Jato Victoria, Rodríguez-Rajo F Javier, Aira M Jesús
Department of Plant Biology and Soil Sciences, Campus As Lagoas Ourense, University of Vigo, 32004 Ourense, Spain.
Ann Agric Environ Med. 2007;14(2):271-80.
Although aerobiological data are frequently used as a flowering sign in phenological research, airborne pollen counts are influenced by a number of factors affecting pollen curves. A study was made about the reproductive biology of birch and environmental factors influencing its pollen release and transport, in order to achieve a reliable interpretation of Betula pollen curves. Aerobiological data were recorded in 2002 and 2003 at two sites in NW Spain and phenological observations were carried out on 20 trees from four Betula populations (three Betula alba L. and one B. pendula Roth.). Pollen production was calculated for six Betula alba trees. Chilling and heat requirements for triggering development were calculated. Due to differences in the geographical location, budbreak and flowering started first in Betula pendula. The flowering period lasted from 8-13 days. Reduced pollen output per anther and catkin in individual trees in 2003 prompted a marked decline in overall pollen production. Major differences observed in birch pollen curves were attributed to the influence both of weather conditions and pollen transport from areas where the flowering occurs at a different time. Heat requirements calculated using phenological and aerobiological data were similar when the peak pollen-count date was used.
虽然空气生物学数据在物候学研究中常被用作开花标志，但空气中花粉计数受多种影响花粉曲线的因素制约。开展了一项关于桦树繁殖生物学以及影响其花粉释放和传播的环境因素的研究，以便对桦木属花粉曲线作出可靠解读。2002年和2003年在西班牙西北部的两个地点记录了空气生物学数据，并对来自四个桦木种群（三个欧洲白桦和一个垂枝桦）的20棵树进行了物候观测。计算了六棵欧洲白桦树的花粉产量。计算了触发发育所需的低温和高温条件。由于地理位置的差异，垂枝桦的芽萌动和开花最早开始。花期持续8 - 13天。2003年单株树木花药和柔荑花序的花粉产量减少，导致总体花粉产量显著下降。桦树花粉曲线中观察到的主要差异归因于天气条件以及来自开花时间不同地区的花粉传播的影响。当使用花粉计数峰值日期时，利用物候学和空气生物学数据计算出的热量需求相似。
