Characteristics of water and alluvial transit through the Danube Delta
| Autor: | Bondar Constantin |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2019 |
| Předmět: | |
| Zdroj: | Scientific Annals of the Danube Delta Institute, Vol 24, Pp 225-232 (2019) |
| Druh dokumentu: | article |
| ISSN: | 1842-614X 2247-9902 |
| DOI: | 10.7427/DDI.24.24 |
| Popis: | A part of the Danube’s water that runs through the Black Sea to the Danube Delta’s main rivers, enters a variety of ways (canals, gorges, and river spills) inside the Danube Delta and the Razelm-Sinoe Lagoon Complex, Black. The measurements showed that the Danube water access to the Delta takes place on the upstream half of the arms, and the evacuation takes place halfway downstream. Knowing the transit of water and alluviums through the hydrographic units within the Danube Delta is of particular importance to the Delta habitat. Danube water transits the Danube Delta’s interior through the hydrographic units Sontea-Furtuna, Matita-Merhei, Gorgova-Uzlina, Puiu-Rosu and Dranov-Razelm. Based on a hydrological model elaborated by the author, the water flows and the volumes of water entering and leaving the Danube Delta hydrographic units were determined. The results of the calculations showed that the largest water transit through the Danube Delta is through the hydrographic units Sontea-Furtuna and Matita-Merhei, followed by Gorgova-Uzlina, Puiu-Rosu and Dranov-Razelm. The dates of the measurements of the Danube alluvial flows, carried out in the past and to this day, allowed to know the evolution of the concentration of the suspended alluviums at the entrance to the Danube Delta. Data processing results in a decrease in average annual concentrations of Danube sludge concentrations from average values of about 300 mg/m3 in 1840 to about 80 mg/m3 in 2014. The overall trend of the decrease in time of concentrations of Danube alluvial sediments was mainly due to the hydrotechnical arrangements made in time in the Danube river basin and was accentuated after the barrage of the Danube bed at Iron Gates 1 and 2 in the years 1971 and 1984. The fluctuations in the Danube Delta concentrations in the Danube Delta in the Danube Delta caused time to diminish the access of the river valleys within the Danube Delta and to diminish the Danube delta between the arms. Thus it results that the process of clogging of hydrographic units subject to alluvia is very slow, equal to about 1.26 mm/year in the hydrographic unit Sontea - Storm and 0.51 mm/year in the hydrographic unit Gorgova - Uzlina. |
| Databáze: | Directory of Open Access Journals |
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