基于气候适宜度评价的湖南春玉米优播期分析

Spatial Analysis of Optimum Seeding Time of Spring Maize in Hunan

构建基于Penman-Monteith公式的春玉米适宜度模型,在1981-2010年日气象数据基础上,模拟得出1km格网的研究区春玉米优播期空间分布图。模拟结果表明,大部分地区优播期与初始播期一致,湘南在2月下旬,湘中和湘北大部分地区在3月上旬,比实际播期要早,全区优播期随高程增加而推迟的趋势明显。根据优播期与初播期的关系,研究区可分为三大区:(1)优播期比初播期晚7d左右的湘南盆地地区;(2)优播期比初播期晚2～3周的高海拔地区;(3)优播期与初播期一致的其它地区。优播期的选择需考虑避开成熟期高温和夏秋旱这两个影响因子,由于它们在不同地区存在差异,应具体分析以获得最适宜的春玉米生长条件。

Based on established climatic suitability assessment model and the 1981-2010 daily climatic data,and under the support of geographic information system,a simulation of optimum seeding date of spring maize was carried out in 1km grid mapping unit.The experimental results showed that optimum seeding time is at the third ten days of February in the south of and at the first ten days of Match in most part of middle and north of Hunan province.The optimum seeding time of mountain area gets later along with the height increase.According to the difference between the optimum seeding time and the earliest seeding time,research area can be classified into three sub-regions：（1） the basin in the south where the optimum seeding time is 2 weeks later than the earliest seeding time.（2） High mountain sub-region where the optimum seeding time comes 2～3 weeks later.（3） The other part where the optimum seeding time is identical with the earliest seeding time.The determination of optimum seeding time needs to take into consideration of damages from high temperature damage in maturing stage and the deficit of water in the later growth period,as they varies spatially,the optimum seeding time determination need to be analyzed for different site specifically.