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Multibeam bathymetry processed data (dataset compilation) of RV POLARSTERN & RV MARIA S. MERIAN during 44 cruises from 1984 to 2024, Fram Strait, Greenland Sea, Arctic Ocean

The Long-Term Ecological Research observatory HAUSGARTEN was established by the Alfred-Wegener-Institut Helmholtz-Zentrum für Polar- und Meeresforschung in the Fram Strait in summer 1999 to detect and track the impact of large-scale environmental changes on the marine ecosystem in the transition zone between the northern North Atlantic and the central Arctic Ocean. In this area, bathymetric data have been recorded with multibeam echosounders during 44 research expeditions on RV Polarstern and RV Maria S. Merian since 1984. From these data, a digital elevation model was generated and geostatistical analyses were performed to calculate geospatial derivatives and quantitative terrain descriptors for subsequent terrain analyses and habitat mapping. The dataset covers an area from 78°N to 81°N and 6°W to 12°E. To create the data product, archive data was used from seven different multibeam echosounders in various raw data formats. This data has been processed and cleaned with CARIS HIPS & SIPS, including sound velocity correction for datasets from 1999 and newer. Older datasets are calculated with a static sound velocity of 1500 m/s. Soundings where exported for gridding with Generic Mapping Tools (GMT) nearneighbor. The resulting Digital Elevation Model (DEM) is in the WGS84/Arctic Polar Stereographic (EPSG:3995) projection with a cell size of 100m x 100m. The hillshade was computed with a combination of slope and synthetic illumination with a vertical exaggeration of 10. Slope inclination was calculated with GDAL tool Slope with the formula of Zevenbergen and Thorne (1987) in degree. Terrain Ruggedness Index (TRI) was computed with the QGIS tool Ruggedness index following the approach of Riley et al. (1999) in meters. For the Bathymetric Position Indices (BPI), focal statistics have been calculated with the GRASS tool "r.neighbors" and the QGIS raster calculator following the concept of the Topographic Position Index (Weiss, 2001) with a circular reference area of 99 cells (broad) and 9 cells (fine). The additional coverage polygon layer gives and overview on the used datasets and their corresponding metadata. The map gives an overview on the LTER HAUSGARTEN area and the HAUSGARTEN 2024 DEM.

Untersuchungen mit oben offenen Experimentierkammern zur Auswirkung bestimmter Luftschadstoffe auf Gesundheitszustand und Wachtstum von Forstpflanzen

Seit Beginn der 80er Jahre wird in der Ursachenforschung der Waldschaeden bestimmten Luftschadstoffen eine entscheidende Rolle beigemessen. Aus diesem Grund wurde von der Forstlichen Versuchs- und Forschungsanstalt Baden-Wuerttemberg ein Pilotprojekt begonnen. Ziel dieses Vorprojektes war die Entwicklung und Erprobung einer Grosskammer zur Untersuchung von Filterwirkung, Wintertauglichkeit und Kammerklima. Solche 'oben offenen Experimentierkammern' bieten die Moeglichkeit, Luftschadstoffe der Umgebungsluft auszuschliessen. Aus den Kontrollen mit den jeweiligen Freiluftbaeumen lassen sich dann Rueckschluesse auf die Auswirkungen der verschiedenen Schadstoffe ziehen. Dieses Pilotprojekt wurde im Muenstertal im Suedschwarzwald in 850 m ue NN durchgefuehrt. Die praktische Erprobung waehrend zweier Betriebsjahre zeigte einen weitgehend stoerungsfreien Kammerbetrieb. Die hoelzerne Konstruktion und die Folienbespannung widerstanden allen Belastungen durch Wind und Schnee. Lueftungs- und Filterungssystem arbeiteten befriedigend. Im Gegensatz zum technischen Kammerbetrieb bleiben die qualitativen Kammerbedingungen hinter den Erfordernissen zurueck. Eine wesentliche Abweichung von den Freilandbedingungen stellten die fehlenden Nebel- und Tauereignisse dar. Aus immissionsoekologischer Sicht entfielen hierdurch Depositionen, die fuer das aktuelle Schadensphaenomen der montanen Nadelvergilbung von besonderer Bedeutung sein koennten. Die nahezu lueckenlosen Messreihen der Klimawerte belegten ferner, dass die grundlegende Forderung nach einem freilandaehnlichen Kammerklima in den getesteten Kammern nur bedingt erfuellt werden konnte. Dies traf insbesondere fuer Luft- und Bodentemperaturen, fuer die relative Luftfeuchtigkeit und die Strahlungsverhaeltnisse zu. Aufgrund der beobachteten Klimaeffekte sowie des Fehlens wesentlicher immissionsoekologischer Feuchtefaktoren lassen die Testpflanzen sowohl kurz- als auch langfristig Wuchs- und Symptomreaktionen erwarten, die nicht mit denen des Freilandes vergleichbar sind. Unter diesen Bedingungen ist nur der Vergleich von Kammer zu Kammer statthaft. Die Durchfuehrung spezieller Kurzzeitexperimente (zB waehrend einer Vegetationsperiode) mit den Behandlungsvarianten Rein- und Umgebungsluft scheiterte an der relativ geringen Luftschadstoffbelastung des Projektstandortes. Gegen Langzeit-Experimente sprachen die nicht vergleichbaren Wachstumgsbedingungen innerhalb und ausserhalb der Kammern. Um uebertragbare Kammerergebnisse zu erzielen, muessten kostenintensive Optimierungsmassnahmen vorgenommen werden. Vorrangige Verbesserungen waeren im Bereich der Lichtbedingungen und der Temperaturreduktion angezeigt. Die Steuerungsgruppe kam zu dem abschliessenden Ergebnis, dass das Projekt im Vorprojektstadium abgeschlossen und am Standort 'Muenstertal' nicht in ein langfristiges Abschlussprojekt uebergeleitet werden sollte.

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.

Forschergruppe (FOR) 5438: Der urbane Einfluss auf dem mongolischen Plateau: Verflechtungen von Stadtwesen, Wirtschaft und Umwelt, Sub project: Virtual Landscape and Multispectral Survey

The project is a subproject of the proposed research group "Urban impacts on the Mongolian Plateau - Entanglements of Economy, City, and Environment". The project part presented here has the task to document the landscape to be investigated by the research group by means of a large-scale aerial survey with different sensors in order to create a highly accurate data basis for further investigations. The first goal of our project is the large-scale, high-resolution and high-precision documentation of the archaeological landscape in order to provide the participating archaeologists with 3D models, orthoimages and digital surface models. For this purpose, a so-called fixed-wing drone will be used, which, with its long range and flight duration, allows the recording of areas up to one square kilometer in size in a single mission. At the same time, the areas will be imaged with a multispectral camera, which covers the near-infrared range in addition to visible light. From the resulting images, vegetation indices can be calculated that clearly show the differences in the vitality of plants. In this way, it is possible to identify subterranean archaeological structures based on vegetation characteristics that would otherwise remain hidden to the human eye. Especially the open steppe landscape of Mongolia with its low and homogenous vegetation seems to be predestined for such an investigation. In a third step, the generated data will be compared with the results of the geophysical prospection to find out which features and structures can be best identified in which data sets and how they differ. For this purpose, an integrated GIS database system is implemented, which guarantees the integration of the data and the joint analysis. From this, a feature catalog will be developed that shows the specific archaeological structures appearing in the different datasets to serve as a basis for subsequent and comparable projects.

Impact of elevated nitrogen inut on the biogeochemistry and productivity of tropical forests (NITROF) - Effects of enhanced N deposition on productivity and structure of a tropical montane rainforest in Panama

Nitrogen deposition in tropical areas is projected to increase rapidly in the next decades due to increase in N fertilizer use, fossil fuel consumption and biomass burning. As tropical forest ecosystems cover about 17 percent of the land surface and are responsible for about 40 percent of net primary production, even small changes in N (and consequently C) cycling can have global consequences. Until now studies an consequences of enhanced N input in tropical forest ecosystems have been very limited and even very rarely addressed its deleterious effects to the environment. There is undoubtedly a huge discrepancy between the expected increase in N deposition in the tropics and the present knowledge an how tropical forest ecosystems will react to this extra input of reactive N. Our research aims at quantifying the changes in processes of N retention (plant growth, biotic and abiotic N immobilization in the soil) and losses (gaseous N losses, nitrification, denitrification, leaching of different forms of dissolved N). Implementation of policy and management tools, like the international trading of carbon credits under the Kyoto Protocol, need researches that allow us to better understand the consequences of environmental change (N deposition) an forest productivity. Our research will have important implications for predicting future responses of forest C cycle to changes in N deposition, and for the role of N deposition in tropical forests to affect potential feedback mechanisms of CO2 fertilization and climate change.

Sonderforschungsbereich (SFB) 1357: MIKROPLASTIK - Gesetzmäßigkeiten der Bildung, des Transports, des physikalisch-chemischen Verhaltens sowie der biologischen Effekte: Von Modell- zu komplexen Systemen als Grundlage neuer Lösungsansätze; MICROPLASTICS - Understanding the mechanisms and processes of biological effects, transport and formation: From model to complex systems as a basis for new solut, Sonderforschungsbereich (SFB) 1357: MIKROPLASTIK - Gesetzmäßigkeiten der Bildung, des Transports, des physikalisch-chemischen Verhaltens sowie der biologischen Effekte: Von Modell- zu komplexen Systemen als Grundlage neuer Lösungsansätze

Die ubiquitäre Kontamination der Umwelt durch Mikroplastik (MP), die damit verbundenen potenziellen Risiken für Ökosysteme und letztendlich für unsere Gesundheit ist in letzter Zeit sehr stark in den Blickpunkt des öffentlichen und wissenschaftlichen Interesses gerückt. Das junge Forschungsfeld MP hat sich bis dato vorwiegend auf die Entwicklung geeigneter Monitoringverfahren, auf die quantitative Abschätzung der Kontamination der Umwelt, auf die Identifikation relevanter Eintragspfade und auf erste Eintragsminimierungsansätze beschränkt. Ökotoxikologische Fragestellungen wurden zumeist mit Hilfe fabrikneuer Kunststoffe untersucht. Bei all diesen Ansätzen fehlte jedoch bislang ein fundamentales Verständnis von den physikalischen, chemischen und biologischen Prozessen, denen MP in der Umwelt unterworfen ist. Die wissenschaftliche Komplexität der Thematik MP erfordert für ein ebensolches Verständnis jedoch einen interdisziplinären Ansatz, der die traditionellen Fachgrenzen überbrückt. Das Ziel dieser SFB-Initiative ist es daher - ausgehend von Modellsystemen für Kunststoffe, Organismen und Umweltkompartimente - ein grundlegendes Verständnis jener Prozesse und Mechanismen zu erlangen, die in Abhängigkeit von den physikalischen und chemischen Eigenschaften der Kunststoffe (A) die biologische Effekte von MP in limnischen und terrestrischen Ökosystemen bedingen, (B) die Migrationsbewegungen der MP-Partikel in und zwischen Umweltkompartimenten beeinflussen sowie (C) die Bildung von MP ausgehend von makroskopischen Kunststoffen verursachen. Diese Erkenntnisse werden erstmals eine wissenschaftlich fundierte Grundlage für die Bewertung der Umweltrisiken von MP existierender Massenkunststoffe bieten. Darauf aufbauend sollen - bereits in der ersten Antragsphase beginnend - neue umweltfreundliche Kunststoffe im Sinne einer nachhaltigen Polymerchemie entwickelt und anhand von Modellsystemen verifiziert werden. Diese neuen Kunststoffe werden unter anderem schnellere Abbauprozesse durch die Applikation von Beschleunigern und strukturellen Modifikationen aufweisen und werden zur Vermeidung bzw. Reduzierung von MP beitragen. Aufgrund der gewonnenen umfassenden Erkenntnisse aus Phase I sollen zudem auf längere Sicht (Phase II und III) Kunststoffe gezielt so modifiziert werden, dass sie aufgrund ihrer neuen Eigenschaften keine schädigenden Effekte auf Organismen und auf die Umwelt insgesamt mehr aufweisen. Die Komplexität der untersuchten Modellsysteme soll im Verlauf des SFB 1357 gesteigert werden, um eine möglichst hohe Relevanz in Bezug auf reale Ökosysteme zu erreichen.

Revitalisierung der Liesing - Auswirkung von Massnahmen zur Abwasserreinigung

Im Rahmen einer interdisziplinaeren Arbeitsgruppe sollen die unterschiedlichen Massnahmen auf dem Gebiet der Abwasserreinigung auf die Gewaesserguete der Liesing beurteilt werden. Neben den Vorbelastungen aus Niederoesterreich sollen die derzeit noch bestehenden Einleitungen in Wien abgeschaetzt werden. Die Auswirkungen der Einleitung der Klaeranlage Blumental mit unterschiedlichen Reinigungsanforderungen (Nitrifikation, Denitrifikation, P-Entfernung, Filtration) stellen die zentrale Aufgabe des Forschungsprojektes dar.

BBS: Developing methods to simulate biome boundary shifts

Frame: The project is part of the GLP (Global land project) fast track action (http://bbs2008.wikidot.com) Decreasing uncertainty in predicting biome boundary shifts which aims at improving the simulation of biome boundary shifts at large spatial scales, working group Migration . The long-term goal is to improve existing vegetation models or to develop new models that are reliable and robust and can be included in Earth System models for studying biosphere-atmosphere feedbacks. Rationale: Because of the nature of terrestrial plant population and community dynamics and dispersal, and the pace of climate change, predicting the future distribution of plant species is challenging. Many coupled GCM's assume simply that the boundaries between major terrestrial biomes are either static, or adjusted non-mechanistically to follow the change of climate without time lags. In some DGVM's, a non-mechanistic treatment of biome boundaries is employed with assumed delays. Recent model simulations with both explicit seed dispersal and population and community dynamics suggest that range shifts of forest biomes will be both complex and extremely delayed (several millennia delay for centennial warming). Research topics: the effect of plant population processes and dispersal on migration, the effect of spatial heterogeneity (e.g. fragmentation or barriers) on dispersal and migration, methods to incorporate these effects into large scale models like such as DGVM's, the lags due to species migration and their effects on feedbacks to the earth system. Methods: Starting from the forest landscape model TreeMig which describes tree species migration by explicitly simulating seed dispersal on a grid of 1km wide cells, we develop numerical approaches to describe migration across heterogenous grid cells. These approaches are either aggregated models of within-cell migration speed, e.g. derived from meta-modelling, or simulating spread in a subset of smaller cells within each grid cell and then extrapolating to the larger cell. We test our methods with simulations on south-north transects in Siberia and assess the effect of species migration on the feedbacks to the earth system.

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.

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.

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