STRATEGIES FOR THE SUSTAINABLE DEVELOPMENT IN THE DANUBE DELTA IN ROMANIA, UKRAINE AND MOLDAVIA

摘要

Danube Delta is the largest humid zone in Europe. The diversified structure of the natural ecosystems, most of which were unaffected by human activity, have made the Danube Delta, together with the Razelm-Sinoe lagoon complex, a Biosphere Reserve. It has also been included on the list of International Natural and Cultural Heritage, and in the Ramsar Convention. As a direct effect of the flooding areas disappearance, the Danube Delta's capacity to retain nutrients has increased sharply since the 1980s. It is currently affected by eutrophycation, which has led to the reduction or loss of low water macrophitae. to changes in the range of periphytic and epiphytic algae, and to the spreading of rival species favoured by the nutrients in excess (for example, the blue-green bacteria Cyanophyta). Apart from the losses caused by eutrophycation, the Delta's biodiversity was and still is affected by the changes in (or destruction of) the habitats, by changes in the hydrological patterns. The latter are due to the creation of man-made channels or meander interruption, by transforming large areas into agricultural or fishing zones, or by the change in water quality (transformation of the Razelm lagoon into a fresh water lake).