气候变暖对江西双季早稻适播期的影响

利用江西省82个气象观测站1971-2012年地面气象观测资料和14个农业气象观测站1981-2012年双季水稻物候观测资料，针对气候变暖对江西省稳定通过10℃初日、20℃终日以及双季水稻生育期热量条件的影响，依据双季水稻熟性搭配种植对热量条件的需求，采用倒推法计算不同年代以及13个30 a滑动平均序列的双季早稻适播期，分析双季早稻适播期起止日期与持续日数的变化特征。结果表明：10℃初日总体呈提前趋势，尤其是2001年以后，大幅度提前；不同年代间20℃终日的变化幅度较10℃初日的小；适播期起始日期大部分站点呈“推迟-推迟-大幅提前”的趋势，终止日期大部分站点呈“推迟-提前-大幅推迟”的趋势，持续日数一般呈“增加-减少-大幅增加”变化趋势。受气候变暖的影响，江西省适宜采用“中熟＋中熟”搭配方式种植双季水稻的地区逐步北扩，尤其是2001年以后，可采取“中熟＋中熟”搭配方式的地区明显扩大。1981-2010年江西省除修水县、铜鼓县、资溪县等局部地区外，大部地区可采取“中熟＋中熟”搭配方式。1991-2020年，除了修水、婺源等赣北局部地区种植仍有一定风险外，其余地区的热量条件均满足“中熟＋中熟”搭配方式的双季水稻种植，或采取对热量条件要求更高的熟性搭配方式种植，如南昌县、樟树市等地可调整为“中熟＋迟熟”或“迟熟＋中熟”搭配方式，而泰和县、南康县、龙南县等地可因地制宜采取“迟熟＋迟熟”搭配方式种植双季水稻，以充分利用热量资源，提高双季水稻产量与品质。

Impact of Climate Warming on Optimum Sowing Period of Double-cropping Early Rice in Jiangxi

The beginning date of 10 ℃, the end date of 20 ℃ and the heat resources during the growth period of double cropping rice in Jiangxi province have changed obviously due to the climate warming. According to the heat condition demand of double cropping rice production, the backward algorithm was employed to analyze the decadal variation and the 13 30-years moving average sequences of optimum sowing period of double cropping early rice in Jiangxi based on the 1971-2012 observed meteorological data and growth period data of double cropping rice during the period of 1981-2012 from 14 agro meteorological stations. The results showed that the beginning date of 10 ℃ showed a tendency to advance in age, especially after 2001. The decadal end date of 20 ℃was relatively stable. The beginning date and the end date of optimum sowing period showed tendencies of “delayed - delayed -advanced significantly”and“delayed-advanced-delayed significantly”respectively, while the duration of optimum sowing period showed a tendency of “increased-decreased-increased significantly”. Under the background of climate warming, the region suitable f or“medium＋medium”ripening cultivars of double cropping expanded northward step by step, and it had broadened out evidently after 2001. In most area of Jiangxi,“medium＋medium”ripening cultivars of double cropping could be adopted during 1981-2010, except for the regions as Xiushui, Wuyuan, Hukou and Yifeng. In the period of 1991-2020, there was still certain risk to take“medium＋ medium” ripening cultivars of double cropping in some regions in northern Jiangxi, such as Xiushui and Wuyuan, while the rest will be suitable to adopt “medium ＋ medium” ripening cultivars of double cropping. Moreover, in Nanchang and Zhangshu, there could adjust to“medium ＋ late” or“late ＋ medium” ripening cultivars of double cropping, and in Taihe, Nankang and Longnan, there could take“late ＋ late” in order to make full use of heat resources.