福建省基于自适应调整的水稻生产对未来气候变化的响应

将福建省划分为3 个稻区, 共选取17 个样点和9 个代表性品种开展气候变化影响评价研究。首先, 根据IPCC排放情景特别报告(SRES)中的A2、B2、A1B 三种方案和区域气候模式(PRECIS), 生成了研究区域两个时段(1961-1990 年, 2021-2050 年)的气候变化情景; 然后, 采用经验证的CERES-Rice 模型, 模拟分析了福建省各稻区在未来不同气候变化情景下可能的稻作制度、品种搭配及水稻播期, 并认为这是水稻生产自适应调整后的结果; 接着, 以调整后的稻作制度、品种搭配及水稻播期作为CERES-Rice 模型新的输入, 在3 种气候变化情景下再次进行模拟试验, 最后得出未来经过自适应调整后的水稻产量、稳产性以及全省水稻总产的变化。结果表明: 在A2、B2、A1B 三种气候变化情景下, 闽东南双季稻区的早稻模拟产量经自适应调整后, 较之不考虑这种调整依次提高了15.9%、18.0%和19.2%, 后季稻依次提高了9.2%、7.4%和7.4%; 闽西北双季稻区的早稻模拟产量依次提高了21.2%、20.5%和18.9%, 后季稻依次提高了14.7%、14.8%和7.2%。考虑自适应调整后, 闽西北山地单季稻区的水稻模拟产量在A2、B2、A1B 情景下, 较之不考虑这种调整依次增产4.9%、5.0%和2.9%, 其中长汀在A2 与B2 情景下可改种双季稻。在综合考虑水稻生产自适应调整后, 福建省水稻模拟总产表现为增产, 在A2、B2 与A1B 情景下较之当前依次增加5.9%、5.2%和5.1%。因此,在气候变化影响评价研究中, 将水稻生产的自适应能力考虑在内, 不仅科学合理, 而且可以得到较为乐观的结论。

Response of Rice Production Based on Self-Adaption to Climate Change in Fujian Province

The goal of this study is to take the self-adaption of rice production in future into consideration in the climate change impact studies, to enhance its rationality. The first step we did was to classify Fujian Province into three rice regions according to the topographic features and rice-based cropping systems. Altogether 17 sites and 9 representative rice varieties with different maturity types were selected to conduct the simulation experiments. The second step, to generate climate change scenarios in two periods (1961–1990 and 2021–2050), based on three emission schemes (A2, B2, and A1B) in IPCC Special Report (SRES), combined with the Regional Climate Model of PRECIS. The third step to run CERES-Rice model under the three climate change scenarios to simulate the influence of future climate change on rice production in Fujian Province, without considering the self-adaption of rice production. The direct effects of CO2 enrichment on photosynthesis and transpirations were also included.The forth step, to assess the possible change in rice-based cropping system, varietal type as well as sowing date in future in the studied area, based on the simulated results and some climatic indices, and these changes could be regarded as the results of self-adaption adjustment in future. The fifth step, to run CERES-Rice model again under the three climate change scenarios using the possible cropping systems, varietal types and sowing dates after self-adaption adjustment. Finally, to assess change in rice yield, yield stability in different rice regions and the overall output of rice in the province in future with considering the self-adaption adjustment. The results indicated that the simulated yields of early rice in the Double Rice Region in southeastern Fujian under A2, B2, and A1B scenarios increase by 15.9%, 18.0%, and 19.2% and that of late rice increase respectively by 9.2%, 7.4%, and 7.4% when the self-adaption adjustment was considered, compared without consideration. In the Double Rice Region in Northwestern Fujian, the simulated yields of early rice increase by 21.2%, 20.5%, 18.9% and that of late rice increase respectively by 14.7%, 14.8%, and 7.2% under the three climate change scenarios when the self-adaption was considered, compared with without consideration. Similar results could be obtained in the Single Rice Region in the mountain areas of Northwestern Fujian. The simulated yields of single rice increase respectively by 4.9%, 5.0%, and 2.9% under the three scenarios, comparing the two cases with and without consideration of self-adaption. In this rice region, double rice might be grown in future in the site of Changting under the A1 and B2 scenarios. When the self-adaption adjustment was considered, the overall output of rice crop in Fujian Province under the three climate change scenarios would increase by 5.9%, 5.2%, and 5.1%, respectively. It is concluded that more optimistic results could be obtained when self-adaption ability of food production was taken into consideration.