Phenological characteristics of herbaceous plants in Hebei Province and their responses to climate warming
Based on the herbaceous plants phenological observation data of 8 National agro-mete-orological observation stations and the ground observation data of 47 meteorological stations in He-bei Province from 1981 to 2006, and by using EOF and REOF methods, this Paper analyzed the phenological characteristics of herbaceous plants in this Province and the responses of the plants to climate warming. In 1981-2006, the herbaceous plants in the Province had an overall advan-cing trend in their first leafing date, and the trend was most obvious in the eastern coastal plain, followed by in the central-southern plain, and in the northwest mountain region. The first wither-ing date of the herbaceous plants delayed, and the growth season extended. The air temperature in spring had significant effects on the first leafing date, I. E. , when the air temperature increased by 1 ℃ , the first leafing date was advanced by 4.1 days. There was a significant positive correla-tion between the growth season trend and the mean annual air temperature, I. E. , the greater the increment of mean annual air temperature, the greater the increment of growth season extension. The phenological characteristics of herbaceous plants and their responses to climate change were similar to those of woody plants. This study would be helpful to the evaluation of the relationships between phenology and climate change in Hebei Province.
herbaceous plantphenologyfirst leafing dateair temperature in springclimate warming