Abstract
Plitvice Lakes National Park is situated in the inland mountain region of Croatia (about 60 km from the sea), between the high mountains of Mala Kapela to the southwest and Li~ka Plje{ivica to the southeast. This is a typical karstic area, which is particularly obvious from the orographic and hydrological characteristics of the terrain. The surface and underground watercourses are dependent on the geological structure, and they greatly influence the development the flora and vegetation. The relief, especially the great altitude range of 913 m, adds to the biodiversity of the flora and vegetation of the Park. The natural uniqueness of the area of Plitvice lakes National Park is recognised by the UN, and in 1979 UNESCO put the Park on the List of the World Cultural and Natural Heritage. The area of Park is mostly covered by forests (80 %) of different communities. The rest (except for the open waters) is overgrown by a number of different anthropogeneous vegetational types, just a small part belonging among natural moor and swamp habitats. Detailed surveys of vegetation in National Park Plitvice Lakes were made in the period 1984– 1990. In this interval, all the vegetation types within Park, as well as in the surrounding area outside of the old borders of Park (which have later been expanded) were investigated. In total, 366 phytosociological relevés were made then in the area of the Park. The data from those vegetation surveys could be taken as the degree zero for data concerning the mentioned vegetation types, since it was documented just in time, considering the stage of the vegetation succession at this moment. The vegetation of the grassland, moor and swamp habitats in the Park syntaxonomically belongs to 5 vegetation classes, 8 orders, 10 alliances, 19 associations, and 8 stands of the species Ligularia sibirica, Calamagrostis epigejos, Nardus stricta, Menyanthes trifoliata, Marchantia sp., Pinguicula vulgaris-Tofieldia calyculata, Equisetum hyemale and sphagnum bog. From the phytogeographical, ecological and floristic standpoint the investigated areas represent valuable ecosystems, containing a number of plant and animal species. Human influence on the originally forest habitats enabled the development of different grassland and other ecosystems. A large part of the investigated areas, particularly those grasslands within the Park, are in different stages of progressive vegetation succession. Some woody plants are invading these grasslands from the nearby forests. The length of the period during which a pasture is not mown or is abandoned determines the number of woody shrubs and their appearance, which in turn is re- Nat. Croat. Vol. 14, Suppl. 2, 2005 3 flected in the appearance of the grasslands, the floristic composition, number of species and their distribution over the grassland, leading to substantial habitat changes. From the natural standpoint, the progressive vegetation succession is a positive process, leading to the original, natural, virgin forests which covered the area before the human influence. But from the standpoint of biodiversity, such process is negative, causing a decrease in flora and vegetation diversity, as well as a decline in total biodiversity. This paper presents a short review of the state of the grassland, moor and swamp habitats and their protection. Special attention is given to the stage of the vegetation in Park at the time of the surveys (1984–1999). The diversity of the habitats and the vegetation, and the richness of the plant species are pointed out. In addition, measures are proposed to preserve and protect the diversity and the characteristics of the grassland, moor and swamp vegetation of the Park, and the richness of its flora. In addition to the vegetation review of the Park habitats, the paper contains a description of some of the characteristic and rare plant species of this area.
Keywords
vegetation, grasslands, moors, swamps, progressive vegetation succession, biodi- versity conservation, National Park Plitvice Lakes, Croatia PREDGOVOR Na osobitosti krajolika i ljepotu Plitvi~kih jezera skrenuli su pozornost znanstvenici-prirodoslovci pred vi{e od 100 godina, ali i niz znanstvenika i prirodoslovaca u kasnijem razdoblju. Svi oni nagla{avali su izuzetnost i ljepotu jezera, osobitosti njihovog postanka, te osnovne i temeljne vrijednosti prirodnog fenomena sedre i sedrotvoraca. Zajedni~ka `elja svih bila je za{tita i o~uvanje ~itavog prostora oko jezera kao izuzetnog spomenika prirode. Stalno isticanje fenomena postanka i stvaranja sedre, i ostalih osobitosti Plitvi~kih jezera, njihove ljepote, ljepote krajolika koji ih okru`uje, nakon nekoliko ranijih poku{aja rezultiralo je 1949. godine progla{enjem Nacionalnim parkom. To je bio prvi Nacionalni park u Hrvatskoj, nazvan »Nacionalni park Plitvi~ka jezera« kao predio naro~ite prirodne ljepote. Godine 1997. tj. 48. godina kasnije ozakonjeno je i pro{irenje granica Parka na povr{inu od 294,82 km2. Izuzetnu prirodnu neponovljivost prostora Nacionalnog parka Plitvi~ka jezera utvr|uje i Organizacija Ujedinjenih naroda, njezin odio UNESCO, koji 1979. godine stavlja prostor Parka na Listu Svjetske kulturne i prirodne ba{tine. Od vremena za{tite i progla{enja prostora oko jezera Nacionalnim parkom, na njegovom su prostoru vr{ena intenzivna istra`ivanja, prvenstveno osnovnog fenomena nastanka jezera, njihovog odr`anja i sveukupnih `ivotnih prilika u i oko jezera. Nadalje, vr{ena su i ostala istra`ivanja u`eg i {ireg prostora oko osnovnog fenomena jezera, prvenstveno geolo{ka, pedolo{ka, klimatolo{ka, te `ivi svijet (biljni i `ivotinjski) prostora Parka. Istra`ivanja biljnog svijeta bila su do progla{enja tog prostora Like Nacionalnim parkom vrlo oskudna. U 19. stolje}u ograni~ena su na usputni prolaz kroz taj dio