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Analizirali smo živi arhiv metasekvoje (Metasequoia glyptostroboides Hu et Cheng) na obrečnem rastišču ob Savi pri Ljubljani. Osnovan je bil v letih 1993 in 1994 s sadikami, vzgojenimi iz originalnih semen z območja na Kitajskem, kjer je bila vrsta opisana (klasično nahajališče oz. locus classicus). Drevesa v nasadu so bila prvič izmerjena spomladi leta 2000 in nato še leta 2006, spomladi v letu 2020 pa smo meritve ponovili. V starosti 30 let je povprečno drevo merilo v višino 20,7 m, povprečni premer koreninskega vratu na višini debla 0,1 m je znašal 72,3 cm, povprečni premer debla na prsni višini pa 51,4 cm. Ugotovili smo, da je pogostnost reproduktivnih organov, torej storžev in moških cvetov, povezana s premerom in višino drevesa. Užlebljenost debla je zelo variabilna in povezana s premerom, zelo variabilno je tudi zmanjšanje premera z višino. Povezave med omenjenimi znaki in lego drevesa v nasadu nismo ugotovili. Svetloba oziroma lega v nasadu ni edini dejavnik, ki vpliva na lastnosti posameznega drevesa, vzrok je tudi genetska variabilnost med drevesi. The live archive of dawn redwood (Metasequoia glyptostroboides Hu et Cheng) on a riparian site of river Sava near Ljubljana, which was established in 1993 and 1994, has been analyzed. The trees have been grown from original seeds from an area in China where it was first described (locus classicus). The measurements of all trees on the plantation were carried out in 2000 and 2006. For the purpose of this research, they were taken again in 2020, and the latest data has been analyzed. The average tree height of 30-year-old trees was 20.7 m, the average tree diameter 10 cm above root crown was 72.3 cm and the average tree breast height diameter was 51.4 cm. It has been found that the incidence of reproductive organs, such as cones and male strobili, correlates to the diameter and height of trees, but not to the position on the plantation. The trunks’ ridges do not depend on the position in the plantation however they vary significantly among trees. The light and the position on the plantation are not the only factors affecting the characteristics of individual trees, the reason is also the genetic variability of trees. |
