Ecophysiological Parameters as a Possible Tool for the Assessment of Natural and Artifical Regeneration in Pedunculate Oak in Lowland Parts of Slovenia

2000

S. 201-213

9 Abb., 1 Tab., 17 Lit. Ang.

Unselbständiges Werk

200085175

Glasnik za Sumske Pokuse 2000 ; 37, S. 201-213
; 37

In the last decade there has been a noticeable decline and physiologically weakening of the pedunculate oak (Quercus robur L.) in lowland parts of Slovenia due to a drier climate, unfavourable precipitation patterns, and human influence through changes in watercourses and the water table. Regeneration and future management of this tree species is therefore under question. In order to define a critical groundwater table and light conditions which would permit sucessful regeneration, an experiment was carried out in two bigger pedunculate oak forest complexes (Murska Suma and Krakovo Forest), differing by the degree of the level of decline and the physiological weakness of the adult trees. Wihin each forest complex two locations with permanent high and low groundwater tables were chosen. On each location pedunculate oak seedlings (2 + 2) were planted in three different light regimes (without canopy cover, under minimal, medium and maximal tree canopy). In every aspect (spring, summer, autumn), measurements of pre-dawn and midday water potential and photosynthetic activity on natural and planted seedlings were performed daily. Groundwater table measurements and qualitative analysis were carried out through the whole measuring period. The experiment confirmed significant differences between physiological indicators within each forest complex as well as between both Murska Suma and Krakovo Forest. The critical groundwater level in connection with the light conditions for efficient regeneration in those forest complexes was also difined.