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Larval survival and development of Carcinus maenas from Norway and Spain reared in a laboratory experiment

Larval and adult stages of marine species with complex life cycles often differ in thermal tolerance, with larvae typically showing narrower thermal tolerance limits. To assess how such stage-specific differences may influence species' range dynamics under climate change, we quantified larval performance of the European shore crab Carcinus maenas across an environmental temperature gradient. We measured larval survival rates (%) from hatching to metamorphosis to megalopa and the duration of development (days) at seven constant-temperature treatments (9-27 °C, in 3 °C increments). Data represent experimental observations of larval performance under laboratory conditions and are reported at the level of replicates by females of each population. Replication was performed on two levels: 5 * 10 larvae were reared per female, and 4 to 6 females were used per population. Larvae originated from berried females collected from populations at the southern and northern parts of the native European distribution (Vigo, Spain; Bergen and Trondheim, Norway). The data were collected during one reproductive period in 2022. We aimed to test the hypothesis that larvae from northern populations are more tolerant to low temperatures, while southern populations exhibit increased tolerance to high temperatures, which would facilitate poleward range expansion under warming conditions. Our results show that larvae from Spain displayed slightly higher survival rates to megalopa at warmer temperatures compared to those from northern populations. However, little variation in tolerance was observed between northern Spain and Norway, with low survival at the temperature extremes (9 °C and 27 °C). Notably, larvae from Norway exhibited faster development at low temperatures.

Growth rates and carbon and nitrogen contents of Carcinus maenas at metamorphosis to megalopa Norway and Spain reared in a laboratory experiment

Larvae of marine species with complex life cycles with wide latitudinal distribution ranges can differ not only in their thermal tolerance, but also in responses to temperature, such as growth rates and carbon or nitrogen accumulation. To assess population-specific growth rates, based on dry mass and carbon and nitrogen contents, we studied larval growth rates of the European shore crab Carcinus maenas across an environmental temperature gradient. We measured larval growth (day-1) from hatching to metamorphosis to megalopa at seven constant temperature treatments (9-27 °C, in 3 °C increments). Data represent experimental observations of larval dry mass, carbon and nitrogen contents under laboratory conditions and are reported at the level of replicates by females of each population. Replication was performed on two levels: 5 **10 larvae were reared per female, and 4 to 6 females were used per population. Larvae originated from berried females collected from populations at the southern and northern parts of the native European distribution (Vigo, Spain; Bergen and Trondheim, Norway). The data were collected during one reproductive period in 2022. Growth rates were low at low temperatures and increased with temperature, reaching a plateau at 21 °C. This increase in growth coincided with a reduction in duration of development, leading to similar body mass at metamorphosis across temperature treatments. Contrastingly, at the high temperature treatments 24°C and 27°C, reductions in duration of development did not coincide with increased growth rates, hence larvae metamorphosed with reduced body mass.

Carbonate chemistry from laboratory incubation experiments using water samples from the Elbe conducted in 2023

This dataset comprises key carbonate chemistry parameters measured and calculated in incubation experiments under different experimental conditions. pH, water temperature, and salinity were measured with a WTW multimeter (MultiLine® Multi 3630 IDS). Total alkalinity was determined by open-cell titration with an 888 Titrando (Metrohm). Saturation state of calcite and aragonite were calculated using phreeqpython, a Python wrapper of the PhreeqC engine (Vitens 2021) with pH, water temperature, total alkalinity, and major ions as major input, and phreeqc.dat as database for the thermodynamic data (Parkhurst and Appelo 2013). As the original Elbe water was supersaturated with carbon dioxide (CO2) with respect to the atmosphere, its partial pressure of CO2 (pCO2) level decreased during the incubation period with open flasks, which caused an adjustment of calcite saturation state (ΩC) for ambient air conditions. To adapt for the impact of pCO2 variations during the experiment, saturation state of calcite and aragonite was calculated assuming an equilibrium with an atmospheric pCO2 of 415 ppm (normalized ΩC and normalized aragonite sautration state ΩA). Since ion concentrations were measured for only a small number of samples, the ion concentrations of the remaining samples were reconstructed using stoichiometry based on the initial solution composition and total alkalinity. The concentrations of conservative ions (Na+, K+, Cl-, SO42-) were assumed remain constant, while ions related to carbonate precipitation (Ca2+, Mg2+) were calculated based on changes in measured alkalinity (see Figure 5 of the associated paper). Detailed analysis and calculation procedures are described in the Method section of the associated paper.

Light effects on the vertical positioning of the freshwater jellyfish (Craspedacusta sowerbii Lankester, 1880)

We experimentally manipulated the presence of light and light intensity (F = 36.7 μmol m⁻² s⁻¹; D = 0 μmol m⁻² s⁻¹; L = 4.8 μmol m⁻² s⁻¹; M = 21.4 μmol m⁻² s⁻¹) and tested their effects on the vertical positioning of the freshwater jellyfish (Craspedacusta sowerbii) medusae. For the experiments, approximately 100 C. sowerbii medusae were collected in August 2017 in two lakes (Haager Weiher and Leitner Weiher) in Bavaria, Germany. Testing was carried out at Seeon Limnological Station in close vicinity to the collection site. The experimental columns were 7.4 cm in diameter and 170 cm high and were marked with horizontal lines every 5 cm for visual position estimation. Four replicates run in parallel. One C. sowerbii medusa was used in each experimental column. Data cover three light treatments, each run twice: 1) 16:8 h full light (F)–dark (D) light intensity cycles (nF = 716, nD = 428), 2) 16:8 h full light (F)–full dark (D) light intensity cycles complemented with low (L) and medium (M) light intensities (nF = 96, nM = 96, nL = 48, nD = 288), and 3) altered light intensities in approximately 2-hour periods randomly among dark, low, medium, and full light intensities (nF = 96, nM = 76, nL = 72, nD = 336). Results show that light alone was sufficient to trigger a vertical position change of jellyfish towards the water surface, especially high light.

Data on the effect of temperature and trace metal exposure on early life stages of European flat oysters and Pacific oysters

Data collection of concentration dependent abnormal larval development of Crassostrea gigas during 24 h at 24°C and 48 h at 18°C for the trace metals copper (Cu), zinc (Zn), Cadmium (Cd) and lead (Pb). Data were collected via microscopic observation. Data collection of concentration dependent mortality within a 24 h period at 18°C and 24°C for the D- larvae stage of Ostrea edulis and C. gigas for Cu, Zn, Cd and Pb. Data were collected via microscopic observation. All data were collected from February to April 2024 at IFREMER Bouin (La plateforme mollusques marins de Bouin) in France. Data includes the measured environmental concentrations (MEC) of the summer Cu concentration in the German Bight from 1986 to 2021 (MUDAB database, https://geoportal.bafg.de/MUDABAnwendung/), including sampling points coordinates, year of sampling and Cu concentration. Additionally the Hazard quotient (HQ) is provided by dividing the MEC with the predicted no effect concentration (PNEC), defined as EC10 estimates from C. gigas embryos exposed for 48 h at 18°C and LC10 estimates from C. gigas larvae exposed for 24 h at 24°C, divided by an assessment factor (AF) of 5.

Observational dataset of behavioral response of three-spined sticklebacks to TNT exposure in a closed laboratory setup

Dumped munition in the German North Sea and Baltic Sea pose environmental risks as corrosion of the munition shells results in the leakage of the explosive 2,4,6-trinitroluene (TNT) into the marine environment. Uptake of TNT by marine biota and the associated negative effects on organisms are of major concern. This dataset reports behavioral responses of three-spined stickleback (Gasterosteus aculeatus) to environmentally relevant concentrations of TNT. Experimental sticklebacks were laboratory-bred and held in groups of 30 individuals in 60 L tanks in the fish facilities at the Thünen Institute of Fisheries Ecology in Bremerhaven. Parental sticklebacks originated from the Weser estuary (Luneplate, Bremerhaven, Germany, 53°28'36.9" N; 8°31'08.9" E) and were collected in April 2023. A total of 60 sticklebacks were tested in a controlled laboratory setup at the fish facilities at the Thünen Institute in Bremerhaven, containing two hideout zones formed by artificial plants. Each hideout was connected to an infusion system delivering either a TNT solution (100 µg/L) or control water into the zone currently occupied by the fish. Experimental trials were video-recorded to enable post hoc behavioral analysis. Behavioral metrics included the total time spent in the exposed hideout zone (s), latency to first leave the exposed hideout zone (s), and the number of crossings between hideout zones.

Laborversuche in einer Strömungsrinne mit skalierter Modelldüne (EbbSF)

Anhand von Experimenten im physikalischen Modell wurden durch Bodenformen verursachte Strömungs- und Turbulenzprozesse untersucht. Hierzu wurden Laborversuche in einer Strömungsumlaufrinne mit abstrahierten Modelldünen durchgeführt. Für die Erhebung eines umfangreichen Datensatzes zur Beschreibung des Strömungsfeldes über einer Bodenform wurde eine Modelldüne eingesetzt, deren Geometrie sich an in der Weser beobachteten Dünen mit sogenanntem Ebb Slip Face (EbbSF) orientiert. Die Dünenabmessungen und hydrodynamischen Größen wurden im Maßstab 1:10 nach Froude skaliert. Die Modelldüne wurde als zweidimensionale Einzeldüne eingebaut und einer unidirektionalen Strömung konstanter Geschwindigkeit und gleichbleibendem Wasserstand ausgesetzt. Durch die Verwendung von Riffelblech für die Herstellung der Modelldüne wurde die natürliche Oberflächenrauheit realer Dünen nicht nachgebildet. Für die Strömungsmessungen wurde im Bereich über und hinter dem Modellkörper eine enge Verteilung der Messpositionen gewählt, sodass ein umfassender Rohdatensatz mit hochfrequenten, akustischen Strömungsdaten bereitgestellt wird. Literatur: - Carstensen, C., Holzwarth, I. (2023): Flow and Turbulence over an Estuarine Dune – Large-Scale Flume Experiments. Die Küste. https://doi.org/10.18171/1.093103 - Bundesanstalt für Wasserbau (2021): FAUST. Teilprojekt E: Laboruntersuchungen BAW. FuE-Abschlussbericht B3955.02.04.70230. https://hdl.handle.net/20.500.11970/108336 Zitat für diesen Datensatz (Daten DOI): - Bundesanstalt für Wasserbau (2021): Laborversuche in einer Strömungsrinne mit skalierter Modelldüne (EbbSF) [Data set]. Bundesanstalt für Wasserbau. https://doi.org/10.48437/02.2021.K.9900.0001

Naturally occurring protoplasts in two Ulva spp. - Disc sizes from discs grown from protoplasts, after 35 days of germination, under culture conditions

Degradation in Ulva lacinulata and reproduction in Ulva compressa were observed and described for four weeks. The natural occurrence of protoplasts in both species was found. Protoplast yields were calculated each week for several weeks. At the beginning of the experiment, heterogeneity of the thallus was visible under the microscope. The diameter of the cells in the thalli that later became protoplasts were measured. A germination experiment was performed after protoplasts were collected. Germination rates were calculated based on the number of individuals visible by the naked eye at the end of the experiment. 2 % (U. lacinulata) and 4 % (U. compressa) of protoplasts germinated into two morphologies: unattached germlings and unattached discs. Because discs released gametes early in their development, their diameter was measured to estimate the gametes yields produced at the end of the experiment. During degradation of U. lacinulata, we found an increase in biomass after the first two weeks of the experiment. Fresh weight measurements were taken each week and relative growth rates were calculated. Our results provide the first evidence of the natural production of protoplasts in Ulva spp. and estimate that higher seeding yields can be obtained by natural protoplast production than direct gametogenesis.

Gas exchange data from Douglas fir juveniles during experimental drought and recovery

This dataset contains physiological measurements from a controlled laboratory experiment on juvenile Pseudotsuga menziesii (Douglas fir) conducted between June and August 2023 at the experimental greenhouse facility of the Karlsruhe Institute of Technology (KIT), Campus Alpin, Garmisch-Partenkirchen, southern Germany. The plant material originated from a commercial nursery in Franconia, Germany, and consisted of three-year-old trees maintained under uniform conditions prior to the experiment. The experiment aimed to assess the physiological responses of P. menziesii to progressive drought and subsequent recovery under controlled environmental conditions. Two drought treatments (mild and severe) were applied over a four-week period, followed by a re-watering phase. Air and soil temperature, relative humidity, vapor pressure deficit, molar flow, transpiration rate, net photosynthesis, conductance to water, and CO₂ exchange were recorded continuously using automated LI-COR gas exchange systems with separate branch (aboveground) and root (belowground) chambers. Each measurement is associated with a unique tree identifier, treatment level, and compartment. All timestamps are reported in Coordinated Universal Time (UTC). The dataset provides detailed observations suitable for examining drought stress responses and recovery dynamics in juvenile Pseudotsuga menziesii under controlled laboratory conditions.

Messsysteme für Großerzeugungs-Anlage, Teilvorhaben: Durchführung des Feldtests

Neue erneuerbare Erzeugungsmengen von mehr als 300 TWh werden bis 2030 zur Erreichung der Klimaziele und der Erhöhung der Gasunabhängigkeit durch Elektrifizierung in den Sektoren Wärme und Mobilität benötigt. Über ein intelligentes Messsystem können diese Anlagen sicher informationstechnisch angebunden und für die Netzintegration sowie Vermarktung gesteuert werden. Bislang ist dies für kleiner Erzeugungsanlagen möglich und beschrieben. Für Großerzeugungsanlagen werden wir dafür im Projekt MeGA ein Konzept entwickeln und bis zum Feldtest bringen. Mit unserem Projekt ermöglichen wir damit die Basis für die Nutzung des Cyber-Security-Konzepts des Smart Meter Gateways (SMGW) in zusätzlichen Anwendungsbereichen. Die Stadtwerke Pforzheim hat den Schwerpunkt ihrer Arbeiten in der praktischen Erprobung der Vorhabenziele. Konkret werden wir uns intensiv im Labortest und Feldversuch beteiligen.

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