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Generally, water quality involves the water-s physical-chemical and biological attributes that depend on the natural surrounding environment and anthropogenic impacts. Through the years, the river water quality in the Sf. Gheorghe Branch has been subjected to various hydro-sedimentary impacts, due to the anthropogenic meander cut-off plans initiated for navigational objectives. In this study, the Sf. Gheorghe Branch water quality evaluation was performed using in-situ observations, measurements, and datasets provi...

The paper presents the results of the water quality of the St. George branch, one of three Danube River distributaries, using the combined physical and chemical analyses from June 2017. Three cutoff meander reaches (the Mahmudia, Upper Dunavat and Lower Dunavat meanders) were selected to assess the water ecological state. The cut-offs of the meanders by navigational canals since 1984-1988 caused significant changes in the distribution of the water discharge. Water samples were acquired throughout several cross-sec...

The study presents a detailed analyse of the morpho-dynamic processes of the main two bifurcations of the Danube River within its delta, at Ceatal Izmail and Ceatal St. George. The first bifurcation of the Danube, called Ceatal Izmail; here the river divides into two distributaries: a northern one, the Chilia (Kilia), and a southern one, the Tulcea. Forking to the right at Ceatal Izmail (Mile 43), the Tulcea distributary stretches further to 17 km to the second main hydrographic knot Ceatal Sfantu Gheorghe (St. Ge...

Heavy mineral concentrations formed in fluvial deposits present the signature of the mineral provenance and of the hydraulic sorting during transport and accumulation. The sedimentary discharge of the Danube River has been preferentially deposited due to the mineral physico-chemical properties, such as size, morphology and density, as well as local hydrodynamic factors. Besides these natural aspects, the recent modifications of the Danube and its deltaic branches are associated with a significant remodelling of th...

Taking into account the sedimentation features since the last 5 decades, considerable anthropic modifications on the Danube channel are present, as the debris composition varies concerning the proportion of terrigenous minerals, lithoclasts, bioclasts and organic matter. Since the 7th decade of the last century, marked by the construction of most hydrological power plants on the Danube, Olt, Jiu, Cerna and other major rivers, a significant change of the sedimentary volume brought downstream by the Danube is assume...

Most of the suspension matter transported by rivers derives from the riverbed erosion. Complementary, the anthropogenic factor is responsible for the introduction of significant amounts of sedimentary material, especially suspended, but also dissolved material. In most cases, the distinction between naturally occurring materials and anthropic ones is almost impossible to achieve due to the complexity of the erosion processes. The suspended sediments concentration (SSC) and discharges were analyzed in the Danube De...

This article presents the results of studies of the hydrodynamical and sedimentological conditions of the Sulina Channel, the middle distributary of the Danube within its delta. One field campaign (at low waters) in September 2019 was conducted to analyse the geometry, the sediment composition and hydraulic conditions of the channel. During the field campaign, the measured water mean velocity was from v = 0.01?0.54 m.s-1 for a water discharge (measured upstream, at the bifurcation, knot Ceatal St. George) of 698 m...

In the Danube delta, on the Sulina Channel, the morphology and bedforms characteristics have been investigated. 3D bathymetry, flow velocity, and bed sediments data have been acquired, in order to investigate the dynamic of the bedforms, the distribution of the water, and their influence against the river bed. A single observation (in May 2019) was made regarding the geometry, sediment composition and hydraulic conditions under which the dunes grew and decomposed. The investigation focuses here mostly on the geome...

The coastal retreat in touristic areas concerns many sectors along the Romanian Black Sea shore; it usually requires programmes for beach nourishment, and consequently, large amounts of proper sand are necessary to be available for such activities. In order to minimize the effort for searching offshore sand, we conducted seismo-acoustics researches and some other archived data have been used during these researches, both for planning the sea works and during the integrated interpretation of the data. The results o...