ALBERT

Description: General characteristics of macrobenthos of muddy sediments of the subtidal (19-24 m) zone in the Nha Trang Bay (South Vietnam) were described based on the survey performed in April-May 2002. The mean abundance of organisms was 637 ind/m**2 and the mean biomass was 2.3 g/m**2. Sixty-seven macrobenthic species were found during the study. The main structural features of the macrobenthos were high species diversity, low species recurrence, and high evenness of species structure with the absence of clearly manifested dominants. The number of species encountered regularly increased with the increase in the total area sampled from 210 to 5000 cm**2, though the relation did not reach saturation. Similarities and differences between the macrobenthos structures in the Nha Trang Bay and those in some tropical and boreal soft-bottom communities are discussed.

Description: In situ effects of ocean acidification are increasingly studied at submarine CO2 vents. Here we present a preliminary investigation into the water chemistry and biology of cool temperate CO2 vents near Whakaari–White Island, New Zealand. Water samples were collected inside three vent shafts, within vents at a distance of 2 m from the shaft and at control sites. Vent samples contained both seawater pH on the total scale (pHT) and carbonate saturation states that were severely reduced, creating conditions as predicted for beyond the year 2100. Vent samples showed lower salinities, higher temperatures and greater nutrient concentrations. Sulfide levels were elevated and mercury levels were at concentrations considered toxic at all vent and control sites, but stable organic and inorganic ligands were present, as deduced from Cu speciation data, potentially mediating harmful effects on local organisms. The biological investigations focused on phytoplankton, zooplankton and macroalgae. Interestingly, we found lower abundances but higher diversity of phytoplankton and zooplankton at sites in the direct vicinity of Whakaari. Follow-up studies will need a combination of methods and approaches to attribute observations to specific drivers. The Whakaari vents represent a unique ecosystem with considerable biogeochemical complexity, which, like many other vent systems globally, require care in their use as a model of 'future oceans'.

Description: Abstract

Description: This data publication provides a collection of ground-motion simulation output for potential future earthquakes in the Rhine Graben area, Germany. Such data can be used as input for other engineering calculations, such as dynamic response history analysis. The earthquake sources used for the simulation consist of a stochastic catalog. They were generated using the German national seismic hazard model, the event-set calculator in the OpenQuake engine (Pagani et al., 2014), and considering both areal seismic source and known tectonic faults in the area as seismic sources in the analyses (branch C in Grünthal et al.,2018). The generated events represent a possible realization of the seismicity in the area within 10,000 years with peak ground accelerations greater than 0.02g. To build the simulation database, ground-motion simulations are performed using these potential future earthquakes from stochastic catalog and adopting the simulation method of Graves and Pitarka (2010, 2015) implemented in the Southern California Earthquake Center (SCEC) broadband platform (BBP), which is tailored for use in the Rhine Graben, as discussed in Razafindrakoto et al. (2021). Here, the approach used to simulate the ground-motion is only briefly discussed; a more accurate description is given in Razafindrakoto et al. (2021), discussing the calibration and validation of ground-motion in the Rhine Graben area. Accordingly, the provided data consists of a simulation output of 284 scenario earthquakes at 76 virtual stations in the Rhine Graben area. The files provided here include the earthquake source, station information, and the simulation results in terms of time histories for individual simulation in one zip file, and a flatfile that combines various intensity measures for all sources and stations.