Morphophysiological Differentiation of Siberian Stone Pine at the Timberline in Central Altai

Morphologische Differenzierung von sibirischer Zirbe an der Waldgrenze in Altai

Wien

2002

1 Abb., 2 Tab., 8 Lit. Ang.

Unselbständiges Werk

627

200097820

Morphological characteristics of crown and shoots, cone and seed traits and a set of structure and functional needle characteristics were measured in two stands of Siberian stone pine (Pinus sibirica Du Tour): subalpine (1700 m asl) and timberline (2000 m asl). At the upper elevation decreasing of branching come about from rare emergence of summer shoots and reduction of activity their organogenesis. Also, the influence of secondary morphogenesis on crown formation was itensified. In timberline, the highest losses of crop formation are observed from initial number of ovules to quantity of developed seeds (to 60 %). The changes at the timberline influence on mesophyll, resin canals, epidermis of needle cells. At the timberline the chloroplast thylakoid system is not neither to "light" nor to a "shadow" type. Chloroplast functional acitivity at the level of photosystem II half as much at the timberline. Maintenance of metabolism level at low energy photosynthesis potential is compensated by increasing of respiration at 30-40 % and increasing of mitochondira number in 1.6 times.