未来气候变化对四川盆地玉米生育期气候资源及生产潜力的影响

Impact of future climate change on climatic resources and potential productivity of maize in Sichuan Basin

开展气候变化背景下四川盆地玉米生育期气候资源及生产潜力时空变化趋势的预估，可对未来应对气候变化及玉米生产宏观决策提供重要的理论依据。利用区域气候模式PRECIS输出的未来A2和B2气候情景（20712100年）及基准气候条件（19611990年）气象要素资料，分析了四川盆地玉米生育期内主要气候资源（日平均气温≥10℃积温、日照时教、降水量、参考作物蒸散量和缺水率）和玉米生产潜力（光合、光温和气候生产潜力）时空变化特征。结果表明，与基准气候条件相比，在A2和B2两种气候情景F．2071-2100年四川盆地玉米生育期内≥10℃积温、日照时数和参考作物蒸散量都呈增加趋势；两种气候情景下，日平均气温≥10℃积温的增量分别为460-64l℃·d和376～492℃·d，在盆地西部增量最大；日照时数的增量分别为15-225h和33~202h，雅安增加最多；参考作物蒸散量的增量分别为76～144mln和73～123mm，雅安增加最多。降水量在大部分地区呈减少趋势，变幅分别为-87～56mm和-73～47mm，雅安减少最多。玉米缺水率分别增加2％～18％和5％-16％，雅安增幅最大，未来四川盆地玉米受干旱灾害的风险可能加大。在A2和B2情景下，2071--2100年玉米光合生产潜力分别增加228-3277kg·hm之和485～2960kg·hm2，雅安和川北部分地区增量最大；光温生产潜力也呈增加趋势，分别增加2923～5874kg·hm屯和2697～4909kg．hm2，雅安的增量最大；气候生产潜力同样呈增加趋势，分别增加984～2975kg·hm-2和293～2090kg．hm，盆地西部增加较多。未来四川盆地气候资源变化对玉米的生产有利，产量存在提升空间。

Maize is a major cultivated grain crop in Sichuan and has contributed significantly to total grain production in the province. Sichuan Province has a complex topography and various landforms where climate change has caused temperature and precipitation anomalies, adversely affecting local maize production in the past 50 years. However, studies of future changes in agricullural climatic resources and COiTesponding impacts on maize production in Sichuan have rarely bcc reported. Predicting temporal and spatial changes in climatic resources and potential productivity during the entire growth period of maize under global climate change in the Sichuan Basin can lay key theoretical basis for developing response strategies of climate change and macroscopic policy decisions on maize production. Based on baseline climatic condition climate scenarios （2071-2100） from the PRECIS regional climate model, the spatial and temporal characteristics of climatic resources （accumulated temperature of daily average temperature, sunshine hours, precipitation, reference crop evapotran spiration and water deficient ratio） and potential productivity （photosynthetic potential productivity, photo-temperature potential productivity and climatic potential productivity） of maize in Sichuan Basin were analyzed. The results showed that accumulated temperature sunshine hours and reference crop evapotranspiration ：luring the entire growth period of maize increased in 2071-2100 under A2 and B2 climate scenarios compared with the 1961-1990 baseline climate conditions. Accumulated temperature increased respectively by 460-641 d and 376-492 d under A2 and B2 climate scenarios with the highest increase in the western basin. Sunshine hours would increased respectively by 15-225 b and 33-202 h, with the highest increase in Ya＇an. Reference crop evapotranspiration increased respectively by 76-144 mm and 73-123 mm with the highest increase in Ya＇an. Precipitation decreased in most of the regions of Sichuan Basin with the highest decrease in Ya＇an. For individual region, however, precipitation apparently respectively increased within 87-56 mm and 73-47 mm under the A2 and B2 climate scenarios. Water deficient ratio of maize respectively increased by 2%-18% and 5%-16% under the future A2 and B2 climate scenarios, suggesting increasing maize drought disaster risks in Sichuan Basin. Compared with the 1961-1990 baseline climate conditions, photosynthetic potential productivity of maize respectively increased by 228-3 277 kg.hm-：： and 485-2 960 kg＇hm 2 during 2071-2100 under A2 and B2 climate scenarios with the highest increase in Ya＇an and northern basin. Photo-temperature potential productivity respectively increased by 2 923-5 874 kg.hm 2 and 2 697-4 909 kg-hm-2 during 2071-21 00 under A2 and B2 climate scenarios with the highest increase in Ya＇an. Climatic potential productivity respectively increased by 984-2 975 kg.hm-2 and 293-2 090 kg＇hm-2 during 2071-2100 under A2 and B2 climate scenarios with the highest increase in western basin. Future changes in climatic resources were apparently beneficial to maize yield in Sichuan Basin.