东北地区单季稻温度适宜性及其变化特征

Temperature suitability of rice and its variation in Northeast China

利用温度适宜度模型计算了1961—2015年东北地区单季稻各生育阶段温度适宜度,并对其平均值、变异系数及时空分布和变化特征进行了分析。结果表明:东北地区单季稻分蘖、孕穗和抽穗期温度适宜度高且变异系数小,而播种和出苗期则相反;根据各站点55年平均适宜度大小,将东北单季稻主产区划为适宜度高、中、低3个区,且适宜度高低在空间上存在较明显的南北差异,总体随纬度的增加而减小;1961—2015年单季稻各生育阶段温度适宜度均表现为先下降后上升、总体升高的趋势,播种-出苗、乳熟-成熟阶段升高趋势最为明显(尤其在20世纪90年代中期以后);根据东北地区各站点温度适宜度变化倾向率,将东北地区单季稻主产区分为适宜度强增长、次增长和弱增长区,强增长区主要位于温度低适宜区,未来东北地区单季稻温度适宜度的地域性差异将减小,种植环境将趋于平均和优化。

Based on the temperature suitability model,this paper calculated the temperature suitability of rice at different growth stages,and evaluated the mean value and coefficient of variation and the spatiotemporal distribution and change pattern of temperature suitability of rice in Northeast China during 1961-2015. The results showed that the temperature suitability was high with low variability at tillering,booting and heading stages. On the contrary,the suitability was low with high variability during sowing and seeding stages. On the basis of the average temperature suitability of each station during the study period,the main production area of rice in Northeast China was divi-ded into three regions with high,medium,and low suitability,respectively. Spatially,there was a significant north-south difference in suitability,and the suitability generally decreased with the increase of latitude. Temperature suitability of each developmental stage decreased firstly and then increased,and showed an increased tendency in general from 1961 to2015. Besides,such increasing trend was most significant from sowing to seeding stage and milky to mature stage,especially after the mid-1990 s. According to the rate of linear tendency of temperature suitability of each station,the main production area of rice in Northeast China was divided into three regions with high,moderate and low increase in temperature suitability,respectively. Our analysis suggests that the planting environment of rice in Northeast China will be improved,since the lower temperature suitability region would be always companied with a higher tendency of increase in temperature suitability and the regional differences would get smaller.