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CO2 degassing from karstic springs in Southern Germany

This study examines characteristics of dissolved inorganic carbon (DIC) and partial pressures of CO2 characteristics (pCO2) in the source springs and headwaters of four karstic watersheds, via dissolved inorganic carbon concentration and stable carbon isotope measurements. All four spring sources are located in Southern Germany and were measured for water chemistry and stable isotopes with nearby headwater stream points, which were located up to 100 m downstream of the discharge points. Seasonal sampling covered winter, spring, summer, and autumn in 2018.

Stable isotope analysis of the common periwinkle Littorina littorea depending on infection status and seasonality

Littorina littorea was collected at the study site. The foot of Littorina littorea was used for stable isotope analysis (δ15N and δ13C). The stable isotope composition of possible food sources was also determined. Samples were taken in spring, summer and autumn. For the analysis a diet tissue discrimination factor (DTDF) of 2.4 for δ15N and 1.0 for δ13C was subtracted, respectively. The data in the sheet are the raw data without the DTDF.

Spatial pattern analysis for habitat composition and availability of food sources at Möltenort, Kiel Bight

The habitat at Möltenort was characterised with a 24 cm x 24 cm metal frame, which was thrown parallel to the coast 30 times within the 100 m transect. Coverage of Amphibalanus spp., Fucus vesiculosus, Gracilaria vermiculophylla, Mytilus spp., sand, stone, Ulva sp., and other ("other" indicating any category not mentioned in the list), was measured in 7 different percentage coverage groups (0, 1-5, 6-10, 11-20, 21-50, 51-75, or 76-100). Measurements were taken in spring, summer and autumn.

Habitat choice of the common periwinkle Littorina littorea depending on infection status and seasonality

Littorina littorea were collected from the habitat, screened for infection and marked before being released back into the environment. After 24 hours they were recollected and the habitat in which they were found was recorded. Their infection status was then checked by dissection.

The diet contribution and habitat selection of the common periwinkle Littorina littorea depending on infection with parasites and seasonality

The common periwinkle Littorina littorea is an ecologically important grazer and serves as the first intermediate host for several trematode species in the Baltic Sea, especially for the fluke Cryptocotyle lingua. In this series of experiments and analyses, we tested whether the food sources contributing to the diet and the habitat selection differ depending on the infection status of the periwinkle and the season. (1) A spatial pattern analysis was conducted to investigate the habitat composition and availability of food sources at the study site Möltenort, Kiel Bight (54.37°N, 10.19°E), (2) the habitat choice of the periwinkle was observed in-situ by a mark and recapture experiment, and (3) the composition of the diet of L. littorea (based on stable isotope composition of carbon and nitrogen isotopes) was analysed. All experiments were conducted in spring, summer and autumn.

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.

TOC, TIC, TN and TS contents and stable isotope signatures (δ13C of TOC, δ15N, δ34S) of fine-grained saltmarsh deposits of the barrier island Spiekeroog at the southern North Sea Coast

The dataset compiles total organic carbon (TOC), total inorganic carbon (TIC), total nitrogen (TN) and total sulfur (TS) contents and stable isotope signatures (δ13C of TOC, δ15N, δ34S) of fine-grained deposits (clay, loam) over sandy subsoils of the saltmarsh of the barrier island Spiekeroog at the southern North Sea coast. Sampling was performed in September 2016 along three transects spanning from the high saltmarsh to the pioneer zone. At each sample point, soil samples were taken from the first 5 cm of the upper part (top samples) and from the deepest 5 cm of the lower part (bottom samples) of the fine-grained deposit. If the fine-grained deposit layer had a thickness < 10 cm, only one bulk soil sample (single samples) was taken for the depth range equal to the deposit thickness. Samples were ground to fine powder. TIC was measured on oven-dried samples coulometrically with an Analytik Jena multi EA 4000 analyzer. The total carbon (TC), TN, and TS were analyzed using a Thermo Scientific Flash EA Isolink Elemental Analyzer. The TOC contents were calculated as the difference between TC and TIC. TOC, TN, and TS contents are reported based on the original dry mass. For isotope analysis, dried and homogenized samples were weighed in tin cups and combusted in a Thermo Scientific Flash EA Isolink Elemental Analyzer, connected to a Thermo Finnigan MAT 253 gas mass spectrometer via a Thermo Conflo IV split interface. The δ13C values of TOC were measured after decalcification of the ground powders with p. a. grade HCl. The TN and δ34S analysis were carried out on a separate aliquot of sample powder. The isotope results are given in the conventional δ-notation.

TOC, TIC, TN and TS contents and stable isotope signatures (δ13C of TOC, δ15N, δ34S) of fine-grained saltmarsh deposits of the barrier island Spiekeroog at the southern North Sea Coast

The dataset compiles total organic carbon (TOC), total inorganic carbon (TIC), total nitrogen (TN) and total sulfur (TS) contents and stable isotope signatures (δ13C of TOC, δ15N, δ34S) of fine-grained deposits (clay, loam) over sandy subsoils of the saltmarsh of the barrier island Spiekeroog at the southern North Sea coast. Sampling was performed in September 2016 along three transects spanning from the high saltmarsh to the pioneer zone. At each sample point, soil samples were taken from the first 5 cm of the upper part (top samples) and from the deepest 5 cm of the lower part (bottom samples) of the fine-grained deposit. If the fine-grained deposit layer had a thickness < 10 cm, only one bulk soil sample (single samples) was taken for the depth range equal to the deposit thickness. Samples were ground to fine powder. TIC was measured on oven-dried samples coulometrically with an Analytik Jena multi EA 4000 analyzer. The total carbon (TC), TN, and TS were analyzed using a Thermo Scientific Flash EA Isolink Elemental Analyzer. The TOC contents were calculated as the difference between TC and TIC. TOC, TN, and TS contents are reported based on the original dry mass. For isotope analysis, dried and homogenized samples were weighed in tin cups and combusted in a Thermo Scientific Flash EA Isolink Elemental Analyzer, connected to a Thermo Finnigan MAT 253 gas mass spectrometer via a Thermo Conflo IV split interface. The δ13C values of TOC were measured after decalcification of the ground powders with p. a. grade HCl. The TN and δ34S analysis were carried out on a separate aliquot of sample powder. The isotope results are given in the conventional δ-notation.

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).

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.

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