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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.

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.

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).

forest_soil_fauna_densities_grouplevel_2008

<p>Original data comes from a project which takes or took place as part of the DFG priority program "Exploratories for large-scale and long-term functional biodiversity research". The data is stored together with descriptive metadata, in combination called a dataset, in the project repository (https://www.bexis.uni-jena.de). Species information was extracted from that original dataset. The second paragraph is part of the metadata of the original dataset.</p> <p>Changes in soil food web structure of the decomposer system with land use intensity in forest systems</p>

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.

Stable oxygen isotope ratios of pore water from IODP Site 347-M0059

Stable isotope ratios of benthic foraminifera from IODP Site 347-M0059

Geochemistry of benthic foraminifera from IODP Site 347-M0059

Solution based trace element concentration of IODP Site 347-M0059

Benthic foraminifera assemblages of IODP Site 347-M0059

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