摘要
对10个杨树品种的8个物候期进行了观测研究,结果表明,在甘肃靖远,各品种物候期有很大差异,叶黄始期最为明显,极差达46d;其次为叶黄盛期和落叶始期,极差为45d;差异最小的为展叶期,极差仅为8d。不同品种杨树生长期长短不一,影响杨树生长期长短的物候因素主要是后期的叶黄始期、叶黄盛期、落叶始期、落叶盛期等4项的差异程度。运用主成分分析法将物候期分为三类:前生长因子、后生长因子、落叶因子。这三类因子分别以芽萌动期、封顶期、叶黄盛期为典型代表。
Have observed 8 phenological stages of 10 varieties of Populus in Jingyuan county of Gansu province. The result showed:there is a big difference in phenological stages among 10 varieties of Populus, the stage of leaves beginning yellowing is most obvious and its extreme day-difference is 46d; the second are the stage of leaves most yellowing and leaves beginning falling, its difference is 45d; the stage with minimum difference is leaves unfolding and its extreme day-difference is only 8 d. Different Populus varieties have different growth period, and its main influcing factors of phenological are the staage of leaves beginning yellowing, stage of leaves most yellowing, leaves beginning falling and leaves most falling. Divided phenological stage as previous growth factor, posterior growth factor and leaves-falling factor by applying main component analysis method.
出处
《甘肃林业科技》
2005年第2期29-31,45,共4页
Journal of Gansu Forestry Science and Technology
关键词
杨树品种
物候期
主成分分析
Populus
phonological stage
analysis of main component
