Cruise Report R.V. POSEIDON POS283

25.01. - 05.03.2002 Port Calls: Southampton, UK, 30.01.-02.02.2002 Pta. Delgada, Azores, Portugal, 10.02. – 11.2.2002 Las Palmas, GC, Spain, 26.02.-01.03.2002 Las Palmas, GC, Spain, 05.03.-08.03.200

Chlorinated biphenyls and p,p'-DDE in Mediterranean surface waters

Individual chlorobiphenyls (CBs) and p,p'-DDE were determined in solution and suspension in surface transects of the open Mediterranean Sea in 1987. Large volumes of sea water (1400—1700 dm3) were analyzed. Concentrations of CBs were low in solution (<5 pg/dm3) and in suspension (<60 pg/dm3). Values for their sum (XCB) were 1.7-43.9 and 190-615 pg/dm3, respectively. Compositions of the CB mixtures in solution as well as those in suspension were very similar in the various transects, but considerable differences were present between solution and suspension in each transect. It was attempted to interpret these differences in terms of molecular characteristics (octanol-water distribution coefficients, Kaw). The resulting plots of log Kovl vs. the apparent distribution coefficient (log K&) gave evidence for the uptake of CBs by suspended particles, followed by sedimentation out of the surface layer. Concentrations in solution were much lower (1-2 orders of magnitude) than those reported before. This may result from improvements in the sampling and analytical techniques. No clear evidence for significant local sources of these compounds was detected in the surface waters, as the levels in solution were very similar to the very low concentrations in the adjacent open Atlantic

Bilanzierung und Quantifizierung des Chlorbiphenyl-Eintrages in das Oderhaff

Under the EC sponsored research project ODER (Oder Discharge-Environmental Response) first investigations have been carried out to estimate the chlorinated biphenyls (CB) input into Oderhaff via the Oder river. For this purpose, vertical profiles of CB content and composition were analysed on samples of three sediment cores. In two water samples, the content of suspended particulate material as weil as the particulate CB content and congener-specific composition were measured. In the Oderhaff the CB concentrations of particulate material were between 700 to 800 pg/dm3. Significant differences in the composition of the components were not observed. In sediments, CB contents were as high as 17 to 24 ngig dry weight in near surface sediment layers. They decreased with increasing sediment depth and were below detection limits at 15 to 21 cm depth. Based on the size of the 49 accumulation area and related hydrographic conditions, we estimated an input of 95 kg into the Oderhaff for the last 65 years since the onset of CB production. Applying the present prevailing conditions, we calculated an average transport of about 825 kg CB by the Oder river during this period. Comparing these two estimates, we observed that at least 15 % of the CB transported by the Oder river was deposited in the Oderhaff. The remaining 85 % (-730 kg), have been further transported into the South Pomeranian Bight and Southern Baltic Sea

Chlorinated Biphenyls and p,p\u27-DDE in Mediterranean Surface Waters

Individual chlorobiphenyls (CBs) and p,p\u27-DDE were determined in solution and suspension in surface transects of the open Mediterranean Sea in 1987. Large volumes of sea water (1400—1700 dm3) were analyzed. Concentrations of CBs were low in solution (<5 pg/dm3) and in suspension (<60 pg/dm3). Values for their sum (XCB) were 1.7-43.9 and 190-615 pg/dm3, respectively. Compositions of the CB mixtures in solution as well as those in suspension were very similar in the various transects, but considerable differences were present between solution and suspension in each transect. It was attempted to interpret these differences in terms of molecular characteristics (octanol-water distribution coefficients, Kaw). The resulting plots of log Kovl vs. the apparent distribution coefficient (log K&) gave evidence for the uptake of CBs by suspended particles, followed by sedimentation out of the surface layer. Concentrations in solution were much lower (1-2 orders of magnitude) than those reported before. This may result from improvements in the sampling and analytical techniques. No clear evidence for significant local sources of these compounds was detected in the surface waters, as the levels in solution were very similar to the very low concentrations in the adjacent open Atlantic

Scientific Program of Merian-Cruises No. MSM01 /1 – 3

Die inhaltlichen Schwerpunkte der drei ersten Reisen des F.S. Maria S. Merian spannen sich von biogeochemischen Unter-suchungen der mittleren und nördlichen Ost-seebecken über Studien von Sedimentologie und Sedimenttransport in der westlichen Ostsee bis zu Untersuchungen der Tiefsee-biogeochemie im Golf von Cadiz. MSM01/1a-c: 16.02.-20.03.2006 Warnemünde – Stockholm – Helsinki-Warnemünde Die erste Reise untersucht auf drei Fahrtab-schnitten Auswirkungen der redox-bedingten Biogeochemie in Wechselwir-kung mit externen Stoffeinträgen in den zentralen und nördlichen Becken der Ostsee. Schwerpunkte sind die Funktion der nördli-chen Ostsee als Senke oder Transfergebiet für terrestrisch eingetragene Verbindungen, die Funktion mikrobieller Gemeinschaften im Eis und der Atmosphäre/Wasser–Austausch von Gasverbindungen. MSM01/2: 27.03. – 06.04.2006 Warnemünde - Warnemünde Die zweite Fahrt untersucht oberflächennahe Sedimente in Mecklenburger Bucht, Großem Belt, südlichem Kattegat, Arkonabeckens und nördlichem Bornholmbecken bezüglich ihrer Verteilung, Zusammensetzung und ihres Transportpotentials. MSM01/3: 27.03. – 06.04.2006 Kiel – Cadiz - Lissabon Die dritte Reise führt nach einem einwöchi-gen technischen Aufenthalt in Rostock und Kiel in den Golf von Cadiz mit Untersuchungen von biogeochemischen Stoffumsätzen, Fluid Flow und spezifischen Ökosystemen in der dortigen Schlammvulkanprovinz.The focus of the first three voyages of RV Maria S. Merian ranges from biogeochemcal investigations of the mid and northern basins of the Baltic Sea, to studies of sedi-mentology and sediment transport in the western Baltic Sea and investigations of deep sea biogeochemistry in the Gulf of Cadiz. MSM01/1a-c: 16.-27.02.2006 Warnemünde – Stockholm – Helsinki – Klaipeda - Warnemünde The first voyage with three legs investigates the particular impact of redox-controlled biogeochemistry in relation to external ma-terial supplies in the central and northern basins of the Baltic Sea. Emphasis is laid on the function of the northern Baltic Sea as a sink or transfer area for compounds with a terrestrial origin, the functioning of micro-bial ice-communities, and the sea-atmosphere exchange of gases. MSM01/2: 27.03. – 06.04.2006 Warnemünde – Warnemünde The second voyage focuses on near-surface sediments of the Mecklenburg Bight, the Great Belt, the Arkona Basin and the north-ern Bornholm Basin as to their respective distribution, composition and transport potential. MSM01/3: 27.03. – 06.04.2006 Kiel – Cadiz - Lisbon The third voyage, after 1 week in Rostock and Kiel port for technical purposes, will conduct studies on biogeochemical fluxes, fluid flows and specific ecosystems within the mud volcano province in the Gulf of Cadiz

Evidence for dissolution of fatty acids in sediment traps: impact on flux estimates

The effect of dissolution from particulates into the supernatant solution in sediment trap sample cups has been measured for fatty acids. A mooring array with time series sediment traps was deployed in the northeast Atlantic Ocean (59°N, 21°W) for 14 months. Selected representative samples from the trap at 2200 m (poisoned with NaN3) were analyzed for total and free fatty acids in both the solution and particulate phase by means of gas chromatography‐mass spectrometry with an ion trap detector. The flux contribution of the dissolved total fatty acids (∑ DTFA) was found to be between 15 and 75% of the total flux (∑ TTFA, sum of the fluxes of total fatty acids in both particles and supernatants). Dissolved free fatty acids (∑ DFFA) represented 25–88% of the total flux of free fatty acids (∑ TFFA). Absolute concentrations of total and free fatty acids in both compartments are discussed in terms of the processes controlling the distribution between the two phases, for example, readsorption. Sample handling, poisoning, bacterial activity, and swimmers may also affect fatty acid distribution. Flux data (sum of particulate and dissolved fluxes) are presented for individual fatty acids. Also, the degree of dissolution of individual fatty acids is shown for one sample (dissolved fraction ranging between 16 and 98% of total flux)

Colorimetric Chemical Differentiation and Detection of Phosphorus in Eutrophic and High Particulate Waters: Advantages of a New Monitoring Approach

Phosphorus (P) is a key factor forcing eutrophication in limnic and marine systems, and all monitoring programs for water quality accordingly include P determinations. However, traditional monitoring does not allow an analysis of the different components involved in the P cycle taking place in the water column. Nonetheless, the implementation of measures addressing eutrophication requires a full understanding of the processes involved in the transformation and transport of P, in all its chemical forms. In this study, the P categories present in a river and its estuary in northern Germany, which discharge into the Baltic Sea, were characterized. Using the molybdenum blue method we found that the classification of P into the traditional fractions (DIP, DOP, POP) applied in the ocean cannot be applied to turbid waters such as rivers because interferences between the fractions seems to occur. Therefore a new nomenclature has been introduced. In addition to total phosphorus (TP) and dissolved molybdate-reactive phosphorus (DRP; previously referred to as inorganic phosphorus), dissolved non-molybdate-reactive phosphorus (DNP), particulate molybdatereactive phosphorus (PRP), and particulate non-molybdate-reactive phosphorus (PNP) were distinguished. The high spatial and temporal variations in the proportions of these forms with respect to the TP concentration well-demonstrate the complexity of the P cycle and the involved P fractions and emphasize the need for expanded monitoring approach. The potential of eutrophication could be underestimated if not all P categories were considered. With the new operational nomenclature the common and standardized molybdenum blue reaction could be used to implement the analysis of various P components into regular monitoring programs

In situ Determination of Nitrate and Hydrogen Sulfide in the Baltic Sea Using an Ultraviolet Spectrophotometer

Evaluating the health status of marine ecosystems becomes ever increasingly important especially against the backdrop of rising pressures from human activities. This is true especially for coastal seas such as the Baltic Sea that is surrounded by highly industrialized countries. Nutrients and pollutants such as nitrate and hydrogen sulfide, which have a major impact on ecosystem functioning, are two of several key environmental indicators for assessing the status of natural waters, and therefore of considerable interest. The frequency and the spatial coverage of the nitrate and hydrogen sulfide measurements are currently limited by the cost of the laboratory analysis and personnel. Optical in situ sensors can help to overcome this challenge by allowing reagentless and fast detection of dissolved chemical species. A chemical-free optical sensor has been used for direct and simultaneous measurements of both key parameters, and the results were compared with traditional methods. The data were collected during an observational program conducted in the Baltic Sea in February 2018. We used the OPUS UV spectral sensor, which was deployed for the first time in coastal waters, in combination with a deep-sea telemetry system to enable near-real time measurements during CTD profiling. Data processing was carried out using a multiple linear regression procedure. Measurements from both OPUS and on-board analysis were in good agreement. The results showed, that in situ UV-VIS spectrophotometry provides the capability to determine the concentration distributions of nitrate and hydrogen sulfide in the brackish waters of the Baltic Sea