ALBERT

Description: El Niño–Southern Oscillation (ENSO) in the Pacific and the analogous Atlantic Niño mode are generated by processes involving coupled ocean–atmosphere interactions known as the Bjerknes feedback. It has been argued that the Atlantic Niño mode is more strongly damped than ENSO, which is presumed to be closer to neutrally stable. In this study the stability of ENSO and the Atlantic Niño mode is compared via an analysis of the Bjerknes stability index. This index is based on recharge oscillator theory and can be interpreted as the growth rate for coupled modes of ocean–atmosphere variability. Using observational data, an ocean reanalysis product, and output from an ocean general circulation model, the individual terms of the Bjerknes index are calculated for the first time for the Atlantic and then compared to results for the Pacific. Positive thermocline feedbacks in response to wind stress forcing favor anomaly growth in both basins, but they are twice as large in the Pacific compared to the Atlantic. Thermocline feedback is related to the fetch of the zonal winds, which is much greater in the equatorial Pacific than in the equatorial Atlantic due to larger basin size. Negative feedbacks are dominated by thermal damping of sea surface temperature anomalies in both basins. Overall, it is found that both ENSO and the Atlantic Niño mode are damped oscillators, but the Atlantic is more strongly damped than the Pacific primarily because of the weaker thermocline feedback.

Description: Never in the last 2,000 years was the Atlantic Water entering the Arctic in the Fram Strait between Greenland and Svalbard as warm as today. This was revealed by a study of marine sediments from the western Svalbard continental margin which was led by researchers from IFM-GEOMAR.

Description: 18.10. - 25.10.2011

Description: Dates of Cruise: 13. September to 19. September 2011 Projects: Student course in physical oceanography. Areas of Research: Physical oceanography Port call: Kiel – Warnemünde – Kiel

Description: Seismic oceanography is a new field in marine research combining expertise of proven geophysical methods with classical physical oceanography to get more insight into physical processes in the water column. An interdisciplinary working group at IFM-GEOMAR has sucessfully used the in-house expertise for deep ocean investigations.

Description: Tens of thousands of submarine volcanoes, so-called seamounts, with heights of more than a few hundred meters, exist in the world ocean. The Cape Verde archipelago is of volcanic origin and includes several prominent seamounts, which can give important information on the origin of submarine intraplate volcanism.

Description: Globally averaged sea level has risen by just under 10 cm during the last 50 years as a consequence of global warming. The rise, however, is not uniform, neither in time nor in space. Natural climate fluctuations and associated changes in the ocean currents have contributed to the inhomogeneity and is an important factor which will determine the pattern of future sea level rise. While research in the past years has focused on the global-mean trend and its attribution to the melting of glaciers and the thermal expansion of sea water under global warming, attention is shifting to the geographical pattern of sea level change. This is essential for coastal impact assessments, but has not been practical yet because ocean projections from current climate models widely diverge. The improvement of regional sea level prediction requires a better understanding of the underlying dynamical causes.

Description: Satellite images document a decrease in Arctic ice cover in summer by 40% during the past 30 years. However, responsible processes and possible consequences of this decrease are little understood. The joint Russian-German project „Laptev Sea Polynya“ is coordinated by IFM-GEOMAR and aims to ascertain the causes and consequences of climate change and its essential mechanisms in the Arctic. Now the project scientists revealed a changed water mass distribution in the Siberian Laptev Sea which might be of consequence for ice formation in the whole Arctic.

Description: Climate warming will affect the phytoplankton spring bloom. Experiments conducted at IFM-GEOMAR indicate, that bloom biomass of phytoplankton will become less, average cell size will become smaller, the biological carbon pump will be weakened and the timing of the bloom will be advanced a bit in a warming climate.

Description: The passive NW-African continental margin is characterized by several very large but infrequent landslides. Most of these landslides occurred during periods of low or rising sea level. Hence, the probability of future large-scale slope failures during the current sea level high stand is generally considered to be low. This interpretation is challenged by new observations during a recent research cruise to the Sahara Slide.

Description: The cold waters of the polar seas are naturally low in carbonate saturation. As uptake of anthropogenic CO2 continues to acidify the oceans worldwide, the Arctic Ocean will be the first to pass the chemical threshold where surface seawater becomes undersaturated, i.e. corrosive for unprotected shells and skeletons of calcifying organisms. While the overall impacts of ocean acidification on the Arctic ecosystems are still unknown, the predicted changes in seawater chemistry are expected to make it increasingly difficult for calcareous organisms to inhabit these regions.

Description: The Collaborative Research Centre 574: Fluids and Volatiles in Subduction Zones has the overarching goal to understand the role and fate of volatiles and fluids in the entire subduction system. The SONNE cruise SO-210 was the last major expedition of the 12-year programme.

Description: Carbon capture and storage (CCS), both on- and offshore, is expected to be an important technique to mitigate anthropogenic effects on global climate by isolating man-made carbon dioxide (CO2) in deep geological formations. In marine environments, however, the potential impacts of CO2 leakage, appropriate detection methods, and risk and pathways of atmospheric emissions are poorly defined. The natural CO2 gas seeps that occur in the relatively shallow waters off the coast of Panarea Island (Aeolian Islands, Italy) can be studied as a large-scale, real-world analogue of what might occur at a leaking offshore CCS site and what tools can be used to study it. The oceanographic survey PaCO2 was performed aboard R/V Urania from 27 July – 01 August 2011 (Naples – Naples). The project’s ship-time was funded by Eurofleets, with work being performed as a sub-project of the Seventh Framework Programme projects “ECO2” and “RISCS”, which provided subsidiary funding. Large amounts of data and samples were collected during the cruise which will be interpreted in the coming months, with preliminary results detailed here. Of particular importance was the discovery of much larger areas showing gas seepage than previously reported. Interdisciplinary measurements were performed at the Panarea seepage site. The international team of scientists onboard R/V Urania performed complementary sampling and measurements for biological, chemical, and physical parameters throughout the area. Together with the dedication of R/V Urania’s Captain and crew, and the eagerness and cooperation of the scientific crew, we were able to obtain excellent scientific results during this six-day cruise.

Description: Within the Jeddah Transect Project, a multidisciplinary marine sampling program has been performed on RV Poseidon (P408 cruise) offshore Saudi-Arabia (Red Sea). The sampling program involved three projects (http://www.ifm-geomar.de/index.php?id=jeddahtransectdisc&L=1), covering aspects of marine petrology, biogeochemistry, oceanography and biology.

Description: The DRIVE (Diurnal and RegIonal Variability of Halogen Emissions) campaign to the eastern tropical North Atlantic Ocean and the upwelling off Mauritania (NW Africa) was funded by the BMBF as part of the German SOLAS project SOPRAN II (Surface Ocean Processes in the Anthropocene; www.sopran.pangaea.de): The second leg of the 399th cruise of R/V Poseidon (P399/2) took place from 31 May to 17 June 2010 (Las Palmas-Mindelo (Cape Verde Islands) – Mauritanian upwelling – Las Palmas). It was followed by the transit leg 3 (P399/3) which took place from 18 June to 24 June 2010 (Las Palmas – Vigo (Spain)) with only one stop at ESTOC. Ten scientists from IFM-GEOMAR (Kiel), IfAM (U Kiel), IfBM (U Hamburg) and IUP (U Heidelberg) representing various SOPRAN II subprojects took part in the cruise which was the sixth of a series of German SOLAS cruises to the tropical North Atlantic Ocean. The major objective of P399/2 was to investigate the regional and diurnal atmospheric and oceanic variations of halogenated compounds in the eastern tropical North Atlantic Ocean with a special focus on the Mauritanian upwelling. The main working packages of P399/2 and P399/3 included measurements of - Atmospheric BrO and IO - Atmospheric halocarbons - Other atmospheric trace gases such as ozone, methane etc. - Aerosol composition - Vertical structure of the atmosphere - Dissolved halocarbons, nitrous oxide and carbon dioxide - CTD, dissolved nutrients, O2, and chlorophyll - Microstructure of the upper water column Besides an extensive underway measurement program of dissolved (halocarbons, N2O, CO2) and atmospheric (BrO, halocarbons, other trace gases, aerosol) compounds, six 24h stations were performed and 23 regular CTD stations with depth profiles covering the entire water column were occupied.

Description: Cruise SO210 with RV SONNE to the active continental margin off Chile was conducted by shiptime exchange with RV METEOR. Funds for mobilizing the research team were provided by the German Science Foundation (DFG) in conjunction with the Collaborative Research Centre (SFB) 574 of the University of Kiel. In the first years, the SFB 574 investigated the pathways and fluxes of volatiles through the erosive subduction zone off Central America. For comparison, the studies were extended to the accretionary margin off Central Chile. Cruise SO210 is the last cruise conducted in the framework of SFB 574 and based on investigations of previous SFB-cruises on the RVs VIDAL GORMAZ and JAMES COOK. The first leg of cruise SO210 was dedicated to long gravity coring for volcanic ash layers from the erruptive Southern Volcanic Zone (SVZ) of the Andes that were either deposited as fallouts onto the incoming Nazca Plate or transported down the slope and across the Chile Trench. Eight gravity cores of 12 m length were retrieved seaward of the Chile Channel on the outer rise of the Nazca Plate. The second goal for coring was the description and dating of previously mapped submarine landslides as well as retrieval of slide-related material for geo-technical experiments. As the deployment frame for long coring had to be removed on the second leg we continued coring for mass-wasting and geochemistry with short cores. Ten gravity cores of 3 or 6 m barrel length were retrieved upslope of slides, the glide plane and redeposited material downslope of the slide evacuation area. This sampling activity was supported by detailed acoustic surveys with Parasound and multibeam to remap critical areas for mass wasting in search for events, e.g. triggered by the recent Mw 8.8 Maule Earthquake, such as flanks of submarine canyons or previously detected submarine slides and to fill data gaps in the existing bathymetric data. The major activity of the entire cruise was dedicated to the search and detailed sampling of manifestations of fluid discharge activity on the Chilean forearc. A total of 11 deployments with the video sled OFOS and 12 dives by the ROV KIEL 6000 were conducted for ground-truthing of information which indicated possible seep activity and has been obtained during previous cruises to the Chilean forearc. In five working areas we found manifestations of fluid discharge. In these areas the survey was followed by an intense sampling of bottom water, sediments, carbonates, mega and meiofauna and the deployment of instrumentation on the seafloor. The goal of these deployments was to measure in situ seabed methane emission rates and associated fluxes of sulfide and major electron acceptors such as oxygen at seep sites along the Chilean margin and to understand its controls. This was accompanied by CTD casts to trace oxygen and the fate of methane discharge in the water column. Sediment cores obtained by multicorer or ROV were used for the geochemical characterization of the pore water and microbiological studies which include turnover rate measurements, molecular studies, flow through experiments and sampling of active sediments. Authigenic carbonates obtained by TV-Grab or ROV were sampled for fauna, biomarker studies and investigations to reconstruct the growth structures, calcification processes and fluid-pathway systematic. The sampling of sediments and carbonates recovered a unique fauna with 79 different taxa, several of them appear to be species new to science.

Description: Helena, Tim, Melanie und Tim, die sich in ihren Sommerferien langweilen, stolpern über einen Artikel über Sauerstoffminimumzonen. Sie beschließen, verschiedene Meereslebewesen vor Ort zu befragen, was es damit auf sich hat. Bei ihrer Recherche tauchen sie von der Meeresoberfläche bis 500 Meter unter dem Meer ...

Description: Port calls: Saßnitz

Description: Port calls: Stettin, Poland, 15.05.2011 – 16.05.2011

Description: Datum: 01.09.2011  Fahrtgebiet: Strander Bucht  Fahrtleiter: Dr. Jörg Bialas, IFM-GEOMAR

Description: Cruise SO-214 of R/V SONNE headed by IFM-GEOMAR served two legs of project NEMESYS, funded through the German Ministry of Education and Research (BMBF). Major partners of the project are Leibniz Institute of Marine Science (IFM-GEOMAR) and the Federal Institute of Geosciences and Natural Resources (BGR) Germany, as well as the Institute of Geological and Nuclear Sciences (GNS) and the Royal Netherlands Institute for Sea Research (NIOZ). NEMESYS aims to extend understanding and modelling of cold vents along the Hikurangi Margin (HM) off the east coast of the North Island of New Zealand. Since the first findings in the late 80´s several cruises have been dedicated to map and investigate the active seepage of Methane in this area. Results of these cruises headed by New Zealand and international scientists provided the database for the first joint German – New Zealand expedition SO-191 in 2007. During this cruise with R/V SONNE the HM was investigated within three legs comprising all marine geo-scientific disciplines. The major findings in geophysical, geological, geo-chemical, and biological research were published in a special issue by Marine Geology (Vol. 272, 2010). Nevertheless a lot of questions remained or were raised by the upcoming results. Still lateral continuation of feeder channels and a possible relation between internal structure, activity and tectonic regime of a seep site were not understood. The geological, geo-chemical and biological analysis has been related to the overall description and study of the seep sites along the margin. Detailed studies across a seep site and high-resolution sampling to study the internal variation of Methane production and the influences to chemistry and habitat have not been complete with the required intensity. These exemplary listed investigations together with an additional list of questions to seepage led to the follow-up project SO-214 NEMESYS, which was funded through the German Ministry of Education and Research (BMBF). Aim of the project NEMESYS is to confirm derived models of seep structures and to extend the existing database and knowledge by high-resolution sampling in all disciplines. Based on the findings of the SO-191 New Vents project Opouawe Bank and Omakere Ridge were identified as the areas with the highest interest for our additional studies. Opouawe Bank provides a high density of active seep sites with various expressions of feeder channels in seismic images. Omakere did provide the only seep sites that were found without feeder channels underneath. In between the Porangahau Ridge was selected as third target due to the indications of either gas or hydrate formation without active gas expulsion. Cruise SO-214 with R/V SONNE was split into two legs. The seismic part started on 09th March 2011 in the port of Wellington. Two 3D seismic cubes were acquired above active seep sites at Omakere and Opouawe Bank. A third cube at Porangahau Ridge could not be completed due to technical problems with the equipment and rough weather conditions. Intensive Parasound Profiling and extended 2D seismic with high resolution (up to 1.2 m migration grid) were undertaken. Many more feeder channels were identified than previously known from the SO-191 data, although not all of them terminate in a seafloor expression. The second leg left the port of Wellington on 6th April 2011 dedicated to intensive geological, geo-chemical and biological investigations. The major work was completed at Opouawe Bank. Based on images of the seismic data compilation North and South Tower seeps and seep site Takahe were chosen for the intensive sampling program. CTD and gravity cores were taken in dense spacing to investigate the local interaction of seepage and surrounding seafloor and water column. The water column showed limited stratification but seemed to be influenced from stormy weather. Biologic investigations showed limited variations compared with the SO-191 expedition, mainly in the distribution of fauna. The variety of amphipods seems to be a unique feature of the NZ seeps. The second leg suffered from bad weather conditions, which anticipated work during 100 hrs. out of scheduled 330 hrs. All meta data of the cruise are available through the IFM-GEOMAR Data Management Portal (https://portal.ifm-geomar.de/web/guest/home)

Description: Cruise WND-V was the fifth and final expedition of the West Nile Delta project carried out at IFM-GEOMAR with support from RWE-Dea. On this concluding cruise of the project, the two mud volcanoes North Alex and Giza were once again visited, this time using the Greek R/V AEGAEO. The primary purpose of the WND-V cruise was the recovery of instruments and observatories which had been deployed in or near the active centers of North Alex and Giza MVs over the past 30 months. In addition, complementary new data were acquired that were needed to better quantify the methane flux from the centers of both MVs. From 15 to 25 June 2010, the following activities were carried out: · recovery of 12 long-term Ocean-Bottom-Seismometers (OBS) at North Alex MV, which had been deployed during POSEIDON cruise P388 in 2009. · recovery of 4 instruments for measuring long-term pore pressure variations (piezometers) on the slope near North Alex MV, deployed during POSEIDON cruise P388 in 2009. · recovery of 6 instruments for measuring long-term chemical flux (CATmeters) at Giza and North Alex MV. · recovery of 1 instrument (OBMets) for measuring methane flux from the seafloor at North Alex MV. · recovery of 2 tiltmeters for measuring seafloor deformation at North Alex MV. · recovery of 2 long-term temperature observatories at Giza and North Alex MV. · CTD casts in the central area of North Alex MV · Imaging of bubble streams from the active center of North Alex using an SIMRAD EK60 sonar system. Although hampered by poor weather during the final days of the cruise the recovery operations were finished two days earlier than expected. Bathymetric data acquisition however, which had been part of the original schedule had to be cancelled due to bad weather as well as technical problems with the deep water sonar systems.

Description: The evolution from the Western Mediterranean Sea is inherently governed by (i) plate convergence between Nubia (Africa) / Eurasia and (ii) subduction related slab-roll back. Both processes are responsible for the surface features / topography of the Gulf of Cadiz / Gibraltar Arc / Alboran Sea / Rif / Betic domain and deep-seated features related to the consumption of African lithosphere. The project is part of the ESF-EUROCORES programme TOPO-EUROPE and is aiming to study the interrelation between convergence and major tectonic fault zones in the Gulf of Cadiz and the Alboran Sea (Trans-Alboran- Shear-Zone – Alboran Ridge) and Miocene subduction / deep-seated seismicity at 40-150 km depth. Monitoring networks with ocean bottom seismometers (OBS) and hydrophones (OBH) were installed first in the Alboran Sea (August 2009 to January 2010) and later in the Gulf of Cadiz (January 2010 to July 2010), providing for the first time local earthquake data collected on ocean bottom stations. First results suggest that the collected data are of every good quality to assess seismotectonics in both domains and yielding travel time data for unique tomographic images of the Gibraltar arc area and Alboran domain, providing seismic constraints on the structure of crust and mantle.

Description: RV Sonne cruise 206 started on the 31st of May in Caldera (Costa Rica) and ended there on the 18th of June 2010. An international group of 23 scientists and 2 guests from Costa Rica set out to perform geophysical, biogeochemical, and sedimentological investigations at and around a number of submarine cold seeps that are ubiquitous along this convergent continental margin. The cruise was predominantly conducted as a pre-site survey for IODP (proposal 633Full-2; Costa Rica Mounds) in order to fill existing gaps in the seismic record at two of the proposed drill locations. A 2D seismic survey was conducted running over the large-scale seamount subduction slide “Jaco Scarp” yielding a highly improved image of the structural pattern within the upper 1000 m of the sedimentary sequence. In addition, high-resolution 3D seismic data, roughly covering the uppermost 300 m, could be obtained in the Mound 11/12 area, which will allow for a detailed analysis of the internal structure of these mud volcano-like features and help to understand the complex relation to the upward directed material flow. Moreover, a total number of 36 sediment cores (TV-guided multicorer, gravity corer) were successfully retrieved from active cold seeps and submarine slides and a large number of sub-samples were taken for subsequent geochemical and microbiological analyses. Overall, all major tasks of this cruise could successfully be fulfilled and the results will help to further our understanding of mechanisms controlling fluid flow in the deep subsurface of active continental margins.

Description: The Kieler Wirkstoff-Zentrum KiWiZ (Centre for Marine Natural Products) at IFM-GEOMAR is investigating opportunities to use substances from microbial communties for medical and other applications. The new field of Marine Biotechnology is an emering area in Marine Sciences.

Description: Precise isotope analysis has developed to one of the most important tool in marine geochemistry. Accurate isotope fractionation is used for climate reconstructions for millions years back into the Earth’s history.

Description: The research project SO208 PLUMEFLUX (Propagation of Galápagos Plume Material in the Equatorial East Pacific) is funded by the German Ministry of Education and Research (BMBF) and focusses on seamounts on the Cocos Plate, formed at the East Pacific Rise but presently located off the coast of NW Costa Rica and Nicaragua (Leg 1), and on the Cocos-Nazca-Spreading Center(CNS; Leg 2). The studies conducted on cruise SO208 included multi-beam mapping, sediment echo sounding, hard rock sampling, as well as sedimentological and biological sampling. The major geological targets of Leg 1 were (1) to evaluate if the seamounts off northern Costa Rica and Nicaragua were formed by the Galápagos hotspot and thus to constrain the extent of influence by the Galápagos plume on the upper asthenosphere and lithosphere and (2) to constrain better the material input into the Central American subduction zone. Leg 2 aimed to sample profiles of the seafloor perpendicular to the CNS using the mobile drill Rockdrill 2 of the British Geological Survey, in order to reconstruct plume-ridge interaction in the past to complement morphological, petrological and geochemical studies carried out on previous cruises along the ridge axis (e.g. SO158). The integration of the results with existing data should contribute towards a better understanding of transport processes of plume material in the upper mantle and of the geodynamic evolution of the central East Pacific. The sedimentological studies carried out on both Legs of SO208 focussed on radiolarian assemblages. SO208 startet in Caldera/Costa Rica on July 15th, 2010, and ended in Guayaquil/Ecuador on August 29th, 2010. During Leg 1 nineteen seamounts on the Cocos Plate have been mapped and sampled. Within only 12 days at sea, a total of 41 stations(28 dredges, 2 TV grabs, and 11 multicorers) were carried out. Of these deployments, 23 recovered magmatic rocks, 15 volcaniclastics, and 13 Mn-Fe oxides. The samples comprise mainly pillow and sheet lavas, often with fresh glassy margins, and a wide spectrum of volcaniclastic rocks. Notably, we found several indications for explosive volcanic activity at water depths 〉 3,000 m. Due to a series of unfortunate circumstances beyond our control, the planned Rockdrill 2 deployment on Leg 2 had to be cancelled. Instead we mapped and collected samples via dredging from 60 localities along five profiles perpendicular to CNS. A total of 83 stations (76 dredges, 3 TVgrabs, and 4 multicorers) were carried out. Of these deployments, 59 recovered magmatic rocks, 3 volcaniclastics, 51 volcanic glass, and 6 Mn-Fe oxides, making this a successful cruise despite the Rockdrill problem. The first and most detailed profile (with 23 sampled localities) extended from the ridge axis to the north at ~92°W. The morphology shows alternating regions of abyssal ridges and valleys (possibly reflecting less plume input into the ridge) and thicker elevated bands commonly containing seamounts, some of which are tectonically deformed (possibly reflecting axial ridge type morphology and thus greater plume input into the ridge). The second profile was carried out at the shallowest part of the ridge axis, closest to the hotspot, just to the east of the 91° Transform Fault. The third profile extended 30 km north of the ridge (at ~89°30´W), where a formerly on-axis seamount has been split in half. We want to evaluate how far in the past the unique enriched geochemical anomaly associated with the seamount persisted in the past. Thirteen sites were successfully sampled along a fourth profile at 89°10’W, extending 35 km north and 35 km south of the CNS into crust up to 500,000 yrs old. This site was selected, because a major depleted geochemical anomaly exists at that location. A final short profile was carried out to the north and south and east (on the ridge axis) of a lava plateau at 88°20’W that represents an enriched anomaly along the ridge axis. The morphology of the area studied on Leg 2 strongly suggests that the intensity of interaction of the plume with the ridge has varied considerably over the last several hundred thousand years along the entire part of the ridge that we studied. Geochemical data should allow us to constrain better variations in plume-ridge interaction through time. Biological material was obtained successfully as macrofauna and as sediment samples containing meiofaunal organisms with the help of a geological chain bag dredge, sediment traps, a multicorer and a TV-grab. Macrofaunal organisms were recovered at 93 out of 124 stations, 37 stations revealed sediment samples. During the cruise, a total of 8,598 meiofaunal organisms were centrifuged out of about 45 kg of sediment and sorted to animal group. Foraminifera and Nematoda dominated the meiofauna, followed by Copepoda and at a lower abundance by Tardigrada, Kinorhyncha and Loricifera. We also discovered a highly diverse benthic macrofauna, mainly represented by Porifera, Bryozoa, Annelida, Brachiopoda and even a few monoplacophoran molluscs.

Description: El Niño-Southern Oscillation (ENSO) is the strongest natural climate phenomenon on timescales from months to a few years. Sucessfully modelling and subsequently forecasting ENSO is still a challenge although significant progess has been made during the past decades. IFM-GEOMAR scientists developed a new model which is currently being tested for ENSO applications.

Description: Marine scientists studying the seafloor always have to deal with the fact that the research vessel they are sailing with will be separated from the object they wish to study by several kilometers of water. Technological developments are helping IFM-GEOMAR scientists to overcome this problem and producing astounding results.

Description: Tectonic stresses lead to the deformation of the Earth’s crust and upper mantle. They are the driving force behind plate motion and mountain building, and they control earthquake distribution and intensity. These stresses can be measured from deformation microstructures of previously deeply buried rocks using paleo-piezometers. A new assessment of microstructural data from naturally deformed quartz-bearing rocks indicates that the mechanism of recrystallization fundamentally affects the piezometers. Our findings point out major inaccuracies of stress estimates published in the last 40 years, and it prepares the field for a new piezometer generation that will provide a significantly improved assessment of the stress states in lithospheric plates and plate boundaries.

Description: Changing environmental conditions, worldwide transport by commerical ships provide the basis for the increasing rates of marine invasions with substantial impact of marine ecosystems. Here we focus on the comb jelly Mnemiopsis leidyi one of the most prominent marine invaders. worldwide.

Description: Human-induced climate change is causing a warming of the surface ocean. Due to widely differing temperature sensitivities of key biological processes, this may have profound implications for marine food web interactions and the biogeochemical cycling of key elements such as carbon. Using a novel indoor-mesocosm approach, we show that rising sea surface temperature shifts the balance between photosynthetic production and respiratory consumption of organic carbon in a plankton community. This may weaken the ocean’s capacity to sequester atmospheric CO2, hence providing a positive feedback to anthropogenic climate change.

Description: Port calls: Saßnitz

Description: Kiel – Visby – Ventspils ‐ Kiel: 29. 05. – 21. 06. 2010 Cruise ALKOR 355 (AL‐355) was carried out within the framework of the EU FP‐7 project “HYPOX” (In situ monitoring of oxygen depletion in hypoxic ecosystems of coastal and open seas, and land‐locked water bodies). The scientific objectives focused on redox‐dependent nutrient and nitrogen cycles in the benthic boundary layer of the suboxic to anoxic Gotland Basin. The scientific party comprised of scientist from the IFM‐GEOMAR, Kiel (Germany). Main objectives were to study release rates and inventories of nutrients and nitrogen compounds under varying degrees of bottom water oxygenation in the anoxic to suboxic eastern Gotland Basin (central Baltic). Another goal was to quantify source/sink mechanisms of the benthic boundary layer for nitrogen species and nutrients under changing oxygen conditions to assess potential feedbacks on the upper mixed layer processes. In order to obtain these goal, we monitored the water column, sampled surface sediments and deployed several landers along a transect from oxygenated to suboxic and anoxic to sulfide benthic boundary layer conditions in the Latvian EEZ of the eastern Gotland Basin in a depth range from 49m to 235m.

Description: Es wird ein neuer Bodenwasserschöpfer von 4,2 l Inhalt beschrieben, der zusammen mit einer Probenahme des unmittelbar am Boden befindlichen Wassers eine sichere Temperaturmessung mit Kippthermometern ermöglicht. A new watersampler containing 4,2 1 is described. Together with water sampling of the bottom water a save measurement of the temperature with reversing thermometers is possible.

Description: Auf Grund langfristiger Registrierungen lassen sich die Strömungsverhältnisse an der Golfküste von Neapel als küstenparallele Grundströmung auffassen, der in periodischer oder nichtperiodischer Form Störungen überlagert sind. Es wird versucht, die EKMANSCHE Theorie des nichtstationären Triftstromes - unter Einbeziehung der horizontalen Reibung und einer Grundströmung - auf die küstenparallele Strömung zu erweitern. Im Gegensatz zu EKMAN, der bei einem konstant wirkenden Wind einen periodischen Massentransport erhält, strebt hier der Massentransport aperiodisch einem durch Reibung und Grundströmung bedingten Grenzwert zu. Außerdem erfolgt der Massentransport nicht senkrecht cum sole zur Windrichtung, sondern es ergeben sich in Abhängigkeit von Reibung und Grundstrom Winkel, die kleiner als 90° sind.

Description: Es wird ein neues Gerät beschrieben, mit dem im Gegenstromverfahren Wasser erzeugt wird, das mit wasserdampfgesättigter Luft bei einer wählbaren Temperatur im Gleichgewicht steht. Dieses Wasser dient als Absolutstandard bei der Sauerstoffbestimmung nach der Winklermethode. Die neu ermittelten Sättigungswerte von KLOTS und BENSON werden in einem Temperaturbereich zwischen 15° und 30° bestätigt. Die Standardabweichung des Sauerstoffgehalts von Simultanproben beträgt 0,005 ml 02/l und liegt damit innerhalb der Fehlergrenzen der angewandten chemischen Titrationsmethode. A new apparatus is described for equilibrating water with water vapor saturated air in a conter current system at defined temperatures. This water is taken as an absolute standard for the oxygen determination by the Winkler method. The new saturation values by KLOTS and BENSON could be confirmcd between 15 and 30° C. The standard dcviation of the oxygen content of replicate samples is 0.005 ml O2/l and is within the limits of error of the chemical titration method.

Description: Beschrieben wird ein Bodenberührungsschalter, der an Unterwassermeßgeräten befestigt werden kann und speziell für Geräte mit Frequenzmodulation und Einleiterkabel entwickelt wurde, z. B. die Bathysonde. A bottoming switch is described, which can be fastened to underwater instruments working with frequency modulation and single conductor cable, e.g. the so called Bathysonde.

Description: Es wird eine Methode zur einfachen, schnellen und genauen Bestimmung von Nitrat in Meer- und Trinkwasser beschrieben. Die nitrathaltige Wasserprobe wird unter Zusatz von Ammoniumchlorid und Ammoniak in einem Jones-Reduktor quantitativ zu Nitrit reduziert und das Nitrit photometrisch bestimmt. 0,05 µg-atom Nitrat-Stickstoff im Liter können noch sicher nachgewiesen werden. Die Standardabweichung der Bestimmung liegt bei einem Gehalt von 1,4 µg-atom N03- - N/L bei ∓ 0,016 µg-atom = ∓ 1,2%. Mit 6 Reduktoren können in der Stunde etwa 20 Wasserproben untersucht werden. A simple, rapid and accurate method for the determination of nitrate in sea and drinking water is described. Ammoniumchloride and ammonia solution are added to the water sample containing nitrate. The sample is quantitatively reduced to nitrite in a Jones reductor with cadmium amalgame. The nitrite is determinated photometrically. 0,05 µg-atom nitrate-nitrogen per liter can be detected surely. The standard cleviation at the 1,4 µg-atom level is ∓ 0,016 µg-atom N03--N / L = ∓ 1,2%. With 6 reductors about 20 samples can be analyzed within 1 hour.

Description: Im Ursprungsgebiet der Südäquatorialströmung findet man erhöhte Werte von Seston und Plankton. Die auf einer Fahrt mit H.A.M.S. DIAMANTINA im Juli und August 1961 gefundenen Daten sind für die Oberschicht in den Abb. 2-7 und für ausgewählte Vertikalserien in Abb. 9-13 zusammengestellt. Eine Deutung durch die hydrographischen Verhältnisse wird versucht. Tab. 1 und 2 enthalten Schicht-Mittelwerte für das untersuchte Gebiet. Some results are given from H.A.M.S. DIAMANTINA cruise 3/61 in July-August 1961. The data for the surface layer are presented in fig. 2-7, for selected casts in fig. 9-13, the values for definite levels are summarized in tables 1 and 2. Seston and microbiomass content is increased under the influence of the South Equatorial Current, and in shallow waters.

Description: Es werden Versuche mit zwei verschiedenartig aufgebauten Konzentrationszellen beschrieben, deren EMK auf Grund der Verwendung von Silber/Silberchlorid-Elektroden von der Chloridkonzentration im Elektrolyten abhängt. Die Arbeitsweise von Zellen mit Polyäthylen- und mit Ionenaustauschmembranen wird durch Meßreihen mit reinen NaCI-Lösungen und mit Seewasser verglichen. Es wird eine potentiometrische in-situ Anordnung beschrieben und ein Beispiel für eine schnelle Oberflächenaufnahme der Salzgehalts- und Temperaturverteilung gegeben. Experiments are discussed with two concentration cells of different construction. The emf of these cells depends on the concentration of chloride ions in solution because of the silver/silverchloride-electrodes used. The behaviour of cells with polyethylen membrans and with ion exchange membrans is compared by measurements with pure NaCl-solutions and with sea water. A potentiometric in-situ device is described and an example is given for a fast way of recording the surface distribution of salinity and temperature.

Description: Es wird gezeigt, daß man mit bekannten Routinemethoden der mathematischen Physik die Kenntnisse über Kinematik und Dynamik interner Wellen wesentlich gegenüber den aus der Theorie der Grenzflächenwellen bekannten Ergebnissen erweitern kann, wenn man mit einer exponentiellen Dichteverteilung rechnet. In den Abschnitten 1-3 werden bekannte Resultate zusammengestellt, Abschnitt 4 enthält eine Formel für die Wellenlänge interner Wellen (GI. 31). Die Energie interner Wellen (Abschnitt 5) erweist sich als erheblich größer als die der Grenzflächenwellen. In Abschnitt 7 werden Rechnungen über die Entstehung interner Wellen durch die Gezeitenkräfte, den Luftdruck und den Wind angegeben, und in Abschnitt 8 wird gezeigt, daß lineare inkompressible interne Wellen in der Tiefsee praktisch keine Dämpfung erfahren.

Description: Aus einem Material von je 1600 Seston- und Eiweißbestimmungen, die im Rahmen der deutschen Beteiligung am Polarfront-Programm des IGY gewonnen wurden, werden hier mittlere Tiefenverteilungswerte für diese beiden Komponenten der partikulären Substanz errechnet. Dabei ergeben sich Mittelwerte des Sestons für die Oberfläche zwischen 580 und 1810 µg/1 und für das Eiweiß von 28 bis 65 µg/1. Beide unterliegen in den obersten 50-100 m einer starken Reduktion (27-75%), die z. T. auf Akkumulation, z. T. auf Mineralisation zurückzuführen ist. Die Einzelwerte für große Tiefen (〉 1000 m) bewegen sich oft an der Grenze der Nachweisbarkeit; die Mittel betragen für das Südgebiet bei 1480 m Tiefe 100 bzw. 80 µg Seston und 6 bzw. 17 µg Eiweiß/l. Aus den Eiweißanalysen wird mit Hilfe tiefenvariabler Faktoren der Gehalt an lebender Substanz errechnet und daraus wieder durch Differenzbildung die mittleren Vlerte für den Detritusgehalt im hohen Ozean. Dieser beträgt an der Oberfläche 520 und 1190 µg/1 und sein Anteil im Spätwinter bzw. Spätsommer am Seston 76 und 79%. Ferner wird ein Vergleich zwischen Mittelwerten der gelösten organischen Substanz (n. Duursma) und denen der lebenden Substanz angestellt. Die Relation beider zu einander beträgt während der Sommeruntersuchungen 14.0 : 1 (51-100 m) bis 48.1 : 1 (401-500 m).

Description: Die Konstanz des zellulären ionalen Milieus, insbesondere die Aufrechterhaltung des ursprünglichen zellulären Kalium-Niveaus, ist eine wesentliche Vorbedingung für ein ungeschädigtes Überleben von Wirbellosen und Fischen in Ästuargewässern. The constancy of the cellular ionic medium, especially the maintenance of the original cellular potassium level, is an essential condition for the unharmed survival of invertebrates and fishes in estuarine waters.

Description: Zur Messung der Temperatur in Gebieten des Meeres mit starken Schwankungen der Schichtung wurde ein Meßverfahren entwickelt, das eine langzeitige Registrierung in einem verankerten Meßgerät erlaubt. Die Messung erfolgt über einen Thermistor in einer Wheatstone-Brücke, die Registrierung auf einem Fallbügelschreiber, die Steuerung über eine elektrische Uhr und Relaisschaltungen. Der Bereich umfaßt bei dem gebauten Gerät - 2° bis + 31° C, die maximal erreichbare Genauigkeit beträgt ± 0,1° C, als Betriebsdauer können bei einem Meßintervall von 5 Minuten ein Zeitraum von 50 Tagen, bei größeren Meßintervallen entsprechend höhere Zeiten erwartet werden. Eine Druckmessung zur Tiefenbestimmung und Eichungen der Anordnung erfolgen automatisch nach jeweils 21 Temperaturmessungen. Es werden das Meßgerät und die Laboratoriumstests sowie das Eichverfahren beschrieben, ferner werden Messungen mit dieser Methode in der Ostsee angegeben.

Description: Währcnd des in Norddeutschland ungewöhnlich kalten Winters 1962/63 trug die Elbe oberhalb von Hamburg mehrere Wochen lang eine 40-50 cm dicke Eisdecke, unterhalb der Stadt herrschte in dieser Zeit ständiges Eistreiben. Im Rahmen einer mehrjährigen mikrobiologischen Untersuchung wurde der Einfluß der anhaltenden Eisbedeckung auf das Bakterienleben im Strom studiert. Es zeigte sich, daß der Bakteriengehalt des Flullwassers wesentlich stärker als in normalen Wintern anstieg. Er belief sich besonders in dem Abschnitt oberhalb von Hamburg bei allen Stationen auf ein Mehrfaches der in der gesamten etwa 8 jährigen Untersuchungszeit vorher und nachher gewonnenen Maximalwerte. Die Ursache hierfür dürfte in erster Linie in dem Zusammentreffen von sehr geringer Wasserführung und anhaltend niedriger Temperatur liegen. Unter der Eisdecke kam es zu einer starken, vor allem von Mikroorganismen bewirkten Sauerstoffzehrung. Bedingt durch die anaeroben Verhältnisse erfolgte im Fluß eine lebhafte bakterielle Nitratreduktion (Denitrifikation). Diese wurde durch den kräftigen Rückgang des Nitratgehalts deutlich, der zunächst von einem starken Nitritanstieg begleitet wurde. Da die Nitratrcduktion über Nitrit bis zum freien Stickstoff führte, fand sich im Februar 1963 bei den meisten Stationen anorganisch gebundener Stickstoff fast nur noch in Form von Ammoniak. Laborversuche bestätigten, daß auch bei winterlichen Wassertemperaturen die Bakterientätigkeit noch stark genug ist, um den gesamten Sauerstoff in 02-gesättigtem Elbwasser innerhalb von 1 Woche zu verbrauchen. Das in der Elbe befindliche Nitrat kann dann ebenfalls in wenigen Tagen durch denitrifizierende Bakterien völlig über Nitrit zu freiem Stickstoff reduziert werden.

Description: Im Rahmen einer fischereibiologischen Fahrt von F.F.S. "Anton Dohrn" in das Gebiet der Faröer wurde im Januar 1964 eine eingehende Vermessung der Rosemary-Bank (φ = 59° 15' N, λ = 10° 10' W) durchgeführt.Als geringste Tiefe der isoliert gelegenen und teilweise steil aufragenden Kuppe wurden 325 m erlotet. Das annähernd kreisförmige Gipfelplateau besitzt Tiefen zwischen 400 und 700 m gegenüber 1400 - 2100 m in der weiteren Umgebung (Tafel 1 und 2). Der unsymmetrische Kegel weist nach W und S zu ein stärkeres Gefälle auf als an seinem E-Abhang. Am Fuß umgibt ihn als auffallendste morphologische Erscheinung eine ringförmige Mulde, deren Sohle 50 - 300 m tiefer liegt als der angrenzende Tiefseeboden. Im Anschluß an die Vermessung wurden außerdem zwei benachbarte Bänke abgelotet: Lousy-Bank (φ = 60° 25' N, λ = 12° 25' W) und Bill-Baileys-Bank (φ = 60° 35' N, λ = 10° 20' W). Die Tiefenverhältnisse der Gipfelregionen beider Bänke werden ebenfalls beschrieben (Tafel 3 und 4). In the scope of a fishery biological investigation made with F.R.S. "Anton Dohrn" in the area of the Faeroer Islands in January 1964 the topography of the Rosemary Bank (φ = 59° 15' N, λ = 10° 10' W) was exactly sounded. Lowest depth of the seamount is 325 m. The nearly circular summit plateau has depths between 400 and 700 m compared with soundings of 1400 to 2100 m in the environment (table 1 and 2). The cone which is not absolutely symmetrical is more declinated to the westside than to the east. As the most destinctive morphological phenomenon a ringshaped depression is surrounding the base of thc cone directly. lt is reaching down 50 - 300 m deeper than the neighboring deep sea bottom. In addition the depths of two further banks in the neighborhood of the Rosemary Bank have been sounded and their topography is described as follows: Lousy Bank (φ = 60° 25' N, λ = 12° 25' W) and Bill Baileys Bank (φ = 60° 35' N, λ = 10° 20' W). Bathymetric charts and sounding profiles are given in table 3 and 4.

Description: Es wurden Nordsee-Exemplare von Carcinides maenas aus Meerwasser von 30‰ Salzgehalt und Ostsee-Exemplare aus Backwasser von 15‰ Salzgehalt vergleichend untersucht. Die Atmungsintensität ganzer Ostsee-Exemplare übertrifft ebenso wie ihre Gewebeatmung die der Nordsee-Exemplare. Dabei ist die Stoffwechselintensität des Kiemengewebes der Ostsee-Individuen auch unabhängig von der Salzkonzentration des Atmungsmediums erhöht. Der Eiweiß- und der Hämocyaningehalt des Blutes der Ostsee-Exemplare sind im allgemeinen größer als der der Nordsee-Exemplare. Durch gekreuzte Anpassungen an Nordseewasser (30‰ S) und Ostseewasser (15‰ S) ließ sich zeigen, daß die Atmungsunterschiede und in zweiter Linie auch der Eiweiß-und der Hämocyaningehalt des Blutes von der Anpassung an den Salzgehalt des Außenmediums abhängig sind. Der Eiweiß- und Hämocyaningehalt des Blutes werden außerdem vom Ernährungszustand der Tiere beeinflußt. Die Ergebnisse machen es wahrscheinlich, daß die genannten physiologischen Unterschiede nicht genetisch fixiert sondern umgebungsbedingt sind. Comparative investigations were made on North Sea specimens of Carcinides maenas from normal sea water (30 per 1,000 S) and on Baltic Sea specimens from brackish water (15 per 1,000 S). The oxygen consumption of whole Baltic Sea specimens and their tissue respiration exceed considerably the corresponding values of North Sea specimens. The respiration of the gill tissue of brackish water specimens is also increased independently from salt concentration of the respiratory medium. The protein as well as the hemocyanin contents of the blood of Baltic-Sea specimens are normally higher than the corresponding values of North-Sea specimens. By alternating adaptation to North Sea Water (30 per 1,000 S) and Baltic Sea Water (15 per 1,000 S) it could be proved that the respiratory differences and secondly also the protein and hemocyanin contents of the blood are influenced by the adaptation to the salinity of the external medium. Besides the hemocyanin content of the blood is influenced by nutritional conditions of the animals. The results suggest that the physiological differences mentioned are environmentally induced rather than genetically fixed.

Description: Es wird über marin-vegetationskundliche Untersuchungen in der westlichen Ostsee (Kieler Bucht) berichtet. Für die Vegetationsaufnahme wurde eine Unterwasserfernsehanlage eingesetzt. Die Arbeit befaßt sich mit der großräumigen benthischen Vegetationsgliederung in der Kieler Bucht unterhalb der 5-m-Linie. Es werden die ökologischen Vegetationsbedingungen in diesem Gebiet diskutiert und die vegetationsphysiognomisch hervorstechenden Bewuchstypen dargestellt. A report on a survey of the marine vegetation in the western Baltic (Kiel Bay) is given. An underwater television set was employed for the vegetational mappings. This paper deals with the spatial distribution of the benthic vegetation in the Kiel Bay below the 5 m line. The ecological conditions for the vegetation in this area are discussed and the particularities governing the vegetational physiognomy are lined out.

Description: Die Hartbodenfauna der Schwentinemündung - ein Brackgewässer im westlichen Ostseebereich wurde untersucht. Der Salzgehalt nimmt in diesem Gewässer besonders in der Oberflächenschicht von der Einmündung in die Kieler Förde bis zu einem 2,4 km entfernt gelegenen Wehr kontinuierlich ab. Die Schwentinemündung läßt sich in 3 gegeneinander abgegrenzte Halinitätszonen gliedern. Jeder dieser Bereiche läßt sich durch eine spezifische Bewuchszone charakterisieren. Das größte Areal nimmt die α-mesohaline Zone ein. Sie wird von einer verarmten arktisch-borealen marin-euryhalinen Hartbodengemeinschaft (Mytilus edulis - Balanus crenatus-Biozönose) besiedelt. Die β-mesohaline Zone wird von einer südlich-borealen, marin-euryhalinen (brackischen) Hartbodengemeinschaft (Balanus improvisus - Membranipora crustulenta-Biozönose) bewohnt. Im α-Oligohalinikum breitet sich eine Grün- und Braunalgenzone aus, die von einer Mikrophytalgemeinschart bevölkert wird, welche sich zum größten Teil aus Brackwasserarten zusammensetzt.

Description: Im eulitoralen Bereich ebenso wie im Sublitoral wurden aus den jahreszeitlichen Veränderungen der Abundanz- und Dominanzverhältnisse der verschiedenen Fucus bewohnenden Tiergruppen Aspektfolgen erkannt. Es konnte die Eigenständigkeit der einzelnen Aspekte für die eulitorale Fucus-Zone und den Tiefen-Fucus gezeigt werden. Als Aspektbestimmend fielen im Eulitoral die Halacariden auf, während am sublitoralen Fucus die Nematoden besonders dedeutsam waren. Im eulitoralen Bereich stellte sich die Fucus besiedelnde Mikrofauna weitgehend als eine verarmte Fauna des Tiefenphytals dar, wies jedoch auch Arten auf, die in der eulitoralen Facus-Zone ihren optimalen Lebensbereich haben. Nur die Fucus-Bestände des Eulitorals erfüllen die Vorbedingungen eines Eigenbiotopes, für den Tiefen-Fucus ist dies im Ostseeraum nicht der Fall. Einteilung des charakteristischen Artenbestandes der eulitoralen Fucus-Zone in Charakterarten, dominierende Arten und Gäste gestattete das Hervorheben einer Art als Charakterart 1. Ordnung nicht, da keine stenöken Formen auftraten. Solche fanden sich auch unter den Epizoen nicht. Beziehungen zwischen Schleimabsonderung der Algen, Salinität und Ansiedlung von Bryozoen an bestimmten Teilen der Einzelpflanzen wurden bemerkt. Die Verbreitung einiger Amphipoden, Isopoden und Polychaeten an Fucus wurde kurz erörtert.

Description: Das Eulitoral des Roten Meeres ist trotz des extrem ariden Klimas, der hohen Insolation und des hohen Salzgehaltes von einer reichen Mikrofauna besiedelt. Die stärkste Artenentfaltung liegt im Bereich der sandsammelnden Rotalge Digenia simplex, die bisher noch nicht bekannte Lebensbedingungen im Eulitoral schafft. Die Sandregionen haben eine interstitielle Fauna, die in Zusammensetzung und Artenreichtum der der übrigen Meere ähnelt. Auch das subterrane Küstengrundwasser, das hier nur aus salzreichem Wasser besteht, enthält ebenfalls eine reiche Fauna. Die Anwurfzone (Wrack-Region) der Küste ist dagegen infolge der raschen Austrocknung des angespülten Pflanzenmaterials artenarm.

Description: In der Umgebung der Biologischen Station von Al Ghardaqa am Roten Meer wurden in verschiedenen Uferzonen freilebende Nematoden gesammelt. 49 verschiedene Arten wurden identifiziert, davon erwiesen sich 8 als neu. Die neuen Arten werden zusammen mit einer Anzahl bisher unzureichend bekannter Formen beschrieben.

Description: Der Strommesser registriert selbsttätig photographisch Stromrichtung und Stromgeschwindigkeit im Meere, und zwar bis zu einer Meßdauer von vier Wochen in Abständen von fünf Minuten. Er besitzt Eigenauftrieb und ist deshalb einfach zu verankern. Er kann bis Meßtiefen von 50 m ausgelegt werden. Dieser neue Strommesser nutzt die Vorzüge des Schaufelradstrommessers von H. Rauschelbach, der sich seit 25 Jahrerr in vielen hundert Auslegungen bewährt hat. Er vermeidet einen wesentlichen Nachteil dieses Gerätes, der besonders in gezeitenstromarmen Meeren wie der Ostsee ins Gewicht fällt, nämlich die hohe Anlaufgeschwindigkeit. Das neue Gerät ist ein Propellerstrommesser, der bei nur 2,5 cm/sec Stromgeschwindigkeit anspringt. Selbst in Bodennähe randlicher Meeresbuchten wie der Eckernförder Bucht konnten brauchbare Strommessungen über längere Zeiträume erzielt werden.

Description: Es wird untersucht, in welcher Weise Potentialmessungen an Galvanischen Zellen geeignet sind zur Ermittlung von Ionenkonzentrationen in Meerwasser. An Hand verschiedener für die Bestimmung von Chloridkonzentrationen geeigneter Zellanordnungen wird betrachtet, wie Änderungen der Konzentration, der Temperatur und des Druckes die Elektromotorische Kraft einer Galvanischen Kette beeinflussen. The application of potential mcasurements in the determination of ionic concentrations in seawater is investigated. Different types of galvanie eells suitable for the determination of chlorid ions are discussed together with changes of concentration, temperature and pressure ancl their effects on the electromotive force of the electrode systems.

Description: Die elektrische Leitfähigkeit des Blutes von Crangon crangon ist in einem Bereich von 3,6‰ bis 23-25‰ S größer als die des Außenmediums. Oberhalb von 25‰ S ist die elektrische Leitfähigkeit des Blutes geringer als die des Außenmediums. Die ionemegulatorische Leistung, gemessen an den Differenzen zwischen den Leitfähigkeiten des Innenmediums und denen des Außenmediums, ist bei an 5° C angepaßten Tieren größer als bei an 15° C angepaßten. Diese Ergebnisse stimmen mit früheren Gefrierpunksbestimmungen überein. Bei Temperaturen unter 5° C (deutlich bei 2° C) nimmt die ionenregulatorische Leistung wieder ab. Ganz ähnlich verhält sich die Krabbe Carci1111s maenas. Unterhalb von 28-29‰ S ist die Konzentration der Blutflüssigkeit (durch eine größere elektrische Leitfähigkeit) hypcrtonisch zum Außenmedium. Oberhalb von 29‰ S ist das Blut dagegen hypotonisch. Auch bei Carcinus erwies sich der „ionenregulatorische Apparat" bei an 5° C angepaßten Tieren in einem Bereich von 5‰ S bis 29‰ S leistungsfähiger als bei an 15° C angepaßten. Oberhalb von 29‰ S waren die Unterschiede zwischen kaltadaptierten und warmadaptierten nicht eindeutig.

Description: Es wird eine schnelle, bordtaugliche Methode zur polarographischen Bestimmung von in Meerwasser gelöstem Sauerstoff beschrieben. Die Messungen werden mit einer schnelltropfenden Quecksilberelektrode mit mechanisch gesteuerter Tropfenfrequenz ausgeführt. Es wird die Abhängigkeit des polarographischen Stromes von der Temperatur, dem Salzgehalt und dem Gehalt der Probe an gelöstem Sauerstoff bestimmt. Die Genauigkeit der Methode entspricht der einer routinemäßig ausgeführten Sauerstoffbestimmung nach WINKLER. Bei Reihenmessungen wird für eine Bestimmung etwa 1 Minute benötigt. A rapid and for the use on bord suitable method for the polarographic determination of dissolved oxygen in sea water is described. The measuremcnts are made with a rapidly dropping mercury electrode with mechanically controlled dropping frequency. The relation between polarographic current, temperature, salinity and oxygen content of the samples is determinated. The error of the method is equal to that of a routine WINKLER determination. In serie determinations it will take 1 minute to analyse a single sample.

Description: Mit Hilfe der vorhandenen Kenntnisse über Hydrographie und Plankton des Nordmeeres wird der Versuch gemacht, die Planktonbilanz dieses Meeres zu berechnen: überwiegt die Einfuhr aus dem Atlantik, die Ausfuhr nach der Barentssee und dem Arktischen Meer oder besteht ein Gleichgewicht? Die vorhandenen Daten reichen jedoch für eine vollständige Berechnung dieser Art nicht aus; lediglich die durch den Faröer-Shetland-Kanal hereintreibenden Planktonmengen können beziffert werden. Die jährlichen Transporte betragen in Tausend Tonnen Trockenmasse an Phytoplankton etwa 440, an Ciliaten 15, an Copepoden 470. Beim Phytoplankton überwiegt die Einfuhr in das Nordmeer, für das Zooplankton kann ein Urteil nicht abgegeben werden. Die einströmenden Algenmengen gelangen nicht in die zentralen Regionen des Nordmeeres und sind von geringer Bedeutung für dessen Vegetation. Das Zooplankton hingegen kann im Herbst zu einem großen Teil aus atlantischen Tieren bestehen.