通过模拟计算得到一级生产水平下冬小麦和夏玉米的累积干物质动态曲线 .两年的计算结果和实测值都比较吻合 .研究表明 ,在黄淮海平原 ,可以把亩产吨粮作为冬小麦 夏玉米一年两茬平作粮田达到一级生产水平的指标 .若用中熟夏玉米套作代替早熟夏玉米平作 ,籽粒的年产量可增加一成 .通过对不同叶面积指数下干物质产量的模拟计算 ,得到一年两茬平作的干物质产量最大可达 46t·hm- 2 ,籽粒产量 1 9.1t·hm- 2 . The dynamic curve of cumulative dry matter yield of winter wheat and summer maize under the first-level production level was obtained through simulation calculation.The calculated results of the two years are in good agreement with the measured values.The study shows that in the Huang-Huai-Hai Plain, Cropping cropland for one year to achieve the level of the first level indicators.If the medium-maturing summer maize sets instead of early maturing summer corn, grain yield can be increased by 10% .According to different leaf area index of dry matter production simulation According to the calculation, the maximum yield of dry matter reached 46 t · hm-2 and the grain yield was 9.11 · hm-2 in two crops per year.