近50年华北地区冬小麦低温灾害的时空演变特征  

Spatial-temporal change of low temperature disaster of winter wheat in North China in last 50 years

作　　者：钱永兰 王建林 郑昌玲 杨霏云[2] 宋艳玲[3] 宋迎波 

机构地区：[1]国家气象中心,北京100081 [2]中国气象局气象干部培训学院,北京100081 [3]国家气候中心,北京100081

出　　处：《生态学杂志》2014年第12期3245-3253,共9页Chinese Journal of Ecology

基　　金：公益性行业科研专项(GYHY201106021)资助

摘　　要：低温灾害是华北地区冬小麦的主要灾害之一,全生育期内均可发生。本文基于气象站逐日最低气温和华北各地冬小麦不同发育阶段低温灾害的界限温度,对华北地区近50a冬小麦低温灾害进行定量反演,分析其演变特征。结果表明：近50 a华北地区冬小麦生长季内低温灾害的频次和强度均呈现随年代递减的总体趋势,全生育期的低温灾害天数由20世纪60年代的平均50 d以上降至21世纪前10年的不足40 d,低温灾害指数则由0.6以上普遍降至0.4以下;其时空演变特征表现为,华北东部变速快于西部,近20 a变速快于前30 a;在冬小麦不同发育阶段,低温灾害频次的变化趋势也存在明显差异,在冬小麦越冬和返青阶段低温灾害的发生频次呈现明显随年代递减趋势,而冬小麦分蘖、拔节、抽穗等发育阶段低温灾害的发生频次则一直维持较高水平;近50 a华北地区冬小麦发生低温灾害的日最低气温平均上升了1~2℃,但同期发生低温灾害的极端值则无明显年代际变化。Low temperature disaster is one of the major disasters of winter wheat in North China,which could occur at its every growth stage. In this paper,low temperature disaster of winter wheat was identified based on daily minimum air temperature and injury threshold at different growth stages of winter wheat in North China in last 50 years,then the spatial-temporal change characteristics of the disaster were analyzed. The results showed that,in last 50 years,both the severity and frequency of the low temperature disaster of winter wheat in North China decreased along with decadal-scale variation. The severity index of the disaster decreased from more than0. 6 in the 1960 s to less than 0. 4 in the 2000 s,and the frequency of the disaster reduced from more than 50 days in the 1960 s to less than 40 days in the 2000 s. As to spatial-temporal change pattern of the disaster in North China,both the severity and frequency in the eastern region decreased faster than in the western region,and more rapidly in recent 20 years than in the former30 years. At the different growth stages of winter wheat,the change tendency of the disaster frequency was obviously different. At the over-wintering stage and turning-green stage,the frequency of low temperature disaster was reduced rapidly at decadal scale,but it occurred unchangeably at high levels at the stages of tillering,jointing and head sprouting. The mean of daily minimum air temperatures when winter wheat suffered the low temperature disaster rose about 1-2 ℃ during the last 50 years in North China,but there was no clear trend of decrease in the extreme value of the disaster occurring in the same growth stage.

关 键 词：冬小麦 冻害 霜冻 华北 气候变化 

分 类 号：S512.11[农业科学—作物学] S426