BIODIVERSITY OF MACROPHYTE VEGETATION FROM LAKE PRESPA, LAKE OHRID AND LAKE SKADAR

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1 BIODIVERSITY OF MACROPHYTE VEGETATION FROM LAKE PRESPA, LAKE OHRID AND LAKE SKADAR M. Talevska 1, D. Petrovic 2, D. Milosevic 2, T. Talevski 1, D. Maric 2 and A. Talevska 3 1 Hidrobiological Institute Ohrid, R. Macedonia 2 Department of Biology, Faculty of Science and Mathematics, University of Montenegro, Podgorica. Montenegro 3 Faculty of Science and Mathematics, Institute for biology, University St. Kiril and Metodij Skopje, R. Macedonia, Correspondence to: Marina Talevska mtalevska2000@yahoo.com ABSTRACT Lake Prespa, Lake Ohrid and Lake Skadar are the biggest lakes in the Balkan Peninsula. By reason of continuous existence and relatively stable ecological conditions millions years those lakes have a unique collection of flora and fauna. In this paper is presented biodiversity of macrophyte vegetation from Lake Prespa, Lake Ohrid and Lake Skadar. In those three lakes macrophyte vegetation is distributed in zones (belts). The biodiversity of macrophytes is different in those lakes and it is in direct dependence of different altitudes, lakes surfaces and lakes depths. Keyword: biodiversity, Lake Ohrid, Lake Prespa, Lake Skadar, macrophyte vegetation Introduction The macrophyte vegetation is found thought the littoral zones of lakes and have significant role in the cycling of materials in them. Namely, it is important producer of oxygen, and supply the lake bottom and surrounding waters with different organic and mineral materials during the vegetative period, especially in the period of decay. The macrophytic plants serve as natural mechanical and biological filters as they clean the lake water of various organic and inorganic pollutants. They also slow down erosion of the rich topsoil, by anchoring it with the roots, and in same times they produce large amount of plant detritus. The macrophytes provide habitat, shelter and food for a large number of invertebrates and vertebrates organisms from the littoral zone. Materials and methods This paper is result of long-term researches of macrophyte vegetation from Lake Prespa, Lake Ohrid and Lake Skadar. The researches are performed by the Department of Hydrobotany from Hydrobiological Institute-Ohrid, R.Macedonia and Department of Biology, Faculty of Science and Mathematics, University of Montenegro, Podgorica, Montenegro. The materials of macrophyte vegetation were collected from Lake Prespa, Lake Ohrid and Lake Skadar by standard lymnological methods. Collected materials of macrophyte vegetation were determinate in laboratories of the researchers. Investigated area Lake Prespa is second big lake in Dessaret lake group, and fulfils the deepest part of Prespa valley. Lake lies at an altitude of 853m, has surface area of 274 km 2, maximal length about 28 km, and maximal width about 17 km. It is 54 m deep, and it has a small transparency (from 2m to 6m). The lake gets it waters from underground springs and also from the rivers: Istocka, Golema, Pretorska and the River Brajcinska in the Macedonian part of the watershed and river Stara in the Greek part. Lake Ohrid is the largest and deepest lake in the Dassaret lake group. It fulfils the deepest part of Ohrid valley. At a sea level of m Lake Ohrid has a surface area of km 2, maximal length of 30.5 km, and maximal width of 15 km. Lake has maximal depth of m, and a great transparency of water (21 meters). Lake Ohrid supply with water from surface springs, sublacustric springs and surface tributaries (rivers Koselska, Velgoska, Sateska and Cherava). From the Lake outflow river Crn Drim. Lake Skadar is the largest lake at Balkan Peninsula. Lake is located in Zeta Skadar valley and is surrounded by mountains and 7 km far from Adriatic Sea. Depending of 931

2 level of water, surface area of Lake varies from 370 to 530 km 2. It is 44 km long and 14 km wide, and deep about 8 meters, with transparency of the water from 2 to 3 meters in the summer and up to 5 meters in the winter. The lake receives water from surface water courses and from underground sublacustrine springs ("eyes"). In the Lake influx rivers Moraca, Crnojevica, Karatuna and Orahovsica. The main outflow from the lake is the River Bojana. Results and discussion In the littoral region of Lake Prespa are distributed different populations of macrophyte vegetation which always presents vertical zonal reparation. Dominant emerged plant species in Lake Prespa is reed Phragmites australis (Cav.) Trin. ex Steud. which form a natural discontinuous belt. The other emerged plants (Typha latifolia L., Typha angustifolia L., and Shoenoplectus lacustris (L.) Palla) are present rare. Floating plants are very rare (it is present Polygonum ampibium L.). From submerged macrophytes which are present in Lake dominant are the representatives from genus Potamogeton: Potamogeton perfoliatus L., Potamogeton pectinatus L., Potamogeton lucens L. and Potamogeton pussilus L. Lesser present are: Zannichellia palustris L., Myriophillum spicatum L., Ceratophyllum demersum L., Ceratophyllum submersum L., Vallisneria spiralis L., Najas major All., Najas minor All., and athers (Tab.1.). In Lake Prespa, the macrophyte vegetation shows the relatively great species diversity in different parts of littoral (7). Great number of macrophyte species is evidenced in North and North Western coastline of Lake, respectively in region where river Golema falls into the Lake. In other parts of littoral region the number of macrophyte species is lower. Biodiversity of macrophyte vegetation from Lake Prespa, Lake Ohrid and Lake Skadar TABLE 1 Species Lake Prespa Lake Ohrid Lake Skadar 1. Phragmites australis (Cav.) Trin. ex Steud Typha latifolia L Typha angustifilia L Butomus umbellatus L Butomus umbellatus L. ssp.scutarensis Lak Sagitaria sagittifolia L Cyperus longus L Sparganum ramosum Huds Sparganum erectum L Heleocharis pallustris R.Br. (Scipus paluster L.) Shoenoplectus lacustris (L.) Palla (Scipus lacustris L.) Roripa silvestris (L.) Pess Alisma plantago- aquatica L Mentha aquatica L Caltha palustris L Polygonum amphibium L Polygonum amphibium-erectum L Nymphaea alba L Nuphar lutea (L.) Smith Nymphoides peltata (S.G.Gmel) O.Ktze Trapa natans L Trapa longicarpa M.Jank. ssp. scutarensis M.Jank Lemna minor L Lemna major L Lemna trisulca L Spirodela polyrrhiza Schl Hydrocharis morsus ranae L Potamogeton perfoliatus L

3 29. Potamogeton pectinatus L Potamogeton lucens L Potamogeton crispus L Potamogeton acutifolius Link Potamogeton pussilus L Potamogeton natans L Zannichellia palustris L Myriophyllum spicatum L Myriophyllum verticillatum L Ceratophyllum demersum L Ceratophyllum submersum L Vallisneria spiralis L Elodea canadensis Rich.& Michx Najas major All Najas minor All Utricularia neglecta Lehm Rannunculus divaracatus Schr Ranunculus circinatus Sibth Ranunculus repens L Chara tomentosa L. (Chara ceratophylla Wallr.) Chara imperfecta A.Br Chara aspera (Deth.) Willd Chara globularis Thill. (Chara fragilis Desv.) Chara ohridana (Kostic) Krause Chara denudata A.Br Chara vulgaris L. (Chara foetida A. Braun) Chara kokeilli A.Br Chara rudis A.Br Chara tenuispina A.Br Chara aspera (Deth.) Willd Nitella opaca (Bruz.) Ag Nitella gracilis (Smith.) Ag Nitella capillaris Gr.et Bull Webst Nitellopsis obtusa (Desv.) J. Groves Tolypella polifera (Ziz.) v. Leonhardi + In Lake Ohrid, where the bottom of the littoral region gradually decreases in depth, the macrophyte vegetation is distributed in belts: of Cladophora, of Phragmites, of Potamogeton, and of Chara (6, 8, 9, 10, 11). Dominant emerged plant species in Lake Ohrid is reed Phragmites australis which form a natural discontinuous belt. The other emerged plants (Typha latifolia L., Typha angustifolia,l., Shoenoplectus lacustris (L.) Palla) are present in the belt of reed and in particular regions form almost pure associations. Between the reed belt and the land, in some places are present the floating leaf plants Nuphar lutea (L.) Smith. and Polygonum ampibium L. Submerged macrophytes present in Lake are: Potamogeton perfoliatus L. (which is dominant representative), Potamogeton lucens L., Potamogeton crispus L.,Potamogeton pectinatus L., Potamogeton acutifolius Link., Myriophillum spicatum L., Myriophillum verticilatum L., Ceratophyllum demersum L., Ceratophyllum submersum L., Vallisneria spiralis L., Zannichellia palustris L., Elodea canadensis Rich.& Michx., Najas major All., and Najas minor All. Also, there are present more species from Charophyta (12): Chara tomentosa L. (which is dominant representative), Chara imperfecta A.Br., Chara aspera (Deth.) Willd., Chara globularis Thill., Chara ohridana (Kostic) Krause., Chara denudata A.Br., Nitella opaca (Bruz.) Ag. and other. In Lake Ohrid, the macrophyte vegetation shows the 933

4 relatively great diversity of species in different parts of littoral. Great number of macrophyte species is evidenced in the North and in the South coastline of Lake, and in the regions where tributaries fall into Lake Ohrid, especially in locality Grasnica. Lower number of macrophyte species is evidenced along North-East and East coastline of Lake (9, 14). Macrophyte vegetation in Lake Skadar is characterized by presence emergent, floating and submerged macrophytes, and it is distributed in zones (belts). In zone of emerged plants dominant plant species are: Phragmites australis (Cav.) Trin. ex Steud.(Phragmites communis Trin.), Scirpus lacuster (L.) Palla (2, 5, 3, 4) and Typha angustipholia L. The other emerged plants are: Butomus umbellatus L. ssp.scutarensis Lak., Sparganum erectum L., Heleocharis pallustris (L.) R. et Sch., Cyperus longus L., Roripa silvestris (L.) Pess. and the others. Floating macrophytes which are dominant in Lake Skadar are: Nymphaea alba L., Nuphar lutea (L.) Smith., Trapa natans L., ( 2, 5, 3), Nymphoides peltata (S.G.Gmel) O.Ktze., Polygonum amphibium-erectum L., Potamogeton natans L., Lemna minor L., Lemna major L., Lemna trisulca L., and others. It shall to mention that in this lake is present aquatic plant Trapa longicarpa M.Jank. ssp. scutarensis M.Jank (water chestnut) which is endemic-relict specialized Skadar subspecies. Submerged macrophytes which are dominant in Lake are: Potamogeton perfoliatus L., Potamogeton lucens L., Potamogeton crispus L., Potamogeton pectinatus L., Potamogeton pussilus L., Myriophillum spicatum L., Myriophillum verticilatum L., Ceratophyllum demersum L., Ceratophyllum submersum L., Vallisneria spiralis L., Najas major All., and Najas minor All. Also, there are present Chara vulgaris L., Chara fragilis Desv. (which are dominant representatives from Charophyta), Chara kokeilli A.Br., Chara rudis A.Br., Chara tenuispina A.Br., Chara aspera (Deth.) Willd., Nitella opaca (Bruz.) Ag., Nitella gracilis (Smith.) Ag., Nitella capillaris Gr.et Bull Webst., Nitellopsis obtusa (Desv.) J. Groves., Tolypella polifera (Ziz.) v. Leonhardi and other species from Charophyta ( 1). Among particular regions of Lake Skadar shore are differences in diversity of macrophyte vegetation. Namely, along the eastern lake shore has evidenced great diversity of species. In the southern and southwestern shorelines macrophyte vegetation is very rare, and that which is found is generally limited to the area at the mouth of the Crmnica River at Virpazar, Godinje Bay and other small bays. The macrophyte vegetation from Lake Prespa, Lake Ohrid and Lake Skadar provide habitat, shelter and food for a large number of fishes. Also, its represent the spawning ground for some cyprinids fishes, and have a large role in protecting of fishes from their predators. Anthropogenic influence on biodiversity of macrophyte vegetation is very expressed in the last half of 20 century. As a result of such undesirable impacts, new macrophyte associations started to occur (especially the submerged plants), and the floating leaf plants are rare. The impact of negative human activities on macrophyte vegetation may result in reduction of their spawning grounds (13, 14), respectively changes in the composition of cyprinid fishes (15). Conclusions From the performed long-term researches of macrophyte vegetation from Lake Prespa, Lake Ohrid and Lake Skadar the obtained results may be summed up in following conclusions: In those three lakes macrophyte vegetation is distributed in belts (zones) which are continuous or discontinuous. From all evidenced macrophytes with greater number are present submerged macrophytes, then follow emerged, and the lower are present floating leaf plants. The biodiversity of macrophytes is different in the three lakes and its are result of different ecological conditions in their littoral zones: configuration of the lake bottom, type of soil, the water level, temperature, light, level of nutrients etc., as well as from different lakes altitudes, lakes surfaces and lakes depths. The anthropogenic pressure in respective parts of the lakes provokes changes in the composition of the bottom and the quality of the water. As a result of such undesirable impacts, new macrophyte associations started to occur, which may result in change of the spawning grounds of fishes, respectively in changes of their composition. With respect to significant role of macrophyte vegetation in the littoral zone, in the following period it is necessary to undertake certain measures for its permanent monitoring and its protection of the negative anthropogenic impact. REFERENCES 934

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