民勤荒漠区植物物候型特征及其与气温的关系

Phenological characteristics in Minqin desert area and their relationships with air temperature

对民勤荒漠区34年的物候观测资料进行了物候型分析。结果表明:植物的萌动期有2种物候型,展叶期和开花期各有4种物候型,果熟期有2种物候型,1974年以来,当地年平均气温和2、3、6月月平均气温有较显著的增温趋势,与此同时,植物的春季物候期亦有明显的提前趋势,低温-短日照-早萌动物候型的芽膨大期34年提前了9.7d;从萌动期→展叶期→开花期→果熟期,物候期的提前幅度逐渐减小;物候期提前主要与当月气温升高有关;萌动期2种物候型和展叶期4种物候型是植物对春季气温和秋末冬初气温适应性的分异,开花期4种物候型和果熟期2种物候型是植物花期多样性和果熟期多样性对当地干旱环境适应性的反应。

The analysis on the phenological characteristics in Minqin desert area based on 34 years phenological observation data showed that there were 2 phenological types in bourgeon period, 4 phenological types in leaf expansion period, 4 phenological types in flowering period, and 2 phenological types in fruit ripeness period. Since 1974, the mean annual air temperature and the mean monthly air temperature of February, March, and June in the area had a significant warming trend, and the phenology of plants in spring also had an evident advance trend. The bud expanding period of the phenological type ‘low temperature - short sunshine - early budded＇ advanced 9.7 days. From bourgeon period to leaf expansion period, to flowering period, and to fruit ripeness period, the magnitude of phenological advance reduced gradually. The advance of phenology was related with the rising temperature of current month. Two phenological types in bourgeon period and 4 phenological types in leaf expansion period were the differentiation of the adaptation of plants to the air temperature in spring and late fall, while four phenological types in flowering period and 2 phenological types in fruit ripening period were the adaptive responses of the diversities of plant＇ s flowering period and fruit-ripening period to the local drought environment.