" can reduce up to 8.87 × 10 m of ET and 6.94 × 10 m of IR in the middle and lower reaches of the Yangtze River in the period of 2090s. This study provides beneficial references to understand the response of rice ET and IR to future climate change and CO concentration elevation in China and highlights that the simulation in terms of crop irrigation must account for the "CO fertilization effect".
气候变化和二氧化碳浓度升高显著影响水稻生长和水分消耗。了解气候变化和二氧化碳浓度升高对水稻生理物候、作物需水量（ET）和灌溉需水量（IR）的具体影响，对于水资源的可持续利用和粮食安全具有重要意义。在中国这个世界最大的水稻生产国尤其如此。在本研究中，借助两个水稻物候模型、修正的彭曼-蒙特斯方程和稻田水平衡模型，我们基于11个全球气候模型（GCM）的输出结果，预测了2015-2100年中国四个主要水稻产区水稻物候期、ET和IR的变化。结果表明，除长江中下游部分地区外，大多数水稻产区的水稻生长周期缩短。同时，在未来情景下，水稻ET和IR的变化趋势在不同地区略有不同，除长江中下游地区呈上升趋势外，几乎所有地区的ET和IR都逐年下降。大气中二氧化碳浓度的逐渐升高对作物具有“施肥效应”，可以降低水稻的需水量。在SSP585情景下，“二氧化碳施肥效应”在2090年代可使长江中下游地区的ET减少多达8.87×10⁹立方米，IR减少6.94×10⁹立方米。本研究为了解中国水稻ET和IR对未来气候变化和二氧化碳浓度升高的响应提供了有益参考，并强调在作物灌溉模拟中必须考虑“二氧化碳施肥效应”。
