Hydroacoustic Seafloor Monitoring and Hydrodynamics West of Sylt and Northeast of Helgoland (German Bight) Cruise No. AL519-1 23.01.2019 – 07.02.2019 Kiel (Germany) – Bremerhaven (Germany) STENCIL

The cruise AL519-1 was executed in the frame of BMBF research project STENCIL (strategies and tools for environment-friendly shore nourishments as climate change impact low-regret measures). It is a jointproject between the AlfredWegenerInstitutefor Polar and Marine Researchin List on Sylt, RWTH Aachen University, Forschungszentrum Küste in Hannover, Leichtweiß-Institute für Wasserbau in Braunschweig and Ludwig-Franzius-Institute in Hannover. The project aims tomakethefirst step of a longer term vision towards an ICZM (integrated coastal zone management) and EAM(Ecosystem Approach to Management)for shore nourishments. Thefocus isthe German WaddenSea with the island of Sylt asthepilot site. During the cruise, several hydroacoustic devices were deployed within three different survey areas. The measurements took place in the contextof a monitoring program,which investigates the hydrodynamic and morphodynamic conditions in the area of the largest sand mining site in the German Bight.The aim is to figure outwhich impactson marine habitats occurbecause of the human activities. Within the excavationpits(depth of max. 20 m),only a very slow refill with muddy material is noticeable while the habitats in this area are permanently changed. However, the marine habitat in immediate vicinity seems unaffected

Impact of marine sand extraction on benthic communities west off Sylt (SE North Sea)

Ongoing erosion at coasts, beaches and dunes accompanied by a climate change-induced sea-level rise requires extensive protection measures. At the Island of Sylt (SE North Sea) beach nourishments were conducted for almost 50 years to protect the exposed western coast against erosion. Since 1984, the materials for the sand replenishments were dredged from an offshore excavation site approx. 7 km west off Sylt in the German Bight. In this study, we investigate the long-term effects of sand extraction on the local geomorphology, the associated benthic habitats and fauna. Hydroacoustic surveys and grab sampling revealed that after more than 35 years changes in bathymetry (with dredging pits of down to ~15 m below sea floor) and also changes in habitat characteristics are still present. Additionally, the sediment and benthic faunal compositions have changed. A comparison between dredged areas and undisturbed seafloor revealed significant differences in mud content (increasing), the number of individuals and species of macrozoobenthic organisms (decreasing). This indicates that the benthic communities in the dredging areas are in a persistent successional stage. Mud-loving species (e. g. Notomastus latericeus and Kurtiella bidentate) profit from the changed habitats, however sand-preferring organisms (e.g. Pisione remota and Aonides paucibranchiata) largely disappeared. Because of the slow backfill rates, we conclude that a complete backfill of the deep dredging pits is likely to take centuries. The same is expected to apply for the regeneration of the benthic communities. However, since rather coarse-to-medium sand was removed from this area and re-accumulation of this Pleistocene material is not possible because of weak transport rates, a re-establishment of benthic communities that prefer coarser sand seems to be unlikely. Since benthic communities are strongly linked to the habitat characteristics, habitat mapping using hydroacoustic techniques is an efficient and cost-effective measure to monitor the state of regeneration in this study site

Soziale Ungleichheit in der gesundheitlichen Versorgung: Argumente gegen die Überbetonung des Gesundheitsverhaltens

"Gegenwärtig wird oft hervorgehoben, wie wichtig Gesundheitsverhalten und Eigenverantwortung sind. Eine Verbesserung des Gesundheitsverhaltens in den unteren Statusgruppen würde ohne Frage zu einer erheblichen Verringerung der gesundheitlichen Ungleichheit führen. Das Gesundheitsverhalten lässt sich mit Appellen an die Verantwortung für die eigene Gesundheit häufig jedoch kaum beeinflussen. Das Gesundheitsverhalten basiert zudem oft nicht nur auf freien Entscheidungen, sondern es wird maßgeblich geprägt durch die Lebensumstände. Ohne Berücksichtigung dieser komplexen Ursachen des Gesundheitsverhaltens besteht somit die Gefahr, dass dem 'Opfer die Schuld zugeschoben wird' (blaming the victim). Um die Ursachen von Krankheit (und damit auch die Ansätze von Gesundheitsförderung und Prävention) verstehen zu können, ist die Unterscheidung zwischen 'Verhalten' und 'Verhältnisse' nach wie vor hilfreich. In der jetzigen Diskussion erscheint es vor allem wichtig, (wieder) an die Wichtigkeit der 'Verhältnisse' zu erinnern. Hierfür sind m. E. zwei Problembereiche besonders gut geeignet. Der erste trägt die Überschrift 'Environmental Justice'; hier steht die soziale Ungleichheit bei Lärm, Luftverschmutzung etc. im Mittelpunkt. Der zweite Problembereich lässt sich mit 'Soziale Ungleichheit in der gesundheitlichen Versorgung' umschreiben. Inzwischen mehren sich auch in Deutschland die empirischen Belege dafür, dass Probleme der gesundheitlichen Versorgung vor allem bei den unteren Statusgruppen vorhanden sind. Da diese Gruppen zumeist eine erhöhte Mortalität und Morbidität aufweisen, ist bei ihnen auch der Bedarf an Gesundheitsversorgung besonders groß. Das Angebot an gesundheitlicher Versorgung mag vorhanden sein, aber offenbar entspricht die Inanspruchnahme nicht immer diesem erhöhten Bedarf. Etwas präziser formuliert lautet die Frage demnach, ob diese 'Unter-Inanspruchnahme' vor allem der Eigenverantwortung des Versicherten oder aber der Verantwortung des Gesundheitssystems zuzuordnen ist. Wie die gegenwärtige Gesundheitsreform-Diskussion zeigt, wird zurzeit versucht, die Verantwortung des Gesundheitssystems immer stärker zu verdrängen." (Autorenreferat

Excess direct medical costs of severe obesity by socioeconomic status in German adults

Objective: Excess direct medical costs of severe obesity are by far higher than of moderate obesity. At the same time, severely obese adults with low socioeconomic status (SES) may be expected to have higher excess costs than those with higher SES, e.g. due to more comorbidities. This study compares excess costs of severe obesity among German adults across different SES groups

2. Wochenbericht AL519-1

Wochenbericht AL519-1 (28.01.-03.02.2019) [Alkor

Multiannual Seafloor Dynamics around a Subtidal Rocky Reef Habitat in the North Sea

Rocky reefs provide complex structures in the otherwise largely sand-dominated coastal North Sea. Therefore, these reefs are highly important natural habitats for the functioning of coastal ecosystems, as they provide shelter, refuge and nursery grounds for various mobile and sessile species. In the North Sea, the spatial distribution of these habitats has been intensively investigated over recent years. However, these studies generally provide static accounts of the current state of these reef systems, but limited data exist on the temporal variations in sediment dynamics at and around natural rocky reefs. In this study, we provide observations from a multiannual time series of hydroacoustic seafloor surveys conducted at an isolated rocky reef in the North Sea. We use multibeam bathymetry and side-scan sonar backscatter data in combination with video observations, sediment sampling, and sub-bottom profiler data to assess the long-term variations of the rocky reef system. The reef is located in water depths between 11 and 17 m with an areal extent of ~0.5 km2 and is surrounded by mobile sands. The topography of the rocky reef appears to create a distinct hydrodynamic system that permits mobile sands to settle or move into bathymetrical deeper parts of the reef. Our results suggest a very dynamic system surrounding the reef with large scale scouring, sediment reworking and transport, while the shallower central part of the reef remains stable over time. We demonstrate the importance of hydrodynamics and current scouring around reefs for the local variability in seafloor properties over time. These small-scale dynamics are likewise reflected in the spatial distribution of sessile species, which are less abundant in proximity to mobile sands. The hydroacoustic mapping and monitoring of seafloor dynamics at higher spatial and temporal resolutions presents an important future direction in the study of valuable coastal habitats

1. Wochenbericht AL519-1

Wochenbericht AL519-1 (23.-27.01.2019) [Alkor

Persistent effects of sand extraction on habitats and associated benthic communities in the German Bight

Sea-level rise demands for protection measures of endangered coastlines crucial for the local population. At the island of Sylt in the SE North Sea, shoreline erosion is compensated by replenishment with sand dredged from an offshore extraction site. We studied the long-term effects of sand extraction on bathymetry, geomorphology, habitats and benthic fauna. Sand extraction created dredging holes about 1 km in diameter and up to 20 m below the ambient seafloor level. Directly after dredging the superficial sediment layer, inside the pits was dominated by coarse sand and stones. Hydroacoustic surveys revealed only minor changes of bathymetry > 35 years after sand extraction. Obviously, backfill of the dredging pits was very slow, at a rate of a few millimeters per year, presumably resulting from low ambient sediment availability and relatively calm hydrodynamic conditions despite high wave energy during storms. Thus, a complete backfill of the deep extraction sites is likely to take centuries in this area. Hydroacoustic surveys and ground truthing showed that the backfilled material is mainly very fine sand and mud, turning the previously coarse sand surface into a muddy habitat. Accordingly, grab samples revealed significant differences in macrozoobenthos community composition, abundance and species density between recently dredged areas ( 10 years ago) and undisturbed sites (control sites). Overall, dredging turned the original association of sand-dwelling species into a muddy sediment association. Since re-establishment of disturbed benthic communities depends on previous re-establishment of habitat characteristics, the low sedimentation rates indicate that a return to a pre-dredging habitat type with its former benthic community and habitat characteristics is unlikely. Since coarse sand is virtually immobile in this area, a regeneration towards pre-dredging conditions is also unlikely without human interference (e.g., mitigation measures like depositing coarse material on the seafloor to restore the sessile epifauna)