摘要
在南方红壤区,分阴、晴两种天气条件,分别模拟不同施氮水平(0、120和240kg.hm-2)的夏玉米水分胁迫指数(CWSI)下基线方程。结果表明,阴天时由于空气饱和差集中于1～1.25kPa,不适合模拟玉米CWSI下基线,而在晴天时,尽管空气饱和差在1～3kPa范围内变化,但是模拟建立的CWSI下基线回归检验效果极显著(P<0.01);晴天条件下,在相同空气饱和差变动范围内,有氮素供给的夏玉米冠气温差低于不施氮的,而且随着施氮量的增多,冠气温差逐渐降低,从而导致不同施氮水平处理夏玉米CWSI下基线各不相同。试验结果表明,在南方红壤区亚热带季风气候条件下,可以在晴天时建立作物CWSI下基线;并且在使用CWSI时,要根据作物施肥水平建立相应的CWSI下基线。
The low baseline of summer maize water stress index with different N level treatments （0,120 and 240kg ~ ha- 1 ） in red soil in south China under sunny and cloudy conditions was established. The results showed that the regres- sion testing effects were significant（ P 〈 0. 01 ）. Nitrogen fertilization had reduced low baseline of maize. The low base- line decreased with nitrogen fertilization increased. The results indicated that CWSI could be used to detect water status in red soil, where the climate type is subtropical monsoon. So the low baseline of maize could be defined in sunny con- dition in this region. The results also suggested that the low baseline of CWSI should be defined at comparable soil ferti- lization levels in specific region.
出处
《中国农业气象》
CSCD
北大核心
2012年第2期215-219,225,共6页
Chinese Journal of Agrometeorology
基金
国家自然科学基金项目(40871139)
国家"十一五"科技支撑计划项目(2009BADC6B01)
关键词
红壤
氮肥
夏玉米
作物水分胁迫指数
下基线
Red soil
Nitrogen fertilization
Summer maize
Crop water stress index
Low baseline
