未来30a凉山州水稻盛夏低温危害风险分析

根据(BCC)气候系统模式第五阶段试验计划(CMIP5-RCP6.0)预测的2006~2050年各格点逐日平均温度,通过订正反演出2021~2050年凉山州各站点逐日平均温度,结合凉山州不同区域水稻抽穗杨花期低温指标,统计了各站水稻盛夏低温频次、水稻安全播种期、安全齐穗期以及安全生长季差,构建了水稻盛夏低温危害风险指数I=exp(Id+ip-2),并以此进行低温危害风险的区域划分,结果表明:(1)凉山州水稻盛夏低温频次为0.1~3.0次/a,在区域和年际之间差异很大;(2)与近30a比较,凉山州水稻安全播种期普遍提前10 d左右,提前最多的达20 d以上。安全齐穗期只有少数站点推迟,大多数站点都有提前的趋势;(3)海拔1 500 m以下为无风险区,1 500~2 000 m的区域为低风险区,2 000~2 500 m为中风险区,2 500~2 600 m为高风险区,分区结果与实际情况相符,为凉山州未来水稻生产布局、应对气候变化的影响提供科学依据。

ANALYSIS ON MIDSUMMER LOW TEMPERATURE DAMAGE RISK OF RICE IN LIANGSHAN PREFECTURE IN THE NEXT 30 YEARS

According to daily average temperature predicted by the stage 5 test plan (CMIP5-RCP6.0) of the climate system model (BCC) at each lattice point in 2006-2050, we corrected and inverted the daily average temperature of every site of the Liangshan prefecture from 2021 to 2050. Using the low temperature index of different areas of Liangshang prefecture during rice heading and flowering, we analyzed the mid summer low temperatue frequency and the security sowing date and the security full heading date, and the days from sowing security date to full heading security date. We also established a risk index of mid summer low temperature on the rice such as I=exp(Id+Ip-2). According to the risk index, the Liangshan prefecture were divided into different areas of low temperature risk. The results showed that:(1) the mid summer low temperature frequency of Liangshan was between 10% and 300%, and the regional and interannual differences were very large; (2) Compared with the past 30 years, generally, the security sowing date of rice was advanced by about 10d,the most advance was more than 20d in the Liangshan prefecture. Only at a few sites the security full heading date was delayed, while most sites had a advanced tendency. (3) The areas at an altitude below 1500 m had no such risk, while the 1500-2000m areas were lower-risk areas, 2000-2500m were medium risk areas, 2500-2600 m were high risk areas. The partition results are ine line with the actual product of rice in the Liangshan Prefecture, and provided a scientific basis for future rice production layout in response to climate change.