GPS raw data (control points and ground control points) from the Liguria Region, Borghetto Santo Spirito, Italy

Monitoring the impact of sea storms on coastal areas is fundamental to study beach evolution and the vulnerability of low-lying coasts to erosion and flooding. Modelling wave runup on a beach is possible, but it requires accurate topographic data and model tuning, that can be done comparing observed and modeled runup. In this study we collected aerial photos using an Unmanned Aerial Vehicle after two different swells on the same study area. We merged the point cloud obtained with photogrammetry with multibeam data, in order to obtain a complete beach topography. Then, on each set of rectified and georeferenced UAV orthophotos, we identified the maximum wave runup for both events recognizing the wet area left by the waves. We then used our topography and numerical models to simulate the wave runup and compare the model results to observed values during the two events. Our results highlight the potential of the methodology presented, which integrates UAV platforms, photogrammetry and Geographic Information Systems to provide faster and cheaper information on beach topography and geomorphology compared with traditional techniques without losing in accuracy. We use the results obtained from this technique as a topographic base for a model that calculates runup for the two swells. The observed and modeled runups are consistent, and open new directions for future research.

Seawater carbonate chemistry and processes during experiments with Emiliania huxleyi (PML B93/11A)

The formation of calcareous skeletons by marine planktonic organisms and their subsequent sinking to depth generates a continuous rain of calcium carbonate to the deep ocean and underlying sediments. This is important in regulating marine carbon cycling and ocean-atmosphere CO2 exchange. The present rise in atmospheric CO2 levels causes significant changes in surface ocean pH and carbonate chemistry. Such changes have been shown to slow down calcification in corals and coralline macroalgae, but the majority of marine calcification occurs in planktonic organisms. Here we report reduced calcite production at increased CO2 concentrations in monospecific cultures of two dominant marine calcifying phytoplankton species, the coccolithophorids Emiliania huxleyi and Gephyrocapsa oceanica . This was accompanied by an increased proportion of malformed coccoliths and incomplete coccospheres. Diminished calcification led to a reduction in the ratio of calcite precipitation to organic matter production. Similar results were obtained in incubations of natural plankton assemblages from the north Pacific ocean when exposed to experimentally elevated CO2 levels. We suggest that the progressive increase in atmospheric CO2 concentrations may therefore slow down the production of calcium carbonate in the surface ocean. As the process of calcification releases CO2 to the atmosphere, the response observed here could potentially act as a negative feedback on atmospheric CO2 levels.

Dominant zooplankton species and microelements in plankton obtained from White Sea surface waters

Despite the fact that plankton plays an important role in biogeochemical processes in oceans, data on its elemental composition, particularly in shelf seas of the Arctic Ocean, have thus far been insufficient. This communication, which is devoted to a comparative analysis of the elemental composition of plankton and bottom sediments in the White Sea, is part of the comprehensive investigation of the region that is occurring in line with the International Project ''Land-Ocean Interaction in the Russian Arctic'' (LOIRA).

Macrofauna abundance and sediment characteristics during R/V Senckenberg cruise west of Sylt in september 2010

The continuously influence of human impacts on the seafloor and benthic habitats demands the knowledge of clearly defined habitats to assess recent conditions and to monitor future changes. In this study, a benthic habitat dominated by sorted bedforms was mapped in 2010 using biological, sedimentological and acoustic data. This approach reveals the first interdisciplinary analysis of macrofauna communities in sorted bedforms in the German Bight. The study area covered 4 km², and was located ca. 3.5 km west of island of Sylt. Sorted bedforms formed as sinuous depressions with an east west orientation. Inside these depressions coarse sand covers the seafloor, while outside predominantly fine to medium sand was found. Based on the hydroacoustic data, two seafloor classes were identified. Acoustic class 1 was linked to coarse sand (type A) found inside these sorted bedforms, whereas acoustic class 2 was related to mainly fine to medium sands (type B). The two acoustic classes and sediment types corresponded with the macrofauna communities 1 and 2. The Aoinides paucibranchiata-Goniadella bobretzkii community on coarse sand and the Spiophanes bombyx - Magelona johnstonii community on fine sand. A transitional community 3 (Scoloplos armiger - Ophelia community), with species found in communities 1 and 2, could not be detected by hydroacoustic methods. This study showed the limits of the used acoustic methods, which were unable to detect insignificant differences in the fauna composition of sandy areas.

Physical properties, grain size distribution and clay mineralogy of ODP Leg 117 sites

The fabric of sediments recovered at sites drilled on the Indus Fan, Owen Ridge, and Oman margin during Ocean Drilling Program Leg 117 was examined by scanning electron microscopy to document changes that accompany sediment burial. Two sediment types were studied: (1) biogenic sediments consisting of a variety of marly nannofossil and nannofossil oozes and chalks and (2) terrigenous sediments consisting of fine-grained turbidites deposited in association with the Indus Fan. Biogenic sediments were examined with samples from the seafloor to depths of 306 m below seafloor (mbsf) on the Owen Ridge (Site 722) and 368 mbsf on the Oman margin (Sites 723 and 728). Over these depth ranges the biogenic sediments are characterized by a random arrangement of microfossils and display little chemical diagenetic alteration. The microfossils are dispersed within a fine-grained matrix that is predominantly microcrystalline carbonate particles on the Owen Ridge and clay and organic matter on the Oman margin. Sediments with abundant siliceous microfossils display distinct, open fabrics with high porosity. Porosity reduction resulting from gravitational compaction appears to be the primary process affecting fabric change in the biogenic sediment sections. Fabric of illite-rich clayey silts and silty claystones from the Indus Fan (Site 720) and Owen Ridge (Sites 722 and 731) was examined for a composite section extending from 45 to 985 mbsf. In this section fabric of the fine-grained turbidites changes from one with small flocculated clay domains, random particle arrangement, and high porosity to a fabric with larger domains, strong preferred particle orientation roughly parallel to bedding, and lower porosity. These changes are accomplished by a growth in domain size, primarily through increasing face-to-face contacts, and by particle reorientation which is characterized by a sharp increase in alignment with bedding between 200 and 400 mbsf. Despite extensive particle reorientation, flocculated clay fabric persists in the deepest samples examined, particularly adjacent to silt grains, and the sediments lack fissility. Fabric changes over the 45-985 mbsf interval occur in response to gravitational compaction. Porosity reduction and development of preferred particle orientation in the Indus Fan and Owen Ridge sections occur at greater depths than outlined in previous fabric models for terrigenous sediments as a consequence of a greater abundance of silt and a greater abundance of illite and chlorite clays.