DIGITALNA ARHIVA ŠUMARSKOG LISTA
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| ŠUMARSKI LIST 13/2005 str. 105 <-- 105 --> PDF |
V. Ivančević: BIOLOGICAL AND TECHNICAL REGULATION OF THE SENJ TORRENT "TORRF.NTF." Šumarski list - SUPLEMF.NT (2005), 91-109 ly. At such a rate, the quantity of the eroded material is always lower than the quantity of the formed material. The geological substrate, the vegetation and other external impacts determine the development of varied soil types. Senjska Draga is dominated by shallow and skeletoidal brown sub-Mediterranean soils, while rendzinas, red soils, brown eutrophic soils, acid brown soils, humus - silicate soils and other soil types alternate sporadically in a mosaic-like pattern. Climate According to Köppen´s classification, Senjska Draga belongs to the continental variety of the Mediterranean climate (Cfsax"). According to Thörnthwait´s index, it belongs to the zone of humid climate. The mean annual temperature of 9.1 °C and the annual precipitation average of 1.700 mm is characterised by a pronounced autumn maximum and summer minimum. This area suffers sudden weather changes, particularly when large quantities of air mass are on the move. These changes are responsible for strong winds (bura/northcrly and y «go/southerly), which have a negative impact on the development of vegetation and soil. Vegetation According to the phytogeographic classification, the forest vegetation of Senjska Draga belongs to the sub-Mediterranean vegetational zone and the Mediterranean - montane vegetation belt of the Adriatic province of the Mediterranean region. To a lesser degree it also belongs to the Illyrian province of the North-American forest region. The first zone, containing forests and thickets of oriental and hop hornbeam of the alliance Ostryo-Carpinion orientalis Ht. in two altitudinal belts, extends from the sea to 700 m above the sea towards the hinterland (Pelccr, 1972). The first belt from 0-300 m is covered with forests of pubescent oak and oriental hornbeam (Querco-Carpinetum orientalis H-ić 1939) and degraded communities of ornamental grass and sage (Stipo-Salvietum officinalis H-ić). Ori ental hornbeam is only partially represented, while hop hornbeam extends as far as the sea. The second belt from 300-700 m is inhabited by forests of pubescent oak and hop hornbeam (Ostryo-Quercetum pubescentis Ht. 1938), mostly in the form of degraded thickets in varying stages of the secondary phytocoenosis Seslerio- Ostryetum. Within the forest of pubescent oak and hop hornbeam there are several subassociations and wasteland communities, including sedge and knapweed {Carici-Centauretum rupestris Ht.), savory and campanula {Satureio-Edraeaenthetum Ht.) and several extra-zonal communities. As a final degradation stage in the forest there are thickets of common juniper (./. communis) and prickly juniper (J. oxycedrus). The largest areas of Senjska Draga are covered with forests and degraded stages of the second belt. Apart from the zonal, there are also several extra-zonal communities. These include autochthonous forests of black pine with cotoneaster {Cotonaestro-Pinetum nigrae Ht. 1938), forests of sessile oak with woodrash (Luzulo-Quercetum petraeae I Hill. 1983 / Pass. 1963), forests of sessile oak with brooms (Luzulo-Quercetum petraeae genistetosum prov. Pelc.) and forests of beech with woodrushes (Luzulo-Fagetum Wrab.). The second vegetation zone towards the continental hinterland from 700 m upwards contains beech forests with autumn moor grass (Seslerio-Fagetum sylvaticae /Ht. 1950/ M. Wraber 1960) extending up to the sub- mountainous beech forests {Fagetum illyricum subalpinum Ht.). The elements of xerothermal sub-Mediterranean forests and mesophytic beech forests are represented in the prevailing beech forests with autumn moor grass. Apart from the mentioned forest communities and their degraded forms, there are also 22 artificially established cultures - enclosures of black pine covering 320 ha and distributed in a mosaic-like pattern across Senjska Draga. Not only do these cultures enclosures have a predominantly protective role, but they also play a key role in the successful regeneration of autochthonous vegetation (Figure 1). A HISTORICAL SURVEY OF FORESTS IN SENJSKA DRAGA From preserved forests to their disappearance According to research by Magdić (1877), at the turn of the 16lh and the 17th century the surroundings of Senj, including Senjska Draga, were covered with dense forests of oak and fir! (it was most probably black pine, not fir). In the early 17th century mention was made of the preserved forests of Senjska Draga in connection with the resettlement of the uskoci (rebel fighters against the invaders) from Senj into the interior of the country. Profits from the sale of these forests were to be used by Venice to cover the costs of their resettlement. Bishop De Dominis of Senj was to receive a commission as the middleman in this transaction. However, the violent death of Rabata, the military commander of Senj, and the opposition staged by the Viennese court undermined the realisation of this plan (Sever in ski, 1967). The forests of Senj must have disappeared in the first half of the 17th century, since a highly destructive torrent in 1647 inflicted enormous damage to the Town of Senj, destroying a part of the town walls and 50 houses within the town (Vi tezo vic, 1696). Clearly, the torrent caused such devastating damage because the forests in Senjska Draga had already completely disappeared. At that time, the Senj |