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Timeseries of binned benthic stable carbon isotope from ODP Site 162-982,130-807 and ODP Site 162-982

This dataset contains C. wuellerstorfi stable carbon isotope values binned by marine isotope stage from ODP Site 162-807 and ODP Site 162-982 that span the last 4.5 million years (Feng et al. 2022; Venz et al. 1999, 2002; Hodell & Venz-Curtis 2006). This isotope gradient reflects the accumulation of respired and disequilibrium carbon in the deep Pacific ocean relative to the North Atlantic. Also included are binned probstack δ18O (Ahn et al., 2017) and ΔGMST (Clark et al., 2024) values for comparison to the binned stable carbon isotope values.

Forschergruppe (FOR) 918: Carbon flow on belowground food webs assessed by isotope tracers, Nematodes as link between microbial and faunal food web

The proposed project examines the nematode fauna at the two field experiments 'Long-term recalcitrant C input' and 'Carbon flow via the herbivore and detrital food chain'. A gradient from resource rich to deeper oligotrophe habitats, i.e. from high to low diverse food webs, is investigated. The impact of resource availability and quality (recalcitrant versus labile) and presence or absence of living plants (rhizosphere versus detritusphere) on the nematode population are assessed. Insight into micro-food web structure is gained by application of the nematode faunal analysis concept, based on the enrichment, structure and channel index. In laboratory model systems carbon flux rates for food web links are determined between bacteria/fungi and their nematode grazers for dominant taxa in the arable field. Further, carbon leakage from plant roots induced by herbivore nematode is studied as link between root and bacterial energy channels. By using 13C/12C stable isotope probing (FA-SIP) fatty acids serve as major carbon currency. Coupling qualitative and quantitative data on nematode field populations, with carbon flow via biomarker fatty acids in microorganisms and grazers will allow to connect microbial and faunal food web, and to directly link nematode functional groups with specific processes in the soil carbon cycle.

Results of palynological analysis from 2020 of the varved MO-05 core from Lake Mondsee (Austria) section (249-526 cm)

This study reports a precisely dated pollen record with a 20-year resolution from the varved sediments of Lake Mondsee in the north-eastern European Alps (47°49′N, 13°24′E, 481 m above sea level). The analysed part of core spans the interval between 1500 BCE and 500 CE and allows changes in vegetation composition in relation to climatic changes and human activities in the catchment to be inferred. Intervals of distinct but modest human impact are identified at ca. 1450-1220, 740-490 and 340-190 BCE and from 80 BCE to 180 CE. While the first two intervals are synchronous with prominent salt mining phases during the Bronze Age and Early Iron Age at the nearby UNESCO World Heritage Site of Hallstatt, the last two intervals fall within the Late Iron Age and Roman Imperial Era, respectively. Comparison with published records of extreme runoff events obtained from the same sediment core shows that human activities (including agriculture and logging) around Lake Mondsee were low during intervals of high flood frequency as indicated by a higher number of intercalated detrital event layers, but intensified during hydrologically stable intervals. Comparison of the pollen percentages of arboreal taxa with the stable oxygen isotope and potassium ion records of the NGRIP and GISP2 ice cores from Greenland reveals significant positive correlations for Fagus and negative correlations for Betula and Alnus. This underlines the sensitivity of vegetation around Lake Mondsee to temperature fluctuations in the North Atlantic as well as to moisture fluctuations controlled by changes in the intensity of the Siberian High and the North Atlantic Oscillation (NAO) regime.

Wechselwirkungen zwischen saisonale arktische Meereisprozessen und Stabilität der Halokline – auf dem Weg zum Verständnis arktischer Gas- und Stoffflüsse

In Folge des globalen Klimawandels hat sich die Meereisdecke in der Arktis dramatisch verändert. Im derzeitigen Zustand spielt die arktische Eisdecke eine wichtige Rolle; so schirmt sie das Oberflächenwasser, die sogenannte arktische Halokline (Salzgehaltsschichtung), von der Erwärmung durch die sommerliche Sonneneinstrahlung ab. Zudem wird die Halokline durch die Salze, welches beim Gefrierprozess des Meerwassers aus der Kristallstruktur austritt, gebildet und stabilisiert. Gleichzeitig wirkt die Halokline als Barriere zwischen der Eisdecke und dem darunter liegenden warmen atlantischen Wasser und trägt so zum Erhalt der arktischen Meereisdecke bei. Dieses Gleichgewicht ist nun durch die insgesamt wesentlich dünnere arktische Meereisdecke und ihre verringerte sommerliche Ausdehnung gestört. Im Meerwasser sind zudem Gase und biogeochemisch wichtige Spurenstoffen enthalten. Diese werden durch die Gefrierprozesse eingeschlossen, beeinflusst und wieder ausgestoßen. So beeinflusst die Meereisdecke die Gas- und Stoffflüsse zwischen Atmosphäre, Eis und oberer Wasserschicht. Durch die Eisbewegung findet außerdem ein Transport statt z.B. in der sogenannten Transpolarendrift von den sibirischen Schelfgebieten, über den Nordpol, südwärts bis ins europäische Nordmeer. Nun wird mit den weitreichenden Veränderungen des globalen und arktischen Klimawandels bereits von der „neuen Arktis“ gesprochen, da angenommen wird, dass sich die Arktis bereits in einem neuen Funktionsmodus befindet. Dabei ist jedoch weitgehend unbekannt wie dieses neue System funktioniert, sich weiterentwickelt und wie sich dies auf die Eisbildungsprozesse und damit die Stabilität der Halokline und die damit verbundenen Gas- und Stoffflüsse auswirkt. Für solche Untersuchungen werden über den Jahresverlauf Proben der oberen Wassersäule und der Eisdecke benötigt. Ermöglicht wird dies durch die wissenschaftliche Initiative MOSAiC. Mithilfe der stabilen Isotope des Wassers (?18O und ?D) aus dem Eis und der Wassersäule kann Rückschlüsse auf die Herkunftswässer und den Gefrierprozess gezogen werden und diese Ergebnisse sollen in direkten Zusammenhang mit Gas- und biogeochemischen Stoffuntersuchungen (aus Partnerprojekten) gesetzt werden. Dabei können z.B. Stürme, Schmelzprozesse, Schneebedeckung, Teichbildung und Alterungseffekte des Eises eine Rolle spielen. Untersucht wird parallel die Veränderung der Wassersäule welche z.B. durch Wärmetransport, wiederum die Eisdecke beeinflussen kann.Diese prozessorientierten Untersuchungen der saisonalen Eisbildungsprozesse in Eis und Wassersäule der zentralen Arktis, werden einen wichtigen Beitrag zum Verständnis der Stabilität der arktischen Halokline und der arktischen Gas- und Stoffflüsse liefern. Da sich die Gase und Stoffe nicht-konservativ verhalten, während die Isotope im Gefrierprozess konservativ sind, erwarten wir aus der Diskrepanz wiederum wichtige Informationen z. B. über wiederholtes Einfrieren von Süßwasserbeimengungen ableiten zu können.

Can the resistance and resilience of trees to drought be increased through thinning to adapt forests to climate change?

Recent and predicted increases in extremely dry and hot summers emphasise the need for silvicultural approaches to increase the drought tolerance of existing forests in the short-term, before adaptation through species changes may be possible. We aim to investigate whether resistance during droughts, as well as the recovery following drought events (resilience), can be increased by allocating more growing space to individual trees through thinning. Thinning increases access of promoted trees to soil stored water, as long as this is available. However, these trees may also be disadvantaged through a higher transpirational surface, or the increased neighbourhood competition by ground vegetation. To assess whether trees with different growing space differ in drought tolerance, tree discs and cores from thinning experiments of Pinus sylvestris and Pseudotsuga menziesii stands will be used to examine transpirational stress and growth reduction during previous droughts as well as their subsequent recovery. Dendroecology and stable isotopes of carbon and oxygen in tree-rings will be used to quantify how assimilation rate and stomatal conductance were altered through thinning. The results will provide crucial information for the development of short-term silvicultural adaptation strategies to adapt forest ecosystems to climate change. In addition, this study will improve our understanding of the relationship between resistance and resilience of trees in relation to extreme stress events.

Compilation of global Archean and Paleoproterozoic sanukitoid geochemical data

Sanukitoids, also referred to as high-Mg diorites, are a distinctive type of igneous rock from the late Archean-early Proterozoic, and are characterised by enrichment in both compatible elements (e.g. Mg, Ni, Cr) and incompatible elements (e.g. Ba, Sr, light rare earth elements). Their geochemistry is typically interpreted as recording petrogenesis of their parental magmas via interaction between mantle peridotite and recycled crust-derived component (e.g. metabasite melts, sediment melts, aqueous fluids), and is often considered to be "transitional" between that of Archean sodic tonalite-trondhjemite-granodiorite (TTG) suites and post-Archean potassic granites. This dataset presents a global compilation of all Archean-Paleoproterozoic rocks that have been described as "sanukitoid" in published literature, and consists of over 3600 individual samples. Whole rock major and trace element concentrations, radiogenic isotope compositions and stable isotope compositions are compiled in the dataset alongside reported magmatic ages of the samples. The dataset is provided both as an Excel workbook divided by craton (file: 2025-003_Spencer-et-al_Sanukitoid-Compilation.xlsx) and as a single CSV file (file: 2025-003_Spencer-et-al_Sanukitoid-Compilation.csv). Sanukitoid magmatism has been described on almost every Archean craton globally. Most reported sanukitoid magmatism occurred during the late Mesoarchean-Neoarchean (2.95 - 2.5 Ga), with another peak in sanukitoid magmatism in the mid-Paleoproterozoic (2.2 - 2.0 Ga). Older sanukitoid occurrences dating back to the Paleoarchean (>3.2 Ga) are also described in the literature.

Water isotope time series (March 2020 - March 2021) of samples collected at A. P. Møller Skolen, Kleine Breite, Schlei

Time series of stable isotopes (δ2H and δ18O) were analyzed in water samples collected near the A. P. Møller Skolen, Schleswig (Kleine Breite, Schlei), in biweekly to monthly intervals between March 2020 and March 2021. Water was sampled with a pipette from ca. 0.5 m below water surface and directly transferred into a measurement vial. Isotope analysis was conducted at IGB Berlin, using a Picarro L2130-i cavity ring-down spectrometer. Water chemical parameters were measured in-situ with a modular WTW 3440 multiparameter devices and regularly calibrated conductivity cells (MPP 930 IDS, TetraCon® 925-P). The data give information about the seasonal isotope amplitude at the sampled locations and about spatial variability along the transects.

Seasonal water isotope values in eastern German lakes and rivers (Spree, Dahme, Elster and Mulde systems) in March, July, October 2022, and March 2023

Water isotopes (δ²H and δ¹⁸O) were analyzed in samples from lakes and rivers in eastern Germany. This sub-dataset is derived from water samples collected from lake and river shores. Seasonal samples were collected in March, July, October 2022, and in March 2023, with a plastic syringe from 20-50 cm depth below water surface and directly filtered and transferred into a measurement vial. Stable isotope analysis was conducted at IGB Berlin, using a Picarro L2130-i cavity ring-down spectrometer. Measurement uncertainty was quantified to <0.5 ‰ for δ²H and <0.2 ‰ for δ¹⁸O. Water chemical parameters were determined in-situ with a portable WTW-multiparameter probe. The data give information about the seasonal isotope amplitude at the sampled spots and about spatial isotope variability in different branches of the associated river systems.

Water isotope time series (March 2020 - March 2021) of samples collected in Kloster, Hiddensee

Time series of stable isotopes (δ2H and δ18O) were analyzed in water samples taken near the harbour of Kloster (Hiddensee), in biweekly to monthly intervals between March 2020 and March 2021. Water was sampled with a pipette from ca. 0.5 m below water surface and directly transferred into a measurement vial. Isotope analysis was conducted at IGB Berlin, using a Picarro L2130-i cavity ring-down spectrometer. Water chemical parameters were measured in-situ with WTW multiparameter measurement devices. The data give information about the seasonal isotope amplitude at the sampled locations and about spatial variability along the transects.

Agricultural And Aquaculture Facilities / Tierhaltungs- und Aufzuchtanlagen in Brandenburg

Der Datensatz Agricultural And Aquaculture Facilities / Tierhaltungs- und Aufzuchtanlagen in Brandenburg ist die Datengrundlage der interoperablen INSPIRE-Darstellungs- (WMS) und Downloaddienste (WFS): Tierhaltungsanlagen nach BImSchG in Brandenburg - Interoperabler INSPIRE View-Service (WMS-AF-TIERE) Tierhaltungsanlagen nach BImSchG in Brandenburg - Interoperabler INSPIRE Download-Service (WFS-AF-TIERE) Der Datenbestand beinhaltet die Punktdaten zu den betriebenen Tierhaltungsanlagen aus dem Anlageninformationssystem LIS-A. Die Angaben zu den Anlagen enthalten jeweils den Standort und die genehmigte Leistung. Dabei erfolgte eine sog. Schematransformation und Belegung der INSPIRE-relevanten Attribute. Der Datensatz Agricultural And Aquaculture Facilities / Tierhaltungs- und Aufzuchtanlagen in Brandenburg ist die Datengrundlage der interoperablen INSPIRE-Darstellungs- (WMS) und Downloaddienste (WFS): Tierhaltungsanlagen nach BImSchG in Brandenburg - Interoperabler INSPIRE View-Service (WMS-AF-TIERE) Tierhaltungsanlagen nach BImSchG in Brandenburg - Interoperabler INSPIRE Download-Service (WFS-AF-TIERE) Der Datenbestand beinhaltet die Punktdaten zu den betriebenen Tierhaltungsanlagen aus dem Anlageninformationssystem LIS-A. Die Angaben zu den Anlagen enthalten jeweils den Standort und die genehmigte Leistung. Dabei erfolgte eine sog. Schematransformation und Belegung der INSPIRE-relevanten Attribute. Der Datensatz Agricultural And Aquaculture Facilities / Tierhaltungs- und Aufzuchtanlagen in Brandenburg ist die Datengrundlage der interoperablen INSPIRE-Darstellungs- (WMS) und Downloaddienste (WFS): Tierhaltungsanlagen nach BImSchG in Brandenburg - Interoperabler INSPIRE View-Service (WMS-AF-TIERE) Tierhaltungsanlagen nach BImSchG in Brandenburg - Interoperabler INSPIRE Download-Service (WFS-AF-TIERE) Der Datenbestand beinhaltet die Punktdaten zu den betriebenen Tierhaltungsanlagen aus dem Anlageninformationssystem LIS-A. Die Angaben zu den Anlagen enthalten jeweils den Standort und die genehmigte Leistung. Dabei erfolgte eine sog. Schematransformation und Belegung der INSPIRE-relevanten Attribute.

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