API src

Found 8212 results.

Related terms

Ecosystem Engineering: Sediment entrainment and flocculation mediated by microbial produced extracellular polymeric substances (EPS)

Sediment erosion and transport is critical to the ecological and commercial health of aquatic habitats from watershed to sea. There is now a consensus that microorganisms inhabiting the system mediate the erosive response of natural sediments ('ecosystem engineers') along with physicochemical properties. The biological mechanism is through secretion of a microbial organic glue (EPS: extracellular polymeric substances) that enhances binding forces between sediment grains to impact sediment stability and post-entrainment flocculation. The proposed work will elucidate the functional capability of heterotrophic bacteria, cyanobacteria and eukaryotic microalgae for mediating freshwater sediments to influence sediment erosion and transport. The potential and relevance of natural biofilms to provide this important 'ecosystem service' will be investigated for different niches in a freshwater habitat. Thereby, variations of the EPS 'quality' and 'quantity' to influence cohesion within sediments and flocs will be related to shifts in biofilm composition, sediment characteristics (e.g. organic background) and varying abiotic conditions (e.g. light, hydrodynamic regime) in the water body. Thus, the proposed interdisciplinary work will contribute to a conceptual understanding of microbial sediment engineering that represents an important ecosystem function in freshwater habitats. The research has wide implications for the water framework directive and sediment management strategies.

Multibeam bathymetry processed data (Atlas Hydrosweep DS 3 echo sounder entire dataset) of RV POLARSTERN during cruise PS127, Atlantic Ocean

Multibeam data were collected during RV Polarstern cruise PS127 (2021-12-04 to 2022-01-02). Multibeam sonar system was Atlas Hydrographic Hydrosweep DS 3 multibeam echo sounder. Data are processed with Caris HIPS, including sound velocity correction with SV data from SVPs, CTDs, UCTDs and World Ocean Atlas 13 (https://doi.org/10.7289/v5f769gt), tidal correction with TPXO9_atlas_v5 (https://www.tpxo.net), and manual cleaning. The soundings are combined in daily files, the format is XYZ ASCII (<Lon> <Lat> <Depth in meters, positive up, relative to mean sea level>). Additional blockmedian grids have been computed with depth dependent cell size to visualize the data. These grids are not meant for scientific analysis or navigation, but for overview purposes only.

EG-Vogelschutzgebiete (1:5.000) in Schleswig-Holstein LfU

Die im Maßstab 1:5.000 vorliegenden Abgrenzungen stellen sinngemäße Übertragungen der offiziellen Abgrenzung der gemeldeten Gebiete (Meldung Deutschland an die EC) auf die Topografien der Deutschen Grundkarte 1:5.000 dar. Die Grenzverläufe im marinen Bereich der Nord- und Ostsee sind unverändert aus dem offiziellen Meldemaßstab 1:25.000 übernommen worden. In Schleswig-Holstein sind alle Vogelschutzgebiete und Gebiete gemeinschaftlicher Bedeutung (GGB oder englisch:SCI) nach nationalem Recht (NSG, LSG oder Europäische Vogelschutzgebiete, soweit nicht als NSG oder LSG ausgewiesen, gem. § 4 LNatSchG i. V. m. § 33 Abs. 1 Satz 1 BNatSchG i.V.m. § 24 Abs. 1 LNatSchG und den förmlich bekannt gemachten gebietsspezifischen Erhaltungszielen) zu Besonderen Schutzgebieten (SPA bzw. SAC) erklärt worden. Dementsprechend sind alle Vogelschutzgebiete und alle FFH- Gebiete in Schleswig-Holstein als Besonderes Schutzgebiet (SPA oder SAC) zu bezeichnen. Im Rahmen einer rechtlichen Sicherung der Einzel-Gebiete im Sinne § 32 Abs.2 und 3 BNatSchG i.V. mit § 23 Abs. 1 LNatSchG werden diese Abgrenzungen abschließend und rechtsverbindlich bearbeitet. Vogelschutzgebiet 0916-491 "Ramsar-Gebiet S-H Wattenmeer und angrenzende Küstengebiete": Im Norden reicht das Gebiet bis an das Hoheitsgebiet Dänemarks. Der Verlauf der Hoheitsgebietsgrenze im marinen Bereich (insbesondere nordwestlich von Sylt) ist zwischen beiden Staaten bislang noch nicht verbindlich kartografisch festgelegt. Stand: Dezember 2008 (letzte techn. Anpassung: 10.04.2012)

ADCP current measurements (1200 kHz) during RV SENCKENBERG cruise SE202208-2

Ocean velocities were collected by a Teledyne RDI 1200 kHz Workhorse Sentinel II ADCP that was mounted on RV SENCKENBERG during RV SENCKENBERG cruise SE202208-2. The transducer was located at 1.5 m below the water line. The instrument was operated in single-ping, broadband mode with bin size of 0.25 m and a blanking distance of 0.25 m. The velocity of the ship was calculated from position fixes obtained by the Global Positioning System (GPS) received at a Trimble SPS461 Modular GPS Heading Receiver. Heading was obtained both from the Trimble receiver and the internal ADCP gyro. Heading as well as pitch and roll data from ADCP's internal gyrocompass and the navigation data were used by the data acquisition software ViSea DAS (AquaVision®) internally to convert ADCP velocities into earth coordinates. Accuracy of the ADCP velocities mainly depends on the quality of the position fixes as well as Trimble receiver and internal ADCP heading data. Further errors stem from a misalignment of the transducer with RV SENCKENBERG's centerline.

Alkalinity concentrations from two benthic chambers and the ambient bottom water during an in-situ incubation experiment in July 2025

The dataset contains total alkalinity measurements from water samples collected during a 16-day in-situ incubation experiment in the Baltic Sea (2025-07-12 to 2025-07-29). Samples were collected using an automated glass-syringe sampler deployed within two benthic chambers of a Biogeochemical Observatory (BIGO, Sommer et al., 2009) at 54° 34.432' N, 10° 10.776' E, at 22 m water depth. In one chamber, 29 g of fine calcite powder were added to the bottom water. Seven samples per chamber and from the ambient bottom water were taken to monitor alkalinity changes resulting from calcite dissolution, providing a direct measure of the ocean alkalinity enhancement (OAE)

Methane concentration and diffusive flux in the Northern Sea off Heligoland in 2024

As part of the MOSES Project, in April 2023 methane measurements were started in the north-western part of the island Heligoland in the German Bight (North Sea). The objective was to complement the measurements of the Sternfahrten to identify the carbon cycle and its flow from the start of the Elbe river into the North Sea. Therefore, a Contros methane sensor for dissolved methane was deployed under water at about 10 to 12 meter depth (depending on the tide) close to the underwater observatory (UW-OBS) MarGate (54°11' N, 7°52' E), from the COSYNA Project. To ensure correct values latter was cleaned frequently from growing organisms by scientific divers. The present data contains the data from 2024, the second year running the sensors. Based on the concentrations of dissolved methane the methane emissions (diffusive flux) was calculated.

Nationalpark Schleswig-Holsteinisches Wattenmeer - Außengrenze des Nationalparks (LKN.SH - NPV)

Mit diesem Datensatz wird das Gebiet des Nationalparks „Schleswig-Holsteinisches Wattenmeer“ mit seiner Außengrenze bereitgestellt, ohne dabei die Lage der Schutzzonen 1 und 2 wiederzugeben. Der Verlauf der Nationalparkgrenze wird durch § 3 des Nationalparkgesetzes geregelt (Gesetz zum Schutz des schleswig-holsteinischen Wattenmeeres (Nationalparkgesetz – NPG vom 17. Dezember 1999; Gesetz- und Verordnungsblatt für Schleswig-Holstein S. 518), zuletzt geändert durch Art. 19 LVO v. 16.01.2019, GVOBl. S. 30 . Der Nationalpark wurde 1985 gegründet und 1999 erweitert. Er dient dem Schutz und der natürlichen Entwicklung des schleswig-holsteinischen Wattenmeeres und der Bewahrung seiner besonderen Eigenart. Die Gesamtheit der Natur in ihrer natürlichen Entwicklung mit allen Pflanzen, Tieren und Ökosystemen besitzt einen zu schützenden Eigenwert (§ 2 Abs. 1 Nationalparkgesetz). Um einen möglichst ungestörten Ablauf der Naturvorgänge zu gewährleisten wurde der Nationalpark in zwei Schutzzonen eingeteilt (Schutzzone 1 und Schutzzone 2), die mit verschiedenen Schutzbestimmungen versehen sind (Details zu den Schutzzonen siehe Objekt-ID: ED41FE5D-B260-4DE7-839E-21803829F5EA). Alle hier erwähnten Daten zum Nationalpark sind Auszüge aus: Rechtliche Gliederung des Nationalparks mit den angrenzenden Gebieten, Stand 12/2017 Kr. 11/2019 (Objekt-ID:5f2aeb4f-a5ec-4a0d-8a11-9f90fe4c7bee)

Multibeam bathymetry processed data (dataset compilation) of RV POLARSTERN & RV MARIA S. MERIAN during 44 cruises from 1984 to 2024, Fram Strait, Greenland Sea, Arctic Ocean

The Long-Term Ecological Research observatory HAUSGARTEN was established by the Alfred-Wegener-Institut Helmholtz-Zentrum für Polar- und Meeresforschung in the Fram Strait in summer 1999 to detect and track the impact of large-scale environmental changes on the marine ecosystem in the transition zone between the northern North Atlantic and the central Arctic Ocean. In this area, bathymetric data have been recorded with multibeam echosounders during 44 research expeditions on RV Polarstern and RV Maria S. Merian since 1984. From these data, a digital elevation model was generated and geostatistical analyses were performed to calculate geospatial derivatives and quantitative terrain descriptors for subsequent terrain analyses and habitat mapping. The dataset covers an area from 78°N to 81°N and 6°W to 12°E. To create the data product, archive data was used from seven different multibeam echosounders in various raw data formats. This data has been processed and cleaned with CARIS HIPS & SIPS, including sound velocity correction for datasets from 1999 and newer. Older datasets are calculated with a static sound velocity of 1500 m/s. Soundings where exported for gridding with Generic Mapping Tools (GMT) nearneighbor. The resulting Digital Elevation Model (DEM) is in the WGS84/Arctic Polar Stereographic (EPSG:3995) projection with a cell size of 100m x 100m. The hillshade was computed with a combination of slope and synthetic illumination with a vertical exaggeration of 10. Slope inclination was calculated with GDAL tool Slope with the formula of Zevenbergen and Thorne (1987) in degree. Terrain Ruggedness Index (TRI) was computed with the QGIS tool Ruggedness index following the approach of Riley et al. (1999) in meters. For the Bathymetric Position Indices (BPI), focal statistics have been calculated with the GRASS tool "r.neighbors" and the QGIS raster calculator following the concept of the Topographic Position Index (Weiss, 2001) with a circular reference area of 99 cells (broad) and 9 cells (fine). The additional coverage polygon layer gives and overview on the used datasets and their corresponding metadata. The map gives an overview on the LTER HAUSGARTEN area and the HAUSGARTEN 2024 DEM.

WMS MSRL:D10 Spülsaummonitoring (mv-lung)

Dieser WMS stellt die Ergebnisse die Daten des LUNG im Land Mecklenburg-Vorpommern fuer den Deskriptor 10 (Abfälle im Meer) fuer die MDI-DE dar.

Carbonate chemistry speciation of the 2023 KOSMOS Helgoland experiment on the effects of ocean alkalinity enhancement on pelagic foodwebs

This dataset contains carbonate chemistry speciation data of the 2023 KOSMOS mesocosm study on Helgoland, Germany. This study tested the effects of ocean alkalinity enhancement simulating lime additions on pelagic ecosystem functioning during a spring bloom. Carbonate chemistry speciation (fCO2, pHT, calcium carbonate saturation state) was generally calculated from measurements of total alkalinity (TA) and dissolved inorganic carbon (DIC) in depth-integrated water samples. There were 12 mesocosms in total and in 6 of them an alkalinity gradient of up to +1250 umol/kg was established in steps of 250 umol/kg. In the remaining 6 the same amount of alkalinity was added only to the upper portion of the mesocosms, resulting in twice the alkalinity increase there, before being mixed in after 48 hours. The two treatments simulated the immediate dilution of TA after ship deployment as well as a delayed one from a point source.

1 2 3 4 5 … 820 821 822