黄淮海平原林网保护区夏玉米生长过程的数值模拟

Numerical simulation on maize growth in a regular windbreak system in Huanghuaihai Plain.

利用改进了的产量生态学模型SUCROS ,对黄淮海平原林网保护区夏玉米的生长过程进行了数值模拟 ,并与田间监测资料做了比较 ,分析了影响夏玉米生长的各种生理、生态学因子 .结果表明 ,改进后的模型能成功模拟夏玉米的生长过程 ,考虑病虫害、杂草影响后 ,模型输出的叶面积指数、器官生物量与生长监测资料十分一致 .与单作农田比较 ,由于林网地区小气候条件的改善 ,夏玉米单产提高 6 8%左右 .播种密度、播种日期与籽粒产量关系的数值试验显示该区高产密度标准为 6 75～ 7 5 0 (高肥水田块可达 9 0 0 )株·m-2 ,最佳播种期为5月 2 1日～ 6月 5日 .模拟“凉夏”天气对黄淮海平原南部地区夏玉米生长的影响时发现 ,气温每降低 1℃ ,生育期延长 3～ 4d ,与“低温”伴随的“寡照”是减产的直接原因 .

The modified production ecological model SUCROS was used to simulate the growth process of summer corn with the protection of windbreaks in Huanghuaihai Plain,and the simulated result was compared with the field monitoring data.The effects of various physiological and ecological factors that affect the growth of the summer corn were analyzed.The modified SUCROS could simulate the growth process successfully.The leaf area index and organ biomass simulated by the model could be fairly consistent with the monitoring data when the effects of insect and disease pests and weeds were considered simultaneously.As compared with the simulated data in the monoculture field,the corn yield in the windbreak system was about 6\^8% higher due to the improved microclimate.Based on the simulation of the relationships between sowing density,sowing date and seed production,the density standard for high yield in the region was 6\^75～7\^50 plants·m\+\{-2\},even high as 9\^00 plants·m\+\{-2\} in the fields with sufficient soil nutrients and water supply.It is suggested that the optimal sowing period is from May 21 to June 5.Through simulating the influence of “cool summer”on the growth of summer corn in southern Huanghuaihai Plain,it was found that the growth period of corn would extend 3 to 4 days if the average air temperature during the growing period lowered by one degree.The “less radiation” and correspondent “lower temperature”were the direct reasons of yield reduction in “cool summer”.