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Experimente über zunehmende Schädigungen an Rebstöcken durch die Reblaus Dactulosphaira vitivoliae (Fitch): Mikrokompartimentuntersuchungen im Wurzelsystem

Das Projekt dient der Ursachenforschung von Rebschäden bei Reblausbefall auf unterschiedlich bewirtschafteten Rebflächen. Rebstöcke kontaminierter Versuchsflächen sind im Wurzelbereich mit der Reblaus befallen, jedoch unterscheiden sie sich deutlich in der vegetativen Leistung. In Rebflächen mit kostenextensiver Bewirtschaftung und mangelnder Bodenpflege zeigen die Reben häufig eine Absterbezone, während sie in Anlagen mit guter Bodenpflege trotz Reblausbefalls einen vitalen Wuchszustand aufweisen können. Als Kontrollfläche dienen reblausfreie Rebanlagen, ferner sind ergänzende Topfversuche in Gewächshäusern geplant. Die Untersuchungen sind fokussiert auf das Wurzelsystem mit reblausinduzierten Wurzelveränderungen (Nodositäten) und damit in Frage kommender Interaktionen mit potentiellen Schadorganismen (Mikroorganismen, Nematoden). Sie umfassen populationsbiologische Reaktionen der Rebläuse auf Bewirtschaftungsmaßnahmen (Düngung, Bodenbearbeitung), die Erfassung von Gewebeveränderungen und Aktivitätsspuren an den Saugplätzen der Rebläuse (Nodositäten) und die Lokalisierung und Bestimmung von Mikroorganismen und Nematoden im freien Boden, in der Rhizosphäre und im Wurzelgewebe. Zur Ermittlung des Schädigungsgrades der Wurzeln wird ein Verbraunnungsindex ermittelt.

FZT 15: Der Ozean im Erdsystem; Ocean Margins - Research Topics in Marine Geosciences for the 21st Century, Sub project: Infrastructure, Support and Central Management

The research centre 'Ocean Margins' at the University of Bremen was established in July 2001 to geoscientifically investigate the transitional zones between the oceans and the continents. The work of the research centre is a cooperative effort, with expertise provided by the geosciences department and other departments of the university, as well as by MARUM (Center for Marine Environmental Sciences), the Alfred Wegener Institute for Polar and Marine Research, the Max Planck Institute for Marine Microbiology, the Center for Marine Tropical Ecology, and the Senckenberg Research Institute in Wilhelmshaven. Funded by the DFG, the studies focus on four main research fields: Paleoenvironment, Biogeochemical processes, Sedimentation Processes, and Environmental Impact Research. The term 'Ocean Margin' encompasses the region from the coast, across the shelf and continental slope, to the foot of the slope. Over 60 percent of the world's population live in coastal regions. These people have a long history of exploitation of coastal waters, including the recovery of raw materials and food. Human activity has recently been expanding ever farther out into the ocean, where the ocean margins have become more attractive as centers for hydrocarbon exploration, industrial fishing, and other purposes. The research themes of the centre range from environmental changes in the Tertiary to the impact of recent coastal construction, and from microbial degradation in the sediment to large-scale sediment mass wasting along continental margins. New full professorships and junior professorships have been established within the framework of this research centre. In addition to the primary research activities, a research infrastructure will be made available to outside researchers. Graduate education and the public understanding of science also play an important role. In the course of the first two rounds of the Excellence Initiative, the Research Centre was promoted to that status of a cluster of excellence, which has increased the amount of funding it receives up to the average amount of 6.5 million per annum received by clusters of excellence.

Mineralische Zusammensetzung von Sanden fuer die Kalksandstein-Herstellung

Fuer die Herstellung von Kalksandsteinen werden Quarzsande unterschiedlicher geologischer Herkunft herangezogen. Natuerliche Quarzsande enthalten je nach der geologischen Situation ihrer Entstehungsbedingungen qualitativ und quantitativ unterschiedliche Beimengungen an Begleitmineralien, die die Herstellung von Kalksandsteinprodukten und deren Eigenschaften beeinflussen koennen. Der vorliegende Forschungsbericht ist eine zusammenfassende Darstellung der in Quarzsanden vorkommenden Begleitmineralien. Soweit bekannt, werden die Auswirkungen auf den Hydrothermalprozess und der Einfluss der Minerale auf die Eigenschaftswerte von Kalksandsteinen erlaeutert. Die Zusammenstellung ist durch einen Hinweis auf organische Stoffe und deren schaedliche Wirkung auf die Qualitaet von Kalksandsteinen ergaenzt.

Interaktion Donaustrom - Neue Donau, vor und nach Aufstau in Wien-Freudenau

Im Falle der Errichtung der Staustufe Wien-Freudenau koennte eine wassermengenwirtschaftlich vermehrte Zustroemung an Donauwasser zur Neuen Donau zu einer vermehrten Eutrophierung in dieser fuehren. Vom Ist-Zustand und in Zusammenarbeit mit Hygienikern und Limnologen/Hydrologen wurde und wird weiter versucht, auf die in diesem Zusammenhang massgebenden bestimmenden Faktoren einzugehen.

Size-frequency data of Mya arenaria from Oderbank, Baltic Sea, in June 2021

In the framework of research on impacts of trawling in the western Baltic Sea (DAM pilot mission MGF Baltic Sea), we investigated the population structure of the benthic key species Mya arenaria by measuring shell length to provide the size-frequency distribution in the marine protected area of Oderbank in the Southern Baltic Sea from June 2021. We obtained samples using vanVeen grabs inside the marine protected areas and reference areas nearby.

Size-frequency data of Macoma balthica from Oderbank, Baltic Sea, in June 2021

In the framework of research on impacts of trawling in the western Baltic Sea (DAM pilot mission MGF Baltic Sea), we investigated the population structure of the benthic key species Macoma balthica by measuring shell length to provide the size-frequency distribution in the marine protected area of Oderbank in the Southern Baltic Sea from June 2021. We obtained samples using vanVeen grabs inside the marine protected areas and reference areas nearby.

Size-frequency data of Macoma balthica from Rönnebank, Baltic Sea, in June 2023

In the framework of research on impacts of trawling in the western Baltic Sea (DAM pilot mission MGF Baltic Sea), we investigated the population structure of the benthic key species Macoma balthica by measuring shell length to provide the size-frequency distribution in the marine protected area of Rönnebank in the Southern Baltic Sea from June 2023. We obtained samples using vanVeen grabs inside the marine protected areas and reference areas nearby.

Size-frequency data of Arctica islandia from Fehmarnbelt, Baltic Sea, in June 2020

In the framework of research on impacts of trawling in the western Baltic Sea (DAM pilot mission MGF Baltic Sea), we investigated the population structure of the benthic key species Arctica islandica by measuring shell length to provide the size-frequency distribution in the marine protected area of Fehmarnbelt in the Western Baltic Sea from June 2020. We obtained samples using vanVeen grabs inside the marine protected areas and reference areas nearby.

Seawater carbonate chemistry and benthic foraminifera Ammonia sp. mass, size, and growth rate during experiments, 2013

About 30% of the anthropogenically released CO2 is taken up by the oceans; such uptake causes surface ocean pH to decrease and is commonly referred to as ocean acidification (OA). Foraminifera are one of the most abundant groups of marine calcifiers, estimated to precipitate ca. 50 % of biogenic calcium carbonate in the open oceans. We have compiled the state of the art literature on OA effects on foraminifera, because the majority of OA research on this group was published within the last three years. Disparate responses of this important group of marine calcifiers to OA were reported, highlighting the importance of a process-based understanding of OA effects on foraminifera. We cultured the benthic foraminifer Ammonia sp. under a range of carbonate chemistry manipulation treatments to identify the parameter of the carbonate system causing the observed effects. This parameter identification is the first step towards a process-based understanding. We argue that CO3 is the parameter affecting foraminiferal size-normalized weights (SNWs) and growth rates. Based on the presented data, we can confirm the strong potential of Ammonia sp. foraminiferal SNW as a CO3 proxy.

Chlorophyll depth profiles from 2020-2024, Western Baltic, Germany

In the framework of research on impacts of trawling in the western Baltic Sea (DAM pilot mission MGF Baltic Sea), we measured the depth distribution of chlorophyll-a in order to study bioturbation in three marine protected areas of the Western and Southern Baltic Sea from 2020 – 2024. The marine protected areas are Fehmarnbelt, Oderbank and Rönnebank. We obtained samples using multiple corer inside the marine protected areas and reference areas nearby. During an in situ otter trawling experiment near Heiligendamm, core scuba divers additionally took targeted core samples from trawl track furrows, mounds, the ground net impacted area and control sites.

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