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Early Miocene intensification of the North African hydrological cycle: multi-proxy evidence from the shelf carbonates of Malta - Geochemical data

A total of 140 samples were collected from the il-Blata section outcropping on the Mediterranean Island of Malta (base of section at 35.9004˚N, 14.3309˚E, top of section at 35.9000˚N, 14.3314˚E). 16 of these samples were selected to determine the 87Sr/86Sr in the bulk sediment and used to generate numerical ages using the LOWESS FIT for Sr-Stratigraphy (McArthur et al., 2012). All 87Sr/86Sr measurements conducted at the University of Geneva using a Thermo Neptune PLUS Multi-Collector inductively coupled plasma mass spectrometer. Data and numerical age model presented in table S1. The εNd data from (Bialik et al., 2019) were recalibrated to fit the new age model and presented in table S2. The percentage carbonate matter was measured using a FOGl digital calcimeter at the University of Malta (table S3). Dry powders were used to generate a stable isotope (δ18O & δ13C) record (table S4), all measurements were conducted on a Gasbench II coupled to a Thermo Delta V Advantage isotope ratio mass spectrometer at the School of Earth and Environmental Sciences, Cardiff University. Dry bulk sediment powders were also used to obtain major element composition and calculate element ratios Sr/Ca, Ti/Al, K/Al, Zr/Al, Si/Ti. All element measurements were conducted at The School of Earth and Environmental Sciences, Cardiff University using a hand-held Olympus Delta Innov-X XRF gun. Element data presented in table S5. Mean values of the ratios Sr/Ca, Ti/Al, K/Al, Zr/Al and Si/Ti were obtained for three different parts in the section in order to determine regime changes (table S6).

Spatial characterization of the composition of the isotope hydrobiogeochemistry along the Warnow River

A spatial study of the isotopic hydrobiogeochemical composition along the the Warnow River, which drains into the southern Baltic Sea, was carried out. The sampling took place on 29-30 April 2019 from the source up to the estuary. In addition to in situ physico-chemical parameters, surface water was sampled using a telescopic rod and a plastic beaker and preserved for further analysis. Major and trace elements and selected nutrients were measured using an ICP-OES (iCAP, 7400, Duo Thermo Fischer Scientific). Ammonium (NH4) and nitrate (NO3) concentrations were measured using a QuAAtro autoanalyzer system. Chloride (Cl) concentrations were measured by electrical potential difference precipitation with 0.05 M AgNO3. Dissolved inorganic carbon (DIC), and δ13CDIC were measured using an isotope gas mass spectrometer (MAT 253) coupled to a Gasbench II. Dissolved organic carbon (DOC) and δ13CDOC using an Elementar iso TOC cube with Thermo Electron MAT 253 mass spectrometry, δ18OH2O, and δ2HH2O using a CRDS system (laser cavity-ring-down-spectroscopy, Picarro L2140- I). δ34S and δ18O of SO4 using a gas-isotope mass spectrometer MAT253 (Thermo-Finnigan) with EA-Isolink (Thermo-Fisher-Scientific).

Stabile Isotopenanalyse der Nahrung von Elateridenlarven

Die Nahrungswahl von Drahtwürmern (Coleoptera: Elateridae) im Agrarland und ihre Beeinflussung durch Umweltfaktoren analysiert mittels Stabiler Isotope. Als Drahtwürmer werden die Larven der Schnellkäfer (Coleoptera: Elateridae) bezeichnet, welche häufig in Agrarböden anzutreffen sind. Die meisten Drahtwurmarten sind polyphag und fressen neben Wurzeln auch abgestorbenes Pflanzenmaterial. Bestimmte Arten treten jedoch weltweit als bedeutende Schädlinge an verschiedensten Kulturpflanzen auf. Es wird angenommen, dass bestimmte Bodenparameter (z.B. Humusgehalt, Feuchte) und die Fruchtfolge die Nahrungswahl der Drahtwürmer entscheidend beeinflussen. Im Freiland konnten diese Beziehungen bis heute jedoch nicht nachgewiesen werden. Ein besseres Verständnis der Wechselwirkung zwischen diesen Faktoren und der Nahrungswahl der Drahtwürmer würde aber die Einschätzung der tatsächlichen Rolle bestimmter Drahtwurmarten erheblich erleichtern und eine Basis für die Vorhersage und Kontrolle von Drahtwurmschäden darstellen. Im vorliegenden Projekt wird erstmals die Stabile-Isotopen-Methode angewandt, um die Nahrungswahl von Elateridenlarven zu untersuchen. Dabei geben die unter Freilandbedingungen gewonnenen Isotopendaten der Drahtwürmer darüber Auskunft, von welchen Nahrungssubstraten sich diese Tiere ernähren. Zusätzliche Laborexperimente ergänzen die Befunde aus dem Freiland und helfen bei ihrer Interpretation. Um allgemeine Aussagen über die Nahrungswahl von Drahtwürmern in Mitteleuropa zu erhalten, werden verschiedenste Standorte in Österreich und Deutschland beprobt. Weiters wird das Nahrungswahlverhalten mit bestimmten Bodenparametern in Beziehung gesetzt, um zu analysieren, wie diese Parameter die Nahrungswahl der Drahtwürmer und ihr Schadpotential beeinflussen. Die Ergebnisse dieses Projektes stellen damit eine Basis für alle weiteren Schritte zur Entwicklung von Regulationsmaßnahmen bei Drahtwürmern dar.

Stable carbon, oxygen and clumped isotope data of land snails from natural populations across Europe

These data include carbon, oxygen and clumped isotope compositions of shells of natural populations of three land snail species (Clausilia pumila, Succinella oblonga and Trochulus hispidus) across Europe. δ¹³C, δ¹⁸O and Δ₄₇ values of snail shells from field-collections were determined in two laboratories (Institute for Nuclear Research, Debrecen, and Geological Institute, ETH Zürich) using IRMS. Detailed analysis and interpretations of the results obtained can be read in the original publication.

Calcium carbonate from the Il-Blata section, Malta Island (S3)

Compilation of stable nitrogen and carbon isotope ratios of marine biota from the central and Northeast Atlantic, and the Mediterranean Sea

Bulk stable isotope ratios, primarily of carbon (δ13C) and nitrogen (δ15N), are increasingly used to examine predator-prey interactions and food web structure. We compiled δ13C and δ15N values of marine taxa from 56 published sources to support investigations on trophic interactions in mesopelagic food webs and assess the importance of mesopelagic organisms in the marine ecosystem. A total of 2095 records were collected, representing 8716 individual organisms from 349 unique species or genera sampled across the central and Northeast Atlantic, and the Mediterranean Sea, between 1905 and 2020. Records include 185 benthic and pelagic fish, 47 cephalopods, 31 marine mammals, 30 crustaceans, 26 elasmobranchs, 16 seabirds, 4 marine turtles, 4 jelly fish, 3 copepods, 2 salps, in addition to data from several organisms only identified to higher taxonomic ranks (family or above). The dataset includes isotopic ratios measured in the tissues or in the whole body of individual organisms, or mean values (and standard deviations) from pooled samples. Because lipids have more negative δ13C values relative to other major biochemical compounds in plant and animal tissues (DeNiro & Epstein, 1977), many studies correct for the lipid effect by extracting lipids from samples before analysis, or a posteriori, through mathematical corrections (Post, 2002). Therefore, δ13C values were reported as uncorrected, lipid-extracted, or mathematically-corrected. When available, the total organic carbon to nitrogen ratio (C:N) was included. For each data record, we also provided the sampling location, geographic coordinates, month and year of sample collection, method of sample collection, taxonomic ranks (phylum, class, order, family), number and size (or size range) of sampled organisms, as well as the reference and DOI of the original data source, for further details on the samples analysed and/or the analytical techniques used.

Meterological and stable carbon, oxygen and clumped isotope data of land snails from Europe

These data include site information and collection dates of land snails (Clausilia pumila, Succinella oblonga, Trochulus hispidus), meteorological data of collection sites using the ClimateEU software, as well as carbon, oxygen and clumped isotope compositions of snail shells of the mentioned three species from culturing experiments and natural populations across Europe. During the laboratory experiments at the University of Lodz (Poland) individuals of the three species were kept at 12, 18 and 24 °C temperatures in climate chambers, fed exclusively by fresh lettuce and humidity was controlled using tap water (δ¹⁸O: -9.29 ±0.52 ‰, V-SMOW). δ¹³C, δ¹⁸O and Δ₄₇ values of snail shells from lab experiments and field-collections were determined in two laboratories (Institute for Nuclear Research, Debrecen, and Geological Institute, ETH Zürich) using IRMS. Detailed analysis and interpretations of the results obtained can be read in the original publication.

Dataset to: Sourcing and Long-Range Transport of Particulate Organic Matter in River Bedload: Rio Bermejo, Argentina

The data package encompasses field data of clastic and organic sediment, river width and flow velocities of six river transects along the Rio Bermejo, Argentina. The laboratory data entails long-chain n-alkanes and d2H and d13C values of organic matter (soil, deposited sediment, suspended sediment (published by Repasch et al., 2020), leaf litter, floating organic matter, and bedload organic matter from the Rio Bermejo catchment. It further contains the bedload organic matter and estimated bedload organic carbon fluxes of six river transects along the Rio Bermejo. Fluvial transport of organic carbon from the terrestrial biosphere to the oceans is an important term in the global carbon cycle. Traditionally, the long-term burial flux of fluvial particulate organic carbon (POC) is estimated using river suspended sediment flux; however, organic carbon can also travel in river bedload as coarse particulate organic matter (POMBed). Estimates of fluvial POC export to the ocean are highly uncertain because few studies document POMbed sources, flux and evolution during long-distance fluvial transport from uplands to ocean basins. This knowledge gap limits our ability to determine the global terrestrial organic carbon burial flux. In this study we investigate the flux, sources and transformations of POMBed during fluvial transport over a ~1300 km long reach of the Rio Bermejo, Argentina, which has no tributary inputs. To constrain sourcing of POMBed, we analysed the composition and stable hydrogen and carbon isotope ratios (δ2H, δ13C) of plant wax biomarkers from POMBed at six locations along the Rio Bermejo, and compared this to samples of suspended sediment, soil, leaf litter and floating organic debris (POMfloat) from both the lowland and headwater river system. Across all samples, we found no discernible differences in n-alkane average chain length or nC29 δ13C, indicting a common origin for all sampled POMBed. We define three potential POMBed sources: Coarse organic debris we sampled at distinct elevations in the catchment: floodplain leaf litter, headwater leaf litter, and headwater POMfloat. We aim to understand the mixing range of the widely spread POMBed. We determine the range of a possible POMBed mixing signal of the sources within the geochemical parameters, and in addition, determine potential missing POMBed sources, using a mixing-space model developed by (Smith et al., 2013). Leaf litter and POMfloat nC29 δ2H values decrease with elevation, making it a useful proxy for POMBed source elevation. Biomarker δ2H values suggest that POMBed is a mix of distally-derived headwater and locally-recruited floodplain sources at all sampling locations. These results indicate that POMBed can be preserved during transport through lowland rivers for hundreds of kilometres. However, the POMBed flux decreases with increasing transport distance, suggesting mechanical comminution of these coarse organic particles, and progressive transfer into the suspended load. Our provisional estimates suggest that the carbon flux from POMBed comprises less than 1 percent of the suspended load POC flux in the Rio Bermejo. While this represents a small portion of the river POC flux, this coarse, high density material likely has a higher probability of deposition and burial in sedimentary basins, potentially allowing it to be more effective in long-term CO2 drawdown relative to fine suspended particles. Because the rate and ratio of POMBed transport versus comminution likely varies across tectonic and climatic settings, additional research is needed to determine the importance of POMBed in the global carbon cycle.

Information and meterological data of collection sites of land snails from Europe

The first table provide data on the meteorological conditions of the sites where land snails were collected, and the calculated stable oxygen isotope compositions of local rainwater.

Compilation of data to assess trophic interactions in mesopelagic food webs in the central and Northeast Atlantic, and in the Mediterranean Sea

Mesopelagic organisms play a critical role in marine ecosystems, channelling energy and organic matter across food webs and serving as the primary prey for many open-ocean predators. Nevertheless, trophic pathways involving mesopelagic organisms are poorly understood and their contribution to food web structure remains difficult to assess (St. John et al., 2016). Existing data to assess mesopelagic feeding interactions and energy transfer are scattered in the literature or remain unpublished, making it difficult to locate and use such datasets. As part of the EU funded project SUMMER - Sustainable Management of Mesopelagic Resources H2020-BG-2018-2, GA: 817806) (https://summerh2020.eu/), we created MesopTroph, a georeferenced database of diet, trophic biogeochemical markers, and energy content of mesopelagic organisms and other marine taxa from the Northeast Atlantic and Mediterranean Sea, compiled from 191 published and non-published sources. MesopTroph includes seven datasets: (i) diet compositions from stomach content analysis, (ii) stable isotopes of carbon and nitrogen (δ13C and δ15N), (iii) fatty acid trophic markers (FATM), (iv) major and trace elements, (v) energy density, (vi) estimates of diet proportions, and (vii) trophic positions. The database contains information from 4918 samples, representing 51119 specimens from 499 species or genera, covering a wide range of trophic guilds and taxonomic groups. Metadata provided for each record include the location, dates and method of sample collection, taxonomic ranks (phylum, class, order, family), number and size (or size range) of sampled organisms, method/model used in data analysis, reference and DOI of the original data source. Compiled data were checked for errors, missing information, and to avoid duplicate entries, and scientific names and taxonomy were standardized.

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