关键词: 连香树, 土壤理化性质, 气候, 海拔

Abstract: Drought is one of the most serious agricultural meteorological disasters, and the main limiting factor for raising winter wheat yield in North China. Through analyzing the decrease rate and variation coefficient of winter wheat yield and the occurrence probability of drought, this paper established a risk assessment model of winter wheat drought loss, and completed the risk regionalization of this loss in North China. The results indicated that the high risk area located in the west, northwest and southwest of Shandong Province, northeast of Hebei Province, and east of Henan Province, the medium risk area located in the middle and south of Hebei Province, north, middle and west of Henan Province, and middle hilly areas of Shandong Province, and the low risk area located in the middle and south of Shandong Province, and south and south-west of Henan Province, accounting for 19.8%， 34%, and 46.2% of the whole North China, respectively.

Key words: Cercidiphyllum japonicum, Chemical and physical characteristics in soil, Climate, Elevation