The Consequences of the Oder Flood in 1997 on the Distribution of Polycyclic Aromatic Hydrocarbons in the Oder River

Changes in the levels and spatial distribution of PAHs as a consequence of the Oder flood in the summer of 1997 were investigated in post‐flood sediments from the Oder River and the Oder Lagoon. The aim of this study was to identify sources of the PAH pollution and in particular investigate polluted sites (“hot spots”) in the most highly suspected locations of the drainage area. Molecular indices based on isomeric PAH ratios and the ratio of the parent PAHs to methylated PAHs were used to distinguish between the pollution sources. Elevated levels of PAHs were discovered in the post‐flood sediments of the Oder River in comparison to the average regional values. Elevated concentrations of PAHs were also found in fluffy layer samples taken from the Oder Lagoon and the Pomeranian Bight in late August. The highest concentrations of PAHs were observed near power plants or roads with heavy traffic. Most of the contamination originates from high temperature pyrogenic sources with some slight overlays of petrogenic sources. These increased concentrations of pyrogenic origin may be attributable to flooding of municipal and industrial waste disposal areas in the Oder River drainage.     

Distribution and Fate of Polycyclic Aromatic Hydrocarbons (PAHs) in Sediments and Fluffy Layer Material from the Odra River Estuary

The distribution and fate of polycyclic aromatic hydrocarbons (PAHs) were investigated in surface sediments (0...2 cm) and fluffy layer material of the internal and external coastal waters of the Odra river estuary (north-eastern Germany). The area includes the Odra Lagoon (Oderhaff), the Greifswalder Bodden, the Pomeranian Bight, and the Arkona Basin. Elevated concentrations were observed in the surface sediments of the internal coastal waters with highest concentrations in the Odra Lagoon. This indicates a significant contribution of river discharge to the contamination of sediments with PAHs. During the exceptional Odra flood in the summer of 1997 significantly higher concentrations of PAHs were found in the fluffy layer material of the Odra Estuary. The distribution of the individual PAH compounds varies widely depending on their structure and molecular weight. A concentration gradient of the lower molecular weight PAHs was found from the Odra Lagoon to the open sea areas. The concentrations decreased rapidly from the Oder Haff to the Arkona Basin. These results were found in both sediments and fluffy layer material. This is attributed to the degradation of the lower molecular weight PAHs during transport from the urban regions to the sedimentation basins. A decrease of this magnitude was not found for the higher molecular weight PAHs (i.e. benzo(a)pyrene) due to their higher persistence. An enrichment of these compounds was measured in the Arkona Basin.     

The exceptional Oder flood in summer 1997 — distribution patterns of the oder discharge in the Pomeranian Bight

The exceptional Oder flood in summer 1997 was a unique event in order to investigate the impacts on and the consequences for the ecosystem of the Baltic Sea of about 6.5 km³ additional water loaded with nutrients and contaminants and discharged within only 5 weeks. About 15 institutions participated in this investigation in both the Szczecin Lagoon and the Pomeranian Bight. The Baltic Sea Research Institute Warnemünde studied the water and nutrient inflow, the spreading of the Oder discharge, and the impact of the discharge on the ecosystem. The main topic of the presented investigations is a detailed study of the spatial and temporal spreading of the extreme river discharge in the Pomeranian Bight and the southern Baltic Sea by satellite data, ship observations and continuous buoy measurements as well as numerical modelling. The meteorological conditions were characterized by mainly easterly winds which guided the outflowing riverine water along the German coast into the Arkona Sea. The spatial and temporal development of the distribution patterns of the Oder discharge was monitored by about 80 Sea Surface Temperature (SST) images of NOAA satellites. Shipborne measurements showed that the vertical extent of the Oder plume ranged between 5 and 7 metres. The concentrations of inorganic nutrients, except higher silicate, were comparable to typical winter/early spring values (seasonal maximum) in this region. The high dilution effect of the flood water reduced the concentration of contaminants and thus, prevented a direct negative impact of trace metals and chlorinated organic compounds on the marine environment. Coupled physical-biochemical modelling in combination with SST-images demonstrated the temporal development and satellite data in the visible spectral range delivered the maximum extent of discharged river water into the southern Arkona Sea where a further western transport was limited by the upwelling region off Hiddensee. Thus, all detected effects of the Oder flood were confined to the Pomeranian Bight and the southern Arkona Sea, without long-term consequences for the ecosystem.     

Model Simulations of the Transport of Odra Flood Water through the Szczecin Lagoon into the Pomeranian Bight in July/August 1997

The Odra river flood of July through August 1997 transported a large additional volume of water into the Szczecin Lagoon area for a period of about one month. The dispersion of this water in the Szczecin Lagoon and Pomeranian Bight was simulated using the operational hydrodynamic model of the North Sea and Baltic Sea operated by the Federal Maritime and Hydrographic Agency of Germany (BSH). The model system receives as input meteorological forecast fields from the EUROPA model of the German Weather Service. As a result of the model simulation, the temporal development of the river plume can be described as follows: First the eastern part of Szczecin Lagoon, the Zalew Wielki, filled with flood water displacing θnormalρ Odra river water from that area. After about a week, Odra river flood water started to flow into the Pomeranian Bight. Its dispersion within Szczecin Lagoon was by no means uniform. The Kleines Haff, the western part of the Lagoon, was not much affected at first. When large labelled water masses had already left the Zalew Wielki area through the Swina river, at most only about half the water volume in Kleines Haff had been replaced by Odra flood water. In the Pomeranian Bight, the concentration was higher at the coast of Usedom – at least initially – than at the coast of Wolin. After 30 August 1997, northwesterly winds caused undiluted Baltic water to flow from the northern to the southern part of the Pomeranian Bight, pushing the water body marked, or distinguished, by Odra water eastward along the coast of Wolin. At the same time, outflow began from Kleines Haff through the Peenestrom into the Greifswalder Bodden. Due to light winds, and hence limited vertical mixing in summer, the proportion of freshwater in Baltic surface water reached about 50% in the southern Pomeranian Bight. Near Rügen, it fell below 10%. Within 2 months of stronger wind caused major shifts of the water bodies concerned. The scale considerations and model simulations discussed in this paper allowed qualitative estimates to be made in the course of the flood event, which were later confirmed by measurements, presented at a HELCOM (Helsinki Commission, Baltic Marine Environment Protection Commission) Scientific Workshop in January 1998.     

The Biological Quality of the Water of the Czechoslovak Part of the Oder River

The biology and purity of the water in three profiles of the Oder River in its upper stream on the Czechoslovak territory were investigated in the course of 1979… 1980. Zoobenthos, physical and chemical parametres, and microbiological germs were analysed. The bioseston was considered only briefly. On the basis of the presented material the Oder enters the Ostrava industrial agglomeration as a betamesosaprobic stream (Class I b of water purity), in spite of the fact that many sources of pollution can be found in this section of the river. Physical and chemical parameters can be assessed in a similar way. The Oder River belongs to Class III of water purity according to microbiological ratings.     

Adsorbable Organic Halogens (AOX) in Polish Rivers – Levels and Changes

This paper presents results of a study on the concentration of adsorbable organic halogens (AOX) in water samples of the Oder River and its tributaries collected from 1998 to 2002. The Vistula River water for AOX was analysed in the period 2001–2002. The investigated waters of the Vistula near the mouth (Kiezmark) were more contaminated with AOX than the Oder near the mouth (Widuchowa, Krajnik Dolny). In general, AOX levels in the Polish rivers are comparable to the values found in the European rivers, e.g. the Rhine and the Ton. The research has shown that AOX were correlated with pH, total suspended solids, and the riverine flow. No relation between dissolved oxygen and redox potential and AOX was found out. During the flood period AOX, inorganic halogens (TIX), and mineral substances (sulfates) were analysed.     

Strontium isotope identification of water mixing and recharge sources in a river system (Oder River,central Europe): A quantitative approach

This study uses Sr isotope composition (⁸⁷Sr/⁸⁶Sr) and Sr content of waters of the Oder, one of the largest rivers in central Europe, to fingerprint natural and anthropogenic contributions to its Sr budget and to evaluate water mixing processes in its hydrological system. It also demonstrates a simple method of quantifying natural and anthropogenic Sr inputs in the watershed. The method has potential for environmental and archaeological research because past Sr geochemistry of river water can easily be reconstructed. For the first time, a catchment‐scale impact of anthropogenic sources on the Sr budget of a middle‐size river is shown in a quantitative way. The water of the Oder is characterized by a relatively uniform Sr isotope composition, from 0.7100 to 0.7108, contrasting with strong variations in Sr concentration, from 0.25 to 1.27 mg/L. There is a general seasonal trend in variability, with waters becoming more radiogenic and dilute with respect to the Sr in the spring time. This Sr systematics differs significantly from the Sr budgets of the majority of the Oder tributaries that exhibit more radiogenic composition and systematically lower Sr concentrations. A mixing scenario in the Oder involves Sr contribution from four principal water sources: (a) shallow ground waters with Sr derived from near‐surface weathering of silicates, (b) moderately radiogenic mine waters from the Upper Silesian Coal Basin, (c) unradiogenic mine waters from the Permian sequence of the copper district, and (d) unradiogenic ground waters from shallow‐seated Palaeogene, Neogene, and Mesozoic aquifers. The Sr budget of the Oder is primarily controlled by inputs of dissolved Sr from anthropogenic sources, which overprint the natural background, controlled by geology. Thus, about 47.5% of Sr originates from agriculture, industrial, and municipal additions, 31.5% from mine water inputs, and only 21% from natural sources, that is, rock weathering and atmospheric precipitation. Reconstruction of the past Sr chemistry of the Oder reveals that its present‐day Sr isotope composition is temporary and significantly different from that of the preindustrial times.     

Levels and patterns of polychlorinated dibenzo-p-dioxins, dibenzofurans and biphenyls in surface sediments from the western Baltic Sea (Arkona Basin) and the Oder River estuarine system

Surface sediment samples were collected from the western Baltic Sea (Arkona Basin) and the Oder River estuarine system in May and August 1995 and analysed for polychlorinated dibenzo-p-dioxins, dibenzofurans and biphenyls. Contents of PCDF (sum) and PCDD (sum) varied from 2.5 to 820.0 pg g⁻¹ dw and from 12.7 to 2991.0 pg g⁻¹ dw, respectively. PCB contents (sum of 23 congeners) ranged between < 130.0 and 16267.0 pg g⁻¹ dw. Only slight variations in PCDF/D and PCB contents on dry weight basis were found between the Oder River estuarine system and the open Baltic Sea. TOC-normalization of the data showed an approximately homogen PCDF/D distribution in the study area. The distribution pattern for PCDF/D and PCB may be attributed to high sediment dynamics combined with transport processes from the temporary sedimentation basin (Oderhaff) to the deeper parts of the Baltic Sea.     

Dynamics of the Oder river plume in the Southern Baltic Sea: satellite data and numerical modelling

The Oder river discharge into the Pomeranian Bight of the Baltic Sea was investigated in a combined study using satellite data, numerical modelling and shipborne measurements. The aim was to understand the dynamical processes forming the freshwater distribution patterns during the prevailing winds. From an analysis of typical distribution patterns of the river discharge in relation to the main wind directions and in comparison to seasonal wind statistics, the two main transport directions were determined. The prevailing westerly winds produce an onshore transport and a downwind coastal jet which transports the river water along the Polish coast, in certain cases over a distance of 300 km to the Gdansk Bay. During a period of stable westerly winds in June 1994, the calculated time scale for a water transport over 250 km corresponded to the observed time of 12 d. In spring, the period of maximum river runoff, easterly winds dominate and transport occurs along the German coast into the Arkona Sea. The river water is guided by upwelling processes in front of the Polish coast. During occasional north-easterly winds stable plumes form in front of the Swine river mouth; this occurred in May 1991 for several days. The numerical model showed that the stability of the plume is caused by an interaction between the alignment of the coast, the large-scale circulation in the north, the buoyancy of the freshwater and the Coriolis effect. The underlying anticyclonic eddy is indicated by warm rings in a high resolution Landsat Thematic Mapper scene. From the different datasets the range of the spatial and temporal scales of a stable plume were determined. The volume varied between 0.14 and 0.9 km³, and the suspended matter and chlorophyll load between 1120 and 7200 t and 2.8 and 18 t, respectively. These values are important for ecological budget calculations in turnover process studies.     

Transport and dispersion of particulate Hg associated with a river plume in coastal Northern Adriatic environments

The role of suspended particulate matter (SPM) as an important carrier of mercury (Hg) dispersed into the Gulf of Trieste and in the adjacent Grado lagoon (Northern Adriatic Sea) was studied during a high Isonzo River inflow and the resulting river plume formation. Despite the fact that extreme flood events are rare during the year, they account for most of the PHg influx (37-112 ngL(-1)) into the Gulf of Trieste. When the river plume is diverted to the SW under the influence of an E-NE wind, the tidal flux acts as a "transport belt" carrying the PHg, mostly inorganic, into the Grado lagoon. A preliminary estimation indicates that the amount of PHg entrapped in the lagoon basin following a tidal semi-cycle accounts for 1.4 kg/12h, which corresponds to about 49% of the total Hg carried by the tidal flow. These findings should be considered in future remediation strategies in the lagoon environment.     

Estuarine modification of nutrient and sediment exports to the Great Barrier Reef Marine Park from the Daintree and Annan River catchments

Nutrient and suspended sediment concentrations were measured in the dry season and during the rising and falling stages of flood events in the Annan and Daintree rivers to estimate catchment exports. These flood events were also sampled along the salinity gradient in the estuary and nearshore shelf to quantify the modification of terrestrial sediment and nutrient loads as they pass through estuaries into the Great Barrier Reef lagoon. In the Daintree River TSS concentrations were found to increase between the catchment and the estuary plume. The source of TSS may have been scour of the estuarine channel or from land use in the catchment of the lower estuary. In the dry season nitrogen enters the Annan and Daintree estuaries predominantly in the form of PON and DON in roughly equal proportions. Nitrogen exports to the GBR are mostly in the form of DON. In the wet season the majority of nitrogen enters the estuaries as DON and leaves as PON. Nitrogen removal in the estuaries and plumes appears to be biologically mediated once suspended sediment concentrations decrease to a point where phytoplankton growth is not light limited. In the dry season phosphorus enters and leaves the estuaries primarily in organic form. PIP is the dominant form of phosphorus in river water, but leaves the estuary more evenly distributed between all forms. These estuarine processes result in less nitrogen and phosphorus being delivered to the GBR lagoon than is exported from the catchment. The differences between these estuaries highlights the need for further work to explore modifications in estuaries that drain into the Great Barrier Reef lagoon.     

Occurence and Transport of Organic Micro-contaminants in Sediments of the Odra River Estuarine System

Over ninety surface sediment samples (0...3 cm) were collected in the Odra river estuarine system – from the Oderhaff, the Pomeranian Bight, the Peenestrom, the Greifswald Bodden – and the Arkona Basin between 1994 and 1996 and analysed for polychlorinated dibenzo-p-dioxins, dibenzofurans (PCDD/F) and biphenyls (PCB), and p,p′-dichlorodiphenyl-trichloroethane (DDT) including their metabolites. The contents of all investigated organochlorines in the sediments of the western part of the Oderhaff (Kleines Haff) were only slightly higher and more homogenously distributed compared to the values of the Pomeranian Bight and the Greifswald Bodden. PCB contents (sum of 23 congeners) in surface sediments ranged between <130 and 9 550 pg/g (given for dry weight, dw). The results of individual PCB congeners showed that high contents of hexa- and heptachlorinated compounds (PCB 138, 153, 180) were present in the entire area investigated. Generally, low levels of PCDD/F were found in surface sediments of the Odra river estuarine system due to small industrial activities in the catchment area. Contents of PCDF (sum) and PCDD (sum) varied from 2.5 to 820 pg/g (dw) and from 13 to 2 991 pg/g (dw), respectively. The congener contents of PCDF showed a nonuniform picture between the Oderhaff and the Arkona Basin. In contrast, the congener profiles of PCDD showed approximately similar patterns at nearshore and offshore stations, with highest values of OCDD (octa CDD). We assume that most of the particulate-bound micro-contaminants (PCB, PCDD/F) are deposited in the eastern part of the Oderhaff (Stettin Lagoon), which acts as a temporary trap and opurificationπ basin for the suspended particulate matter (SPM). One pathway for further transport of the particles seems to be the way on a small sedimentation strip along the island of Usedom via the “Saßnitz-trough” into the deeper parts of the western Baltic Sea.     

Flocculation and the loss of sediment from the Po River plume

In October 2000, a 100-year flood event in the Po River resulted in the formation of a fine-grained sediment deposit extending up to 10 km from the river mouth. Soon after this event, and for a subsequent period of 2 years, box cores were collected on a grid of stations off of the Po Delta to observe the evolution of the flood deposit. Using a process-based parameterization of the disaggregated inorganic grain size distribution, the evolution of the surficial sediment on the Po shelf since the 2000 flood has been interpreted in the context of particle flocculation dynamics. This method produces estimates of floc limit, the diameter at which the flux of single grains to the seabed equals the flux of flocs, and floc mass fraction, the amount of material deposited as flocs. Floc limit depends on the extent of flocculation in suspension, and floc mass fraction describes the extent of flocculation in the sediment. Immediately after the flood, these two parameters were high at stations located beneath the path of the flood plume as observed in satellite images. The occurrence of a highly flocculated deposit below the path of the plume leads to two hypotheses: (1) the high sediment concentration in the river flood plume produced extensive sediment flocculation in the plume and (2) post-depositional remobilization of sediment delivered from the plume to the seabed was limited in the relatively low-energy environment of the Po prodelta. Floc limit and floc mass fraction estimated from bottom sediment sampling 3 and 10 months after the initial sampling were lower, indicating that during normal discharge, flocculated fine-grained sediment from the Po River settles close to the mouth, leaving only a small amount of material in suspension in the plume for direct deposition onto the prodelta. These findings are consistent with laboratory studies of suspended sediment that show that sediment concentration and turbulent energy exert dominant control on the extent of flocculation and the loss of sediment from suspension.     

Modelling the impact of a La Niña event on a South West Pacific Lagoon

In view of increasing environmental awareness and biodiversity conservation, understanding the main forcing mechanism driving biogeochemical cycles in coral reefs and lagoon coastal areas is a priority. La Ni?a events cause unbalanced situations in the Equatorial Pacific and result in enhanced precipitation in South West Pacific coastal areas. We investigated the impact of heavy rainfalls during the 2008 La Ni?a event on the New Caledonia lagoon using a 3D coupled on-line hydrodynamic-biogeochemical model. Simulations and data showed that the whole lagoon was impacted by river inputs and stronger hydrodynamics, enhancing chlorophyll-a concentration by a factor between 1.7 and 1.9. The coupled model provided new insights into plume transport, highlighting that eastern plumes can be advected northwards or can reach the South West Lagoon, depending on the balance between regional, tide-induced, and wind-induced surface currents. It also provided a synoptic view of lagoon biogeochemical-hydrodynamic response, when remote sensing data are not available due to cloud coverage.     

Transfer of organic contaminants to the Baltic in the Odra Estuary

This paper describes the transfer of organic contaminants to the sea, using PAHs (12 compounds) and PCBs (11 congeners) as examples, through a eutrophicated coastal lagoon (Szczecin Lagoon, on the Polish-German border). The transfer of contaminants study was based on their concentration in recent sediments (0-10 cm), in relation to different environmental conditions such as temperature, salinity, turbidity, oxygen and nutrients in water, hydrological conditions, organic carbon and biomarkers (pigments and their derivatives) in sediments. Results include the data obtained between 1994 and 2000, also those on before and afterwards the great flood in July 1997, at different stations in the Lagoon and the adjacent Pomeranian Bay. The results indicated that the eutrophic estuary of the shape of lagoon acts as an effective trap for the hydrophobic organic pollutants. The abundance and taxonomy of plankton as well as detritus derived from it play an important role in bonding the studied compounds. The salinity gradient in the lagoon has a significant influence upon deposition of the pollutants from the water column to the sediments and the residence time of the compounds there depends strongly on oxic-anoxic status of the sediments and the strength of interaction with sediments resulting from polarity, the type and stability of associates formed, as well as on hydrological conditions. We conclude that eutrophication in this area prevents pollution of the sea to some extent.     

Temporal and spatial variability of extreme river flow quantiles in the Upper Vistula River basin,Poland

Temporal and spatial variability in extreme quantile anomalies of seasonal and annual maximum river flows was studied for 41 gauging stations at rivers in the Upper Vistula River basin, Poland. Using the quantile perturbation method, the temporal variability in anomalies was analysed. Interdecadal oscillating components were extracted from the series of anomalies using the Hilbert‐Huang transform method. Period length, part of variance of each component, and part of unexplained variance were assessed. Results show an oscillating pattern in the temporal occurrence of extreme flow quantiles with clusters of high values in the 1960–1970s and since the late 1990s and of low values in the 1980s and at the beginning of the 1990s. The anomalies show a high variability on the right bank of the Upper Vistula River basin during the summer season with the highest values in catchments located in the western and south‐western parts of the basin. River flow extreme quantiles were found to be associated with large‐scale climatic variables from the regions of the North Atlantic Ocean, Scandinavia, Eastern Europe, Asia, and, to a lesser extent, the Pacific Ocean. Similarities between temporal variability of river flows and climatic factors were revealed. Results of the study are important for flood frequency analysis because a long observation period is necessary to capture clusters of high and low river flows.     

Pollution effects of the Tuy River on the central Venezuelan coast: Anthropogenic organic compounds and heavy metals in Tivela mactroidea

Bivalve samples were collected at seven sampling stations located between the town of Machurucuto and the Bay of Higuerote, Venezuela, covering approximately 70 km of coastline. Samples were collected both east and west of the Tuy River mouth, which has a plume known to move in a north-westerly direction. Petroleum hydrocarbons, both aliphatic (n-alkanes and UCM) and polyaromatic (PAHs), were detected and quantified in the samples. These hydrocarbons were found to be primarily derived from fossil fuels. Halogenated organics consisted mostly of polychlorinated biphenyls (PCBs) and some chlorinated pesticides, primarily of the DDT group. Heavy metals such as Pb, Cu, Ni, Zn, Cr and Cd were analysed in the samples. The results clearly show the influence of the Tuy River plume on the water quality of the coastal zone, particularly that located west of the river mouth. One sampling station, located just east of the river mouth, also showed significant influence from the river plume.     

Observation of the supercritical Pearl River plume front under the downwelling-favorable winds

For the Pearl River plume, the supercritical, distinct plume front appears in downwelling-favorable winds, which is easily observed due to the distinct boundary between the plume water and the ambient water. In this paper, in situ and satellite observations of a plume front are utilized to explore the Pearl River plume front properties under the downwelling-favorable winds. Field observations clearly show frontal structure, especially the two-layer structure in the plume water and the downward-motion of water in the frontal region. The Advanced Synthetic Aperture Radar(ASAR) images are also analyzed to unveil the plume front: there is a white stripe on the west side out of the river mouth under downwelling-favorable winds, which is identified as a supercritical plume front, and the width of the plume front is about 250 m. The normalized velocity gradient shows the intense velocity convergence in the front region. Also, analyses of ASAR images imply that the river discharge plays an important role in controlling the location and shape of the front.     

汉江上游安康东段全新世古洪水沉积学与水文学研究

通过沿汉江上游河谷深入的考察,在安康东段发现了典型的古洪水滞流沉积剖面.通过采集样品、实验分析,确定它们是古洪水在高水位滞流环境当中的悬移质沉积物.根据地层对比、OSL测年和相关文化层年代,确定它们分别记录了发生在BL+AL与YD事件转折阶段(12500 a B.P.)的古洪水事件和发生在1000-900 a B.P.(1000-1100AD),即北宋后期的洪水事件.根据古洪水SWD的高程恢复其洪峰水位,结合相关参数,利用面积比降法计算恢复流量.结果表明在万年尺度,汉江上游古洪水洪峰流量介于35970~47400 m³/s之间.同时,利用2010年大洪水洪痕恢复计算洪峰流量,对古洪水洪峰流量计算结果进行了验证.进而结合历史洪水和观测洪水数据,获得了汉江上游万年尺度洪水洪峰流量与频率关系.这为汉江上游的水利水电和交通工程建设以及沿岸城镇防洪减灾提供了基础性数据.     

泄洪对典型有机污染物迁移转化行为的影响——以丹江口水库为例

随着高坝水库的建设,大坝泄洪雾化对生态环境的影响已得到较多研究,而泄洪雾化对污染物迁移转化行为的影响尚未引起关注.本研究于2019年对丹江口大坝泄洪期间坝前和坝下多个断面进行了采样调查,分析了水体中16种多环芳烃(PAHs)和6种邻苯二甲酸酯(PAEs)的浓度.发现泄洪后坝下水体中检测出的8种PAHs和5种PAEs浓度...