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ŠUMARSKI LIST 7-8/2023 str. 87     <-- 87 -->        PDF

declining to 16−18 °C in the growing season. The average annual precipitation in the Deliblato Sands area is 664.15 mm. Its climate is primarily governed by the southeasterly wind Košava, which is cold and dry during winter, early spring and late autumn. According to Kadović et al. (2004) and Ali Bohajar (2015), in this region, the average temperature increases by 0.50−0.75 °C every 100 years, while total annual precipitation exhibits a slight (5%) positive trend. Changes in measured parameters clearly indicate the present trend of climate change, and global warming which can directly or indirectly affects biodiversity.
Deliblato Sands vegetation formation – Formiranje vegetacije Deliblatske pješčare
In all sandy areas in Serbia, successional stages of vegetation took a long time to develop. The process commenced with the germination of seeds blown by the wind from both surrounding and more remote areas. These pioneering stages of vegetation mainly comprised therophytic plant species, with low coverage and diversity. This initial vegetation is of key importance for the binding of sand masses and the development of soil on sand because it creates favorable conditions for the growth of perennial plants that form the next stages of vegetation on sand. The appearance of steppes, forest-steppes and forests on sands was accompanied by the expansion of the daily needs of the surrounding population. Due to the excessive exploitation of plant cover, the sand was released again, and was blown into the air and moved by wind. Efforts to mitigate these adverse outcomes were mostly unsuccessful. Under the threat of sandstorms, “flying sand” buried the crops and dried up the orchards and vineyards, the local population felt defeated and eventually moved away (Pančić, 1863). Unbound “flying sand” lasted until the middle of the 20th century (Figure 2).
Today, on all natural sand accumulations in Serbia—almost no free sand remains (Figure 3). The Deliblato Sands are covered by set of phytocenoses developed in different micro-ecosystems—from sandy, steppe, pasture, shrub, forest and meadow, to numerous anthropogenic stands—that form a mosaic. Sand vegetation is present only in fragments, mainly in the central part of the Reserve. The largest areas under steppe vegetation are located in the north-western part and in narrow belts or fragments within the central and peripheral parts, together with the remnants of oak and linden forests (Querco-Tilietum tomentosae Stjepanović-Veseličić 1953.) or individual trees of these species (Tilia tometosa Moench, Quercus robur L. or Quercus pubescens