RBINS Open Access Library

Iron and sulfur cycling in the cGENIE.muffin Earth system model (v0.9.21): The coupled biogeochemical cycles of iron and sulfur are central to the long-term biogeochemical evolution of Earth’s oceans. For instance, before the development of a persistently oxygenated deep ocean, the ocean interior likely alternated between states buffered by reduced sulfur (“euxinic”) and buffered by reduced iron (“ferruginous”), with important implications for the cycles and hence bioavailability of dissolved iron (and phosphate). Even after atmospheric oxygen concentrations rose to modern-like values, the ocean episodically continued to develop regions of euxinic or ferruginous conditions, such as those associated with past key intervals of organic carbon deposition (e.g. during the Cretaceous)and extinction events (e.g. at the Permian–Triassic boundary). A better understanding of the cycling of iron and sulfur in an anoxic ocean, how geochemical patterns in the ocean relate to the available spatially heterogeneous geological observations, and quantification of the feedback strengths between nutrient cycling, biological productivity, and ocean redox requires a spatially resolved representation of ocean circulation together with an extended set of (bio)geochemical reactions. Here, we extend the “muffin” release of the intermediate complexity Earth system model cGENIE to now include an anoxic iron and sulfur cycle (expanding the existing oxic iron and sulfur cycles), enabling the model to simulate ferruginous and euxinic redox states as well as the precipitation of reduced iron and sulfur minerals (pyrite, siderite, greenalite) and attendant iron and sulfur isotope signatures, which we describe in full. Because tests against present-day (oxic) ocean iron cycling exercises only a small part of the new code, we use an idealized ocean configuration to explore model sensitivity across a selection of key parameters. We also present the spatial patterns of concentrations and d56Fe and d34S isotope signatures of both dissolved and solid-phase Fe and S species in an anoxic ocean as an example application. Our sensitivity analyses show that the first-order results of the model are relatively robust against the choice of kinetic parameter values within the Fe–S system and that simulated concentrations and reaction rates are comparable to those observed in process analogues for ancient oceans (i.e. anoxic lakes). Future model developments will address sedimentary recycling and benthic iron fluxes back to the water column, together with the coupling of nutrient (in particular phosphate) cycling to the iron cycle.
Located in Library / RBINS Staff Publications 2021
A series of two Workshops to develop a suite of management options to reduce the impacts of bottom fishing on seabed habitats and undertake analysis of the trade-offs between overall benefit to seabed habitats and loss of fisheries revenue (WKTRADE3): WKTRADE3 developed methods and data flows that allow the assessment of seabed abrasion, economic value, weight of landings and impact on the seabed of mobile bottom-contacting gears in European waters by MSFD broad habitat type and métier. This report provides regional-specific assessments of pressure and impact of bottom-contacting fishing gears on the seabed and of trade-offs between fisheries and seafloor habitat protection. We also present an analysis of spatial and temporal variation in core fishing grounds, and review and evaluate any potential consequences to the ecosystem that could arise, if greater areas of seabed are left undisturbed by bottom fishing. An attempt was made to disaggregate variable costs from the STECF Annual Economic Report out on VMS data. The assessment covers four MSFD (sub)regions, 22 sub-divisions and four countries from Mediterranean and Black Sea. It is spanning from Norway and Finland in the North to Bulgaria in the south. For all areas, the surface abrasion data were avail-able for at least one year. For the Greater North Sea and Baltic Sea, it was possible to perform a complete analysis, while in the other regions data availability was more limited and it was not possible to assess the seabed impact. The impact of mobile bottom-contacting gears (MBCG) on seabed biota was assessed using two different methods and the percentage unfished c-squares was used as an indicator of fishing pressure. The average fishing intensity varies widely between habitat types and regions. Landings per swept area, and landings per unit impact also vary be-tween métiers by an order of magnitude. Effort reductions resulted in different responses between the two impact indicators and the fishing pressure indicator. For PD, the reduction of effort resulted in proportional reductions between benthic impact and fisheries value. For the two other indicators, L1 and percentage area unfished, the relationship between the weight/value and the indicators was not linear, meaning that larger improvements in the indicators could be obtained at small decreases in fisheries landings. There are many other direct and indirect benefits to eco-system and ecosystem services that could result from a reduction in MBCG, but currently the methods and data are not available to quantify these at the required spatial scale. Collectively, ICES expert groups produce many valuable reports each year. Some of these are very long (up to 1000 pp.). As much of the target audience will not have time to read the whole of each document, it is imperative that reports start with a clear, succinct, and factual executive summary that presents the key issues addressed in the main report.
Located in Library / RBINS Staff Publications 2021
Subtidal Natural Hard Substrate Quantitative Habitat Mapping: Interlinking Underwater Acoustics and Optical Imagery with Machine Learning: Subtidal natural hard substrates (SNHS) promote occupancy by rich benthic communities that provide irreplaceable and fundamental ecosystem functions, representing a global priority target for nature conservation and recognised in most European environmental legislation. However, scientifically validated methodologies for their quantitative spatial demarcation, including information on species occupancy and fine-scale environmental drivers (e.g., the effect of stone size on colonisation) are rare. This is, however, crucial information for sound ecological management. In this investigation, high-resolution (1 m) multibeam echosounder (MBES) depth and backscatter data and derivates, underwater imagery (UI) by video drop-frame, and grab sediment samples, all acquired within 32 km2 of seafloor in offshore Belgian waters, were integrated to produce a random forest (RF) spatial model, predicting the continuous distribution of the seafloor areal cover/m2 of the stones’ grain sizes promoting colonisation by sessile epilithic organisms. A semi-automated UI acquisition, processing, and analytical workflow was set up to quantitatively study the colonisation proportion of different grain sizes, identifying the colonisation potential to begin at stones with grain sizes Ø ≥ 2 cm. This parameter (i.e., % areal cover of stones Ø ≥ 2 cm/m2) was selected as the response variable for spatial predictive modelling. The model output is presented along with a protocol of error and uncertainty estimation. RF is confirmed as an accurate, versatile, and transferable mapping methodology, applicable to area-wide mapping of SNHS. UI is confirmed as an essential aid to acoustic seafloor classification, providing spatially representative numerical observations needed to carry out quantitative seafloor modelling of ecologically relevant parameters. This contribution sheds innovative insights into the ecologically relevant delineation of subtidal natural reef habitat, exploiting state-of-the-art underwater remote sensing and acoustic seafloor classification approaches.
Located in Library / RBINS Staff Publications 2021
First Detections of Culiseta longiareolata (Diptera: Culicidae) in Belgium and the Netherlands: Located in Library / RBINS Staff Publications 2021
Effects of elevational range shift on the morphology and physiology of a carabid beetle invading the sub-Antarctic Kerguelen Islands: Located in Library / RBINS Staff Publications 2020
The new stick insect genus Medauromorpha gen. nov. with one new species from Vietnam and notes on Medauroidea Zompro, 2000 (Phasmida: Phasmatidae: Clitumninae): Located in Library / RBINS Staff Publications 2017
The Picasso stick insect. A striking new species of Calvisia from Vietnam with notes on captive breeding and new methods for incubation of eggs (Phasmida: Diapheromeridae: Necrosciinae): Located in Library / RBINS Staff Publications 2017
Assessing the radiocarbon freshwater reservoir effect for a Northwest-European river system (the Schelde basin, Belgium): The freshwater reservoir effect (FRE) for the Schelde basin (Belgium) is assessed for the Roman, Medieval and early Post-medieval periods by comparing historical and archaeological dates from individual archaeological deposits with radiocarbon dates on the remains of freshwater fish and terrestrial mammals from those same deposits. This is the first time such an assessment has been attempted for the Schelde basin. The FRE offsets prove to be substantial for the historical periods considered. They also differ markedly between fish species and between size classes of a single species. These observations have implications for the evaluation of radiocarbon dates obtained on archaeological remains of humans (and animals) with a substantial amount of freshwater fish into their diet. The data obtained in this study suggest that it will not be easy to correct for any FRE.
Located in Library / RBINS Staff Publications 2018
Speciﬁc initial training standards are needed to dive for science in Europe, Occupational vs . Citizen Science Diving: Today, collaboration between scienti ﬁ c research and civil society is growing signi ﬁ cantly. The general public ’ s curiosity drives it to engage with the scienti ﬁ c process and culture and in the search for solutions to complex issues (economic, social, health, environmental, cultural, educational, or ethical). Clari ﬁ cation is needed to differentiate between occupational scienti ﬁ c activity and citizen-based science. They do not require the same scienti ﬁ c and technical skills despite using similar equipment and their legal and administrative frameworks being totally different. The confusion created by the indiscriminate use of the same term “ scienti ﬁ c diving ” to refer to different training courses and activities compromises the quality of existing occupational standards and, ultimately, has a negative impact on the safety of the activity at work. A clear de ﬁ nition of Citizen Scienti ﬁ c Diving and Occupational Scienti ﬁ c Diving makes it possible to differentiate between the objectives and target groups of these two activities and their legal framework. There is a need to establish an accepted and shared standard in the occupational ﬁ eld and to ensure the mobility of scientists. A long process undertaken by a motivated scienti ﬁ c community (late 1980s-2000s) led to the establishment of European initial training standards for Occupational Scienti ﬁ c Diving through the ESDP-European Scienti ﬁ c Diving Panel ( ﬁ rstly under the aegis of the European Marine Board, now of the MARS-European marine stations network). The quality and general acceptance of these standards by a large part of the European scienti ﬁ c community have already adopted them in the occupational health and safety legislation of seven European countries (Belgium, Finland, France, Germany, Norway, Sweden, and the UK in 2023). Adopting them in other countries ’ health and safety legislation is still desirable. This will increase their recognition, acceptance and use for the bene ﬁ t of scienti ﬁ c work. Building bridges between academic science and non-academic citizen science is possible and this is done by developing coherent projects that produce results that bene ﬁ t both science and society. While distinguishing between the two, as an added value, this approach could better guide the recreational diving training sector in developing a new market.
Located in Library / RBINS Staff Publications 2023
Furostanol saponins and ecdysteroids from plants of the genus Helleborus as phagostimulants and predator deterrents for larvae of two Monophadnus sawfly species.: Located in Library / RBINS Staff Publications 2024

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