Referat The Danube Delta

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THE DANUBE DELTA GEOGRAPHICAL LOCATION Lies on the coast of the Black Sea in the eastern part of the country in Tulcea County, and encompasses the area between the branch rivers Chilia, Sulina and Sfintu Gheorghe, the former creating the boundary between Romania and the Ukrainian SSR. The site also includes the Razelm-Sinoie complex of lakes Razelm, Sinoie, Zmeica and Golovita to the immediate south of the delta. 44° 25 -45° 28 N, 29° 42 -28° 45 E DATE AND HISTORY OF ESTABLISHMENT In 1938 the Council of Ministers passed Decision No 645 declaring Letea Forest as a nature reserve. In 1961 it passed Decision No 891 declaring Rosca-Buhaiova (14,600ha), St George-Perisor -Zatoane (16,400ha), Periteasca-Gura Portitei (3,900ha) and Popina Island (98ha) as nature reserves. In 1971 the Management of Forestry declared the Caraorman Forest (840ha) and Erenciuc Forest (41ha). In 1975 the Council of Ministers passed the Decision No. 524 extending the Danube Delta protected areas to cover 41,500ha. In 1979, an area of 18,145ha combining Rosca-Buhaiova Reserve and Letea Forest was internationally designated as Rosca-Letea Biosphere Reserve. An area of 500,000ha including all previous designations was declared a biosphere reserve under National Decree No. 983 with supporting Articles 5, and 6 on 27 August 1990. Further legislation is under preparation. This area was further enlarged in early 1991 to cover 547,000ha and was also declared a national biosphere reserve. The latest legislation gives patrimony of the biosphere reserve to the Delta Authority. Decree 264/91 passed on 12 April 1991 places all institute, agency and inspectorate staff under the administration of the biosphere reserve. The environment agency for Tulcea Judet is also subordinate. All public domain and aquatic and natural resources generated are the ownership of the biosphere reserve authority. Further legislation will significantly strengthen the administration of the site. Danube Delta was designated a Wetland of International Importance under the Ramsar Convention in 1991, inscribed on the World Heritage List in 1991 and internationally recognised as a Biosphere Reserve under UNESCO s Man and the Biosphere Programme in 1992. AREA 679,222ha, including 103,000ha marine. The entire delta region comprises 799,000ha of which 679,000ha are in Romania and 120,000ha in the Ukrainian SSR. The Razelm-Sinoie lagoon complex adds a further 88,000ha. The exact boundary of the site put forward for nomination has been altered to exclude less natural areas such as the Pardina polder and the fish ponds in the south-west ALTITUDE Sea-level to 15m PHYSICAL FEATURES The origin of the Delta can be traced to the Ice Age. The present geomorphological form has evolved in historical times. The northern part of the Delta is slowly sinking, resulting in measurable water flow increase in the Chilia arm of the Danube. Only 9% of the area is permanently above water (EEN, 1990). The Delta is extensive in European terms (some 12 times the size of Cota Donana Reserve on the Guadalquivir Delta, Spain) with numerous freshwater lakes interconnected by narrow channels with huge expanses of aquatic vegetation. The Razelm-Sinoie complex to the south consists of several large brackish lagoons separated from the sea by a sandbar (Grimmett and Jones, 1989). Every year thousands of tons of alluvial deposits are carried into the Delta by the Danube resulting in a constant reshaping of the river banks and sandbars. The overall basic hydrological and ecological systems of the Delta, although strongly degraded, are considered intact. Rosca-Buhaiova-Hrecisca Nature Reserve (part of Rosca-Letea Biosphere Reserve) is considered almost unaltered by man due to the shallow water level making access almost impossible. Perisor-Zatoane-Sacalin Nature Reserve is a mosaic of lakes and ponds and reedbeds with parallel strips of sand dunes ( grinduri ). Sacalin Island is made up of alluvial deposits with sand dunes and Tamarix. The Delta has been classified into 12 habitat types as follows: aquatic habitats - lakes (0.80m - 2.50m depth) covered with flooded reedbeds; plaur - flooded islets; flooded reeds and willows; riverine forest of willows and poplars; cane-fields; sandy and muddy beaches; wet meadows; dry meadows (arid); human settlements; sandy and rocky areas; steep banks; and forests on high ground (Ciochia, n.d.). CLIMATE The prevailing continental climate, with only 450mm of annual rainfall, is temporarily influenced by proximity to the sea and the humidity rising from countless inland lakes and small waterways (Anon., 1990). VEGETATION This is the largest continuous marshland in Europe which includes the greatest stretch of reedbeds probably in the world. The marsh vegetation is dominated by reeds Phragmites australis which form floating or fixed islands of decaying vegetation ( plaur ) with some Typha angustifolia and Scirpus sp. Reeds cover some 1,700 sq. km and plaur 1,000 sq. km, whilst the total area not included is only 148 sq. km (Ciochia, n.d.). There are also water lilies Nymphaea alba and Nuphar luteus and Stratiodes alloides. The higher ground supports stands of Salix, Populus, Alnus and Quercus. Sandy areas are covered with feather grass Stipa sp. and other steppe species. Forest elements are best observed in Letea Forest, occurring in a series of bands along dunes up to 250m long and 10m wide, where trees reach 35m in height. The species present are Quercus robur, Q. pedunculiflora, Populus alba, P.nigra, Fraxinus ornus, F. angustifolia, F. palisae, Pyrus pyraster, Tilia tomentosa, Ulmus sp., and the occasional Alnus glutinosa. Among the shrubs are Crataegus monogyna, Euonimus europea, Cornus mas, C. sanguinea, Rhamnus frangula, R. catharctica, Viburnum opulus, Berberis vulgaris, Hippophae rhamnoides, Tamarix spp. and occasional Corylus avellana. The distinctive feature of the forest is the abundance of climbing plants including Periploca graeca, Clematis vitalba, Vitis sylvestris and Humulus lupulus. In spring, the ground is carpeted with Convallaria majalis. Particularly rare and threatened plants include Convolvulus persica, Ephedra distachya, Merendera sobolifera, Plantago coronopus and Petunia parviflora . FAUNA Over 300 species of bird have been recorded, of which over 176 species breed (Radu, 1979), the most important being: cormorant Phalacrocorax carbo sinensis (3,000 pairs), pygmy cormorant P. pygmeus (K) (2,500 pairs comprising 61% of the world s population), white pelican Pelecanus onocrotalus (2,500 pairs comprising 50% of the Palaearctic breeding population), Dalmatian pelican P. crispus (E) (estimated at 150 pairs, perhaps now only 25-40 pairs, on the floating islands on lake Hrecisca, which represents 5% of the world population), night heron Nycticorax nycticorax (2,100 pairs), squacco heron Ardeola ralloides (2,150 pairs), great white heron Egretta alba (700 pairs), little egret E. garzetta (1,400 pairs), purple heron Ardea purpurea (1,250 pairs), glossy ibis Plegadis falcinellus (1,500 pairs), white stork Ciconia ciconia (many), mute swan Cygnus olor (500 pairs), white-tailed eagle Haliaeetus albicilla (V) (8 pairs), marsh harrier Circus aeruginous (300+ pairs), osprey Pandion haliaetus (3 pairs), Saker falcon Falco cherrug (1-2 pairs), red-footed falcon F. vespertinus (150 pairs), Sandwich tern Sterna sandvicensis (1,700 pairs), common tern S. hirundo (20,000+ pairs), whiskered tern Chlidonias hybridus (20,000+), and black tern C. niger (10,000-20,000 pairs). White-headed duck Oxyura leucocephala possibly still breeds. Slender-billed curlew Numenius tenuirostris (K) has occurred on passage (28 in 1971 and one or two in 1989). The Delta holds huge numbers of Anatidae in the winter with counts of 500,000 white-fronted goose Anser albifrons (but only 64,000-77,500 in 1982), up to 500 lesser white-fronted goose A. erythropus, 45,000 red-breasted goose Branta ruficollis (a globally threatened species with almost 95% of the world wintering population present here), 150,000 teal Anas crecca, 200,000 mallard A. platyrhynchos, 14,000 pintail A. acuta, 40,000 shovelor A. clypeata, 32,400 red-crested pochard Netta rufina, 970,000 pochard A. ferina, 13,000 ferruginous duck A. nyroca, and 1,500 red-breasted merganser Mergus albellus. In winter there is a concentration of some 30-40 Haliaeetus albicilla (R) (Grimmett and Jones, 1989; Green, 1990 ). The Delta is very important for fish with 45 fresh water species present including threatened representatives of the Acipensenidae (Anon., 1990). Otter Lutra lutra, stoat Mustela erminea, and European mink Mustela lutreola (E), as well as wild cat Felis sylvestris are to be found on the floating islands (Anon., 1990). It appears that little work has been done on mammals since 1970 largely as a result of lack of funding, but the mink population, although its size is unknown, is apparently significant in European terms. The forest areas contain several rare reptiles, including Vipera ursini, Elaphe longissiuma, and Eremias arguta deserti (IUCN, 1986). CULTURAL HERITAGE The very long history of trading along the Danube is evident from remains of Greek and Roman settlements (including a lighthouse). Villages surrounding the Delta show a Turkish influence. LOCAL HUMAN POPULATION Estimated at between 12,000 and 16,000 (most of Ukrainian orthodox Lipki descent), depending on the definition of the area covered and residence status (EEN, 1990; IUCN-EEP, 1991). The lower figure is considered to be 50% less than 50 years ago (Pons and Pons-Ghitulescu, 1990). The population is distributed along the three main waterways, Chilia, Sulina and Sfintu Gheorghe, the main source of drinking water. Cases of cholera have been reported (EEN, 1990), the latest in August 1990 when 66 cases were diagnosed in the Tulcea region (Anon., 1990a). Most of the younger generation has left the Delta and old fishing villages of reed huts have been replaced by concrete structures, although individual fishing huts are retained. Some villages (e.g. Gorgova) have no electricity. Social problems are exacerbated by low incomes due to set prices for fish (500 lei per 1,000 kg of fish; 1989 figures). Conditions for the workers on state farms (on the newly-created polders) are reported to be extremely bad (attempts to introduce eco-farming in the near future) they lack basic infrastructures and the work is unpopular. It is reported that the state farms were used as prison camps . Some constructions are inappropriate to the region such as the blocks of flats and large commercial complex at Sfintu Gheorghe which remain empty . The local population has been involved in small-scale, low-intensity use of natural resources supplemented by outside interests, such as fishing (10,000 boats are registered, cattle grazing and beekeeping, thought on the whole to be integrated to preservation of natural heritage. The centre of commercial activity in the Delta is the freeport of Sulina. In the late 1980s the town underwent rapid expansion with 500 new dwellings being built, an hotel and a shipping centre to handle 3,500 ships annually (Anon., 1987). Other urban developments have taken place at Chilia Veche, Sfintu Gheorghe, 1 Mai, Unirea and Independenta (Anon., 1987). VISITORS AND VISITOR FACILITIES Under the previous regime parts of the Delta were heavily used for tourism with up to 100,000 visitors annually, mostly concentrated at two hotels along the Sulina channel, although many camp along major channels in the summer Permission is needed to visit the nature reserves which are closed during the bird breeding season . Away from the three main channels the areas are rarely frequented with very few visitors . Nature tourism, however, has been greatly neglected, with, for example, a detailed plan prepared in 1982 by the Institute for Research on Ecology for Tourism of the Ministry of Tourism (together with the National Council for Scientific and Technical Research and the Academy of Sciences in Agriculture and Forestry) being ignored. General tourism development was encouraged, however, on the coast. More recently the beginnings of indiscriminate tourism organised by numerous tourist agencies is evident with 40 private agencies springing up in Tulcea. 쥁@