DIGITALNA ARHIVA ŠUMARSKOG LISTA
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| ŠUMARSKI LIST 9-10/1997 str. 68 <-- 68 --> PDF |
A. Tomašević: POVIJEST POŠUMLJAVANJA NA OTOKU VISU Šumarski list br. 9-10, CXXI (1997). 5 15-526 The parent rock of Vis was created in the geological periods of Jurassic, Cretateous, Tertiary and Quaternary. Jurassic is little presented by the basic eruptive rocks, diabase and spilits found in the vicinity of Komiža, found together with the Triassic marls, gypsum and erruptive tufa. Cretaceous sediments are presented by the carbonate layers of the upper and lower Cretaceous and they build the major part of the island (95%). The soils may be divided in those found in the fields, dales and bays, and those on the karst hillslopes. The soils are generally poor for any forest production. They are mainly skeletal and skeletioid, over strongly inclined terrains. There are very many anthropogenetic soils that were deserted by the end of the 19th and 20th centuries. These are mainly terraces where people grew grape wine, later destroyed by wine pest and also for social and political reasons. Uninteresting to agriculture, these abandoned terraces could be planted with forest trees, to bring green vegetation to the area, with all benefits forests can provide. The climate is Adriatic, typically Mediterranean. The period of maximum rainfall is in the autumn and winter, with an additional maximum in the springtime. The minimum rainfall is in the summers, which is mostly the time of summer droughts. The characteristic vegetation of the island are evergreen forests with its devastated and degraded forms of the Quercetalia ilicis order. Guided by the to date knowledge of the composition and structure of the evergreen forest vegetation of our coastland, Trinajstić (1985) divided the Mediterranean region phytogeographically in the following way: I. The Mediterranean-littoral vegetation belt 1 .Stenomediterranean vegetation zone of the wild olive forests (Olea-Ceratoniaon) 2.Eumediterranean vegetation zone of the evergreen oak (Quercion ilicis p.p.) //. The Mediterranean-montane vegetation belt 1 .Hemimediterranean vegetation zone of mixed evergreen oak and black hornbeam forests (Quercion ilicis p.p.). Upon my suggestion, the Split forest management laid in 1995 in Zaravničić a 60x60m large experimental plot in the form of Latin square. We then planted 144 seedlings of Cypress and 144 of Atlantic Cedar, and the same number of each plant so that they were supplied with a water reserve. The experiment was done to see to what degree would it help the plants in overcoming the summer droughts. Besides the Aleppo Pine, Common Cypress, and the Atlantic Cedar, it would be useful to introduce other cedars, Greek Fir, Arizona Cypress, Brucian Pine, Maritime Pine, and other species that are supposed to thrive on the island. We should not forget to mention the wild olive (Olea europea var oleaster Fiori), as it is the species that can very well grow in karst conditions. Wrongly considered only an agricultural species, olive deserves more consideration in karst afforestation, simply because it performs all the functions of a useful plant that has survived over many hundreds of years. Throughout its history, there had been almost never any afforestation on the island of Vis. The first tree planting was done near the town of Vis, by the teachers and professors of the civil and primary schools. From 1955 until 1960, in some parts of the island students and professors of the Secondary forestry school for karst planted Aleppo Pines, a few Cypresses, and the acorn of the evergreen oak. The Stonac Bay was afforested in 1955 by planting one-year-old seedlings of the Aleppo Pine, bare-rooted, 5000/ha. Table 9 contains data on the structure of this culture. Today, age 41, wood mass is 101.96 mVha, annual mean increment 1.49 m\ the tallest tree 15 m, the shortest 7 m, with the mean tree diameter 21.8 cm. There are 465 trees on one hectare, and the basal area is 18.99 m\ According to the observation of the organizer of these afforestation operations Mr. Oskar Piškorić, B.Sc. in forestry engineering, who started work as a young engineer, the work has been successful. It is demonstrated by the present condition of the Aleppo Pine cultures planted between 1955 and 1960. |