Effects of the light regime on natural regeneration of sessile oak ( quercus petraea matt . Liebl .) Forests in Fruska Gora national park, Serbia

Abstract

The paper presents the results of a study on the regime of light and regeneration in a pure sessile oak stand in 'Fruska Gora' National Park in Serbia. Pure sessile oak stands cover 3960.73 ha or 17.6% of the area. The study stand is ecologically classified as the forest of sessile oak with fescue (Festuco drymeiae - Quercetum petraeae Jank. 1974) on acid brown and illimerised soil over sandstone. The 96 year-old stand is even-aged and vegetative. It is located on east and west facing slopes at an altitude of 450 m, with the slope inclination of 32 degrees. The starting hypothesis of this paper was that light regime has significant effects on the success of sessile oak forest regeneration. Data collection was performed in early July 2008. The study of regeneration elements (seedling number, height and quality) was conducted at the end of the growing season at the seedling age of 3. Light conditions that arc most favorable for regeneration include the intensity of illuminance between 5000 Lx and 10000 Lx, i.e, 1 1,3% to 22.6% of full daylight. The number of seedlings and their spatial distribution on the regeneration plot are in these specific site and stand conditions affected by the light regime of the area, making light most decisive, but not the only factor affecting their spatial distribution.