Synecology of Silver Fir (Abies alba Mill.) Communities in Northern Croatia and Floristic Parameters Important for Management of Beech Fir Forests

1991

S. 303-316

27 Lit. Ang.

Unselbständiges Werk

200091668

The doctoral dissertation "Synecology of Silver Fir" (Abies alba Mill.) Communities in Northern Croatia and Floristic Parameters Important for Management of Beech/Fir Forests" investigated and determined the floristic composition, range and microclimatic characteristics of photocoenosis of Beech/Fir forests, state of health of the Beech, florstic parameters, stand conditions and the most favourable way of management. The results of the investigation show that the range off the Fir and Beech communities in northern Croatia is disjuncted and is located at Macelj Gora, Trakoscan, Strahinjcica, Ravna Gora, Ivancia, Medvednica and Papuk. The range of phytocoenoses covers 14.702 ha, while it is also found separately in other comunities, in which it is not a characteristic species, covering another area of 2.835 ha. The range shows a tendency to reduce at Medvednica, but to in increase at Macelj and Papuk. The health state of the Fir has drastically deteriorated, and is becoming worse. In 1986 31% of the volume of wood belonged to one of 5 categories of crown damage due to the falling of needles, while in 1988 this figure was increased to 72%. By analyses of the floristic composition of vegetation at 128 phytocoenological surfaces, 20 x 20 m, and 9 surfaces, 60 x 60 m two associations were determined, of which one had two sub-associations, as follows: ass. Abieti-Fagetum pannonicum Raus 1969; subass. typicum, nova; subass. cardaminetosum trifolae, nova; ass. Blechno-Abietetum Horvat 1950. Typicum and cardaminetosum trifoliae are new sub-associations, established and phytocoenologically recorded for the first time in this investigation. Geographical position and spatial arrangement of the ranges of forest phytocoenoses is shown on the map of northern Croatia on a scale 1:500.000 and on the five maps showing management units on a scale 1:25.000. Microclimatic investigations determined essential differences in microclimatic characteristics according to particular mountain massifs and forest associations. In identical general climatic conditions the values of microclimatic elements, primarily the air temperatures on Macelj Gora, were considerably higher than on other mountains, which leads to the conclusion of the higher effectiveness of daily insolation. A characteristic microclimatic trait in the Blechno-Abietetum association is an increase in temperature values from the lowest to higher measuring gradients (up to 2 m), while this is not characteristic of the association Abieti-Fagetum pannonicum. In the Abieti-Fagetum association the temperatures in the crowns of Fir trees are regularly higher than at heights of up to 2 m, while in the Blechno-Abietetum they are different compared to other heights, depending on the aspects. Floristic parameters important for the management of Beech/Fir forests are characteristic species of associations and ........