近20年东北气候变暖对春玉米生长发育及产量的影响

【目的】探求东北三省近20 年气候变暖对春玉米生长发育进程及产量的影响，为东北地区气候变暖下粮食安全问题提供理论依据。【方法】选取东北黑龙江、吉林和辽宁省三省进行区域研究，利用东北地区近20 年气候观察数据和春玉米长期观测数据，通过相关和回归等数理统计方法系统分析东北三省春玉米生长季的气候因子（温度和降水量）与春玉米生育进程数据和历史产量数据之间的关系。【结果】东北地区1989-2009 年春玉米生长季日最高温度、最低温度以及平均温度均呈明显上升趋势，气候倾向率每年分别为0.050、0.045和0.044℃，表现为春玉米生育期间白天增温幅度较夜间增温幅度大，降水量变化不显著。近20 年黑龙江省各试验站平均播种日期变化趋势是每年提前0.10 d，而吉林省、辽宁省各试验站每年分别推迟0.18和0.21 d。黑龙江省、吉林省以及辽宁省各试验站春玉米平均成熟日期变化趋势分别每年推迟0.39、0.35和0.55 d，平均生育期天数变化趋势分别每年增加0.49、0.17和0.34 d，成熟日期推迟的幅度大于播种日期的推迟幅度导致三省试验站春玉米生育天数增加。对1991-2006 年东北地区审定品种生育期数据与气候数据关系进行相关性分析表明，黑龙江省最高温度（Tmax）上升会延长审定品种生育期，而吉林和辽宁省春玉米的审定品种生育期与平均温度（Tavg）、最高温度（Tmax）和最低温度（Tmin）均呈现为正相关。采用T检验法分析春玉米审定品种生育期和试验站春玉米生育期关系表明，黑龙江和辽宁省的审定品种和试验站春玉米生育天数呈一致的增加趋势，且无显著性差异。采用线性偏回归测验法分析品种和气候因子对春玉米生育期影响重要性的结果表明，品种生育期的延长是导致春玉米生育期不断延长的主要原因。三省春玉米近20 年平均产量表现为增加趋势，其趋势由小到大的次序是辽宁省、吉林省以及黑龙江省，越往北其产量增加趋势越大，产量增加越明显。东北各省地级市1989-2009年面板数据分析表明，东北地区平均温度（Tavg）、最高温度（Tmax）和最低温度（Tmin）的变化均会影响春玉米的产量。温度上升，东北部产量增加明显，尤其是黑龙江省东部的三江平原地区，而东北地区西南部减产。【结论】受气候变暖的影响，东北春玉米品种对气候变暖是逐步适应，可以利用其适应潜力，通过春玉米品种改良和调整播期等措施来适应气候变暖，从而提高春玉米产量。

Impacts of Climate Warming on Growth and Yield of Spring Maize in Recent 20 Years in Northeast China

【Objective】In order to seek the impacts of climate warming on growth process and yield of spring maize in recent 20 years in Northeast China, a study was conducted for providing a theoretical basis for food security.【Method】Three provinces (Heilongjiang, Jilin and Liaoning province) in Northeast China were selected for conducting regional research. Making use of the meteorological observation data and the long-term observation data of spring maize in recent 20 years in Northeast China, the relationships between climate factors (temperature and precipitation) and growth process and historical production data during growing season were analyzed by correlation and regression analysis and other statistical methods.【Result】It was found that the diurnal maximum temperature, minimum temperature and average temperature in Northeast China during spring maize growth season in 1989-2009 were rising significantly. Climate trend rates were 0.050, 0.045 and 0.044 ℃?a-1. During spring maize growth warming amplitude during the daytime was larger than the night. No significant change in the precipitation was found. During 20 years, the change tendency of spring maize average sowing date was 0.10 d in advance every year in experiment stations of Heilongjiang province, but the change tendencies were postponed in experiment stations of Jilin and Liaoning provinces, respectively, 0.18 and 0.21 d per year. The change tendencies of spring maize average maturity date were postponed in experiment stations of Heilongjiang, Liaoning and Jilin provinces, respectively, 0.39, 0.35 and 0.55 d per year. The change tendencies of spring maize average total growth days in Heilongjiang, Jilin and Liaoning provinces were an annual increase of 0.49, 0.17 and 0.34 d, respectively. The amplitude of the delayed maturity date was larger than the delayed sowing date, eventually resulting in increased number of spring maize growth days. The national varieties data and meteorological data correlation analysis in 1991-2006 showed that the rise of the diurnal maximum temperature (Tmax) in Heilongjiang extended national varieties growth period. The correlation between the state-approved varieties growth period and the diurnal maximum temperature (Tmax), minimum temperature (Tmin), average temperature (Tavg) in Jilin and Liaoning provinces showed a positive correlation. Analysis of the relationship between the growth period of the state-approved varieties and experiment station varieties by using T test showed that the growth days of them had a consistent increasing trend in Heilongjiang and Liaoning provinces, and the increasing trend had no significant difference. By adopting linear partial regression test method the importance of varieties and climatic factors on spring maize growth period was analyzed and the results showed that the extension of varieties growth period was the main factor causing experiment station varieties growth period prolonged. The average yield of spring maize showed an increasing trend, and the ascending order of the trend was Liaoning, Jilin and Heilongjiang provinces in recent 20 years. The farther north the yield increasing trend was greater, and the yield increase was more obvious. Panel data analysis showed that changes of the Tavg, Tmax and Tmin affected the yield of spring maize in prefecture-level city of Northeast China in 1989-2009. When the temperature rose, the yield in northeast significantly increased, especially in the Sanjiang plain area of the eastern Heilongjiang province, but the yield in southwest cities was obvious reduced in Northeast China.【Conclusion】Above evidences indicate that spring maize production is affected by climate warming in Northeast China. Spring maize varieties are gradually adapted to climate warming. Varieties improvement and sowing date adjustment for adapting climate warming can improve the yield of spring maize.