内蒙古地区紫花苜蓿融冻型冻害的时空动态

Spatial-temporal Characteristics of Alfalfa Thawing-freezing Injury in Inner Mongolia

以内蒙古地区紫花苜蓿为对象,利用R语言与MySQL数据库工具,在构建基于日值的紫花苜蓿萌动过程与融冻型冻害等级数据库的基础上,采取薄板平滑样条函数等GIS空间分析手段并结合典型站点时间序列的小波分析,阐述1951~2016年间内蒙古地区紫花苜蓿萌动过程和融冻型冻害强度的时空动态特征。研究表明,内蒙古紫花苜蓿融冻型冻害表现为空间上局地高发、时间上总体减少与局地增加并存的态势,东阿拉善、乌海、河套地区和鄂尔多斯西部属于高发区,乌兰察布、赤峰南部为缓发区。近65年来,随着气候变暖,高发区融冻型冻害发生的频率降低,总强度呈现出渐变式显著减小的变化趋势;缓发区以及锡林郭勒、兴安盟、呼伦贝尔等地区,融冻型冻害风险增大。

The thawing-freezing injury（TFI）influences the alfalfa reviving rate seriously in the north of China.Focusing on the alfalfa in Inner Mongolia,the R-Language and the MySQL database were used,a daily database containing sprouting phase and TFI grade of alfalfa was built.The spatial-temporal characteristics of both alfalfa sprouting phase and it＇s TFI density in 1951-2016 were clarified by employing the GIS spatial analysis technology,such as thin plate smooth spline function and the wavelet analysis on representative stations.The results showed that the TFI showed a high possibility in certain regions in the space,and decrease overall while it was increasing in a few regions in the time.The high-incidence regions were eastern Alashan,Wuhai,Hetao region,western Ordos,the secondary-incidence region were the south of Ulanqab and Chifeng.In the recent 65 years,under the background of climate warming the frequency of TFI density gradually decreased in the high-incidence regions.The TFI risk increased in Xilingol,Xinganmeng,Hulunbuir and the secondary-incidence regions.