Guangyuan city belongs to subtropical humid monsoon climate. The annual rainfall is 800- 1000 mm, sunshine hours are 1300- 1400 hours, and the annual average temperature is about 17℃. Guangyuan, located at the southern foot of the Qinling Mountains, is a transitional zone between the north and the south, with the characteristics of humid climate in the south, high sky and light clouds in the north and bright sunshine. Low mountains in the south and hot in Leng Xia in the east; Donghan is a mountainous area in the north, with cool summer and rapid cooling in autumn. Annual average temperature 16. 1, July temperature 26. 1, 1 monthly temperature 4.9. Average annual rainfall 108 mm, daily rainfall 1398.0 hours, frost-free period of 264.5 days, four distinct seasons, suitable for biological reproduction. However, natural disasters, especially droughts and floods, occur frequently.