Populaciona i individualna varijabilnost fenofaze listanja lužnjaka u tri sukcesivne godine
Population and individual variability of the leafing phenophase of pedunculate oak in three successive years
Abstract:
The leafing phenophase of pedunculate oak (Quercus robur L.) was analyzed at two locations in Belgrade (Ada Ciganlija - 'AC', Bojčinska šuma - 'BS'). The observations were made on 29 trees per site for three consecutive years (2004, 2005, 2006). In the 'BS' site the phenophase of leafing starts and ends earlier than in the 'AC' site. The largest number of trees in the 'AC' site are classified in the late phenological group and in the 'BS' site they belong to the 'average' group. Population variability of the analyzed parameters of the phenophase of leafing was confirmed by the results of a Mann - Witney U - test for each year of observation, except for the end of the second year of observation and start of leafing in the first year of observation. According to the results of an F - test significant differences between sites were confirmed for all analyzed parameters except for the duration of leafing (2005) and the start of leafing (2006). Differences among the years of observation in the 'AC' site were significant only in the end and in the 'BS' site for they were significant for all three growth stages of scrolling. Despite the different environmental conditions in the three years of monitoring the stability of the phenology of analyzed populations was maintained (the percentage of trees that were always over the years of observation in the same phenological group relative to the start of leafing 'AC' - 41.3%, 'BS' - 55.2%), which is primarily the result of the genetic structure of populations and intraspecies variability.