Long-term changes of submerged macrophytes in the Lower Danube Wetland System

摘要: Transition towards hypertrophy has affected biodiversity and productivity of most aquatic wetland systems in the Lower Danube Wetland System (LDWS) over last two decades. The macrophytes have been deeply involved ecosystem reorganization these circumstances. Representative shallow lakes channels located river floodplain delta were studied this period terms space distribution, diversity, species composition, primary production main hydrogeomorphic features (morphometrical physico-chemical parameters). Changes submerged vegetation dynamics along successive decades after 1980 included diminishing areas about 50% Delta, restructuring producers by suppressing weed some or parts decreasing richness to few populations with upright floating growth strategy. Biomass showed different trends, from severe reduction periods marked increase other ones, provided a changed simplified structure, generally dominated Ceratophyllum demersum L. Potamogeton species. It was concluded that eutrophication effects are maintaining, modulated diverse response mechanisms developed macrophytes. Finally, lessons be learned for management macrophyte-dominated framework redesigning LDWS structures emphasized on basis large scale long-term prospect River Black Sea Basins.