Uniform bathymetric zonation of marine benthos on a Pan-Arctic scale

While numerous regional studies of bathymetric zonation of benthic fauna globally have been done, few large-scale analyses exist, and no ocean-scale studies have focused on the Arctic Ocean to date. In the present work we, hence, examined bathymetric zonation of macro- and megabenthos over a depth range spanning from the shelf to the abyssal plain (14 – 5416 m) and regionally extending from the Fram Strait to the Beaufort Sea (as a whole hereafter called the Central Arctic). Based on 104 quantitative (box-corers and grabs) and 37 semi- quantitative (trawls) samples compiled from different studies we evaluated bathymetric zonation patterns in abundance, biomass and diversity, and also compared species composition among samples. Abundance and biomass decreased with depth from > 3000 ind. m−2 and > 40 g ww m−2 to ∼ 130 ind. m−2 and −2 corroborating previous studies. Diversity showed a parabolic pattern, peaking at ∼ 100–600 m. Cluster analysis revealed four (macrofauna) and five (megafauna) groups of benthic assemblages, including three that covered the upper and lower continental slope and the abyssal plains with relatively little overlap (named the Lower Shelf – Upper Slope 1, the Lower Slope and the Abyss). Substantial changes in benthic community composition were observed at depths 650–950 m (between the Lower Shelf – Upper Slope 1 and the Lower Slope) and 2600–3000 m (between the Lower Slope and the Abyss), so we interpreted these two depth horizons as major bathymetric boundaries. The first boundary (650–950 m) corresponds to the transition from sublittoral to bathyal fauna consistent with previous studies. The second boundary (2600–3000 m) reflects a decrease in benthic abundance, biomass and diversity within the Central Arctic abyssal plain. Bathymetric patterns and species overturn of benthos were relatively uniform throughout the entire Central Arctic continental slope and abyssal plain. For some regions of the Arctic Ocean, foremost for the area north from Greenland and Canadian Archipelago, benthic data are still unavailable and further research is needed

Community structure of macrofauna in the deep Fram Strait: A comparison between two bathymetric gradients in ice-covered and ice-free areas

This study compares the macrofaunal communities along two bathymetric transects (1000 – 2500 m water depth) in predominantly ice-covered western (offshore Greenland) and generally ice-free eastern (offshore Svalbard) regions of the Fram Strait. Material was collected using an USNEL 0.25 m2 box corer and all sediment samples were processed through a 500-μm sieve. A total of 1671 organisms from 169 species were found. Densities off Greenland were generally lower than those observed off Svalbard. On both sides of the Fram Strait, density, biomass and biodiversity generally decreased with increasing water depth. An exception was observed at the deepest station off Greenland (2500 m water depth), which was located within the Marginal Ice Zone. At this station, macrofaunal density was elevated (992 ± 281 ind. m−2) compared to the adjacent shallower sampling areas off Greenland (272 ± 208 ind. m−2 to 787 ± 172 ind. m−2) and the deeper stations (2000 and 2500 m water depth) off Svalbard (552 ± 155 ind. m−2 and 756 ± 182 ind. m−2). The most abundant species along both transects was the polychaete Galathowenia fragilis (off Greenland: 288 ind. m−2, off Svalbard: 740 ind. m−2). Sea ice coverage and water depth, as well as the associated food availability at the seafloor, seem to be crucial factors driving the macrofaunal community patterns. A strong pelago-benthic coupling is observed to be typical in Arctic deep-sea ecosystems, and is also confirmed by our study

"Wissenschaft fürs Wohnzimmer" – two years of interactive, scientific livestreams weekly on YouTube

Science communication is becoming increasingly important to connect academia and society, and to counteract fake news among climate change deniers. Online video platforms, such as YouTube, offer great potential for low-threshold communication of scientific knowledge to the general public. In April 2020 a diverse group of researchers from the Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research launched the YouTube channel "Wissenschaft fürs Wohnzimmer" (translated to "Sitting Room Science") to stream scientific talks about climate change and biodiversity every Thursday evening. Here we report on the numbers and diversity of content, viewers, and presenters from 2 years and 100 episodes of weekly livestreams. Presented topics encompass all areas of polar research, social issues related to climate change, and new technologies to deal with the changing world and climate ahead. We show that constant engagement by a group of co-hosts, and presenters from all topics, career stages, and genders enable a continuous growth of views and subscriptions, i.e. impact. After 783 days the channel gained 30,251 views and 828 subscribers and hosted well-known scientists while enabling especially early career researchers to improve their outreach and media skills. We show that interactive and science-related videos, both live and on-demand, within a pleasant atmosphere, can be produced voluntarily while maintaining high quality. We further discuss challenges and possible improvements for the future. Our experiences may help other researchers to conduct meaningful scientific outreach and to push borders of existing formats with the overall aim of developing a better understanding of climate change and our planet

Bacterial microbiota on circulating Colombian banknotes

RESUMEN: Diariamente los seres humanos están en interacción con objetos de uso continuo, como el papel moneda, sin el conocimiento de que estos almacenan microorganismos y de que nos exponemos al contacto con potenciales patógenos. La composición de la comunidad bacteriana en un billete colombiano fue determinada mediante el secuenciamiento profundo de librerías de amplicones 16S. Se encontraron 233 géneros bacterianos; 12 de estos géneros corresponden a especies con potencial patogénico. El género más abundante fue Propionibacterium, seguido de Streptococcus, Staphylococcus y Pseudomonas. Este es el primer reporte de la diversidad bacteriana que puede ser alojada en este objeto de alta circulación en Colombia. Pocos estudios en el mundo han mostrado este nivel de detalle de la microbiota en billetes de circulación y ofrece un panorama mucho más amplio de la exposición diaria a microorganismos al utilizar papel moneda en las condiciones en las que se utiliza en Colombia.ABSTRACT: Commonly used objects such as currency paper can be colonised by bacteria and can serve as carriers of microbes. This colonisation might expose us to unnoticed pathogenic bacteria. In this study, the researchers obtained a detailed panorama of the microbes that can be carried on currency notes in Colombia by using 454 next-generation deep sequencing of 16S amplicón libraries. A total of 233 bacterial genera were detected and classified, 12 of which are potential human pathogens. The most abundant genera were Propionibacterium, Streptococcus, Staphylococcus and Pseudomonas. To date, this is the first in-depth analysis ofthe microbiota carried by circulating banknotes in our continent and it offers insights into dailyexposure to microbes when using banknotes in Colombia

Amine–Borane Dehydropolymerization : Challenges and Opportunities

The dehydropolymerization of amine–boranes, exemplified as H2RB⋅NR′H2, to produce polyaminoboranes (HRBNR′H)n that are inorganic analogues of polyolefins with alternating main-chain B−N units, is an area with significant potential, stemming from both fundamental (mechanism, catalyst development, main-group hetero-cross-coupling) and technological (new polymeric materials) opportunities. This Concept article outlines recent advances in the field, covering catalyst development and performance, current mechanistic models, and alternative non-catalytic routes for polymer production. The substrate scope, polymer properties and applications of these exciting materials are also outlined. Challenges and opportunities in the field are suggested, as a way of providing focus for future investigations

LTER HAUSGARTEN 2018 - Long-Term Ecological Research in the Fram Strait, Cruise No. MSM77, September 15 - October 13, 2018, Longyearbyen (Svalbard) - Edinburgh (Scotland)

The 77th cruise of the RV MARIA S. MERIAN contributed to various large national and international research and infrastructure projects (FRAM, ARCHES, INTAROS, ICOS, SIOS) as well as to the research programme PACES-II (Polar Regions and Coasts in the changing Earth System) of the Alfred-Wegener-Institute Helmholtz-Center for Polar and Marine Research (AWI). Investigations within Work Package 4 (Arctic sea ice and its interaction with ocean and ecosystems) of the PACES-II programme, aim at assessing and quantifying ecosystem changes from surface waters to the deep ocean in response to the retreating sea ice, and at exploring the most important (feedback) processes determining temporal and spatial variability. Contributions to the PACES-II Work Package 6 (Large scale variability and change in polar benthic biota and ecosystem functions) include the identification of spatial patterns and temporal trends in relevant benthic community functions, and the development of a comprehensive science community reference collection of observational data. Work carried out within WPs 4 and 6 will support the time-series studies at the LTER (Long-Term Ecological Research) observatory HAUSGARTEN (Fig. 1.1), where we document Global Change induced environmental variations on a polar deep-water ecosystem. This work is carried out in close co-operation between the HGF-MPG Joint Research Group on Deep-Sea Ecology and Technology and the PEBCAO Group (Phytoplankton Ecology and Biogeochemistry in the Changing Arctic Ocean) at AWI as well as the working group Microbial Geochemistry at the GEOMAR and the HGF Young Investigators Group SEAPUMP (Seasonal and regional food web interactions with the biological pump)

Welcome to the dark side – Die Tiefsee im Wandel

Unterhalb des lichtdurchfluteten Teil des Meers beginnt sie – die Tiefsee. Nicht nur die Dunkelheit, sondern auch der hohe Druck und ein geringes Nahrungsangebot lassen diesen Ort als lebensfeindlich erscheinen. Doch die Tiefsee ist nicht nur Lebensraum für faszinierende Geschöpfe wie Vampirtintenfische, Asselspinnen oder Schlangensterne. Sie ist auch an zentralen Prozessen wie Nährstoffkreisläufen und Kohlenstoffspeicherung beteiligt. Umweltveränderungen aufgrund des Klimawandels können in der Tiefsee z.B. zu Veränderungen in der Artenvielfalt und den Nährstoffkreisläufen führen. Mit Blick auf die arktischen Tiefseeregionen ist hier die Framstraße zwischen Grönland und Spitzbergen von besonderer Bedeutung. Sie ist die einzige tiefe Wasserstraße zwischen dem nördlichen Atlantik und dem zentralen Arktischen Ozean, wodurch ein Austausch von großen Wassermassen gewährleistet wird. Um die Auswirkungen des Klimawandels in der Framstraße besser zu erforschen, hat das Alfred-Wegner-Institut für Polar- und Meeresforschung (AWI) vor 20 Jahren das HAUSGARTEN Observatorium errichtet. Dauerhaft installierte Messstationen sowie jährliche Untersuchungen vor Ort liefern unerlässliche Daten über Veränderungen durch den Klimawandel – von der Meeresoberfläche bis hin zum Tiefseeboden. Am Beispiel der Framstraße beleuchte ich in diesem Vortrag, welche Folgen der Klimawandel für die arktische Tiefsee hat und warum diese auch direkt den Menschen betreffen

Konzeptionierung einer adaptiven Gebäudehülle mit regelbarer Vakuumdämmung

Wärmedämmungen an Gebäuden sind für den Winterfall essentiell, um den Heizenergiebedarf zu minimieren. Hoch wärmegedämmte Gebäude sind im Sommer jedoch anfällig für Überwärmung, da auch bei niedrigeren Außentemperaturen (z. B. nachts) durch die Wärmedämmung die Transmission von Wärme aus dem Gebäude nach außen minimiert wird. Ideal wäre daher eine bedarfsgerechte Anpassung des Wärmedurchgangs der Gebäudehülle. Deshalb wird in dieser Arbeit eine adaptive Gebäudehülle mit regelbarer Vakuumdämmung konzeptioniert. Dabei soll die Wärmeleitfähigkeit von porösen Vakuumdämmpaneelen durch Einströmen von Wasserstoff erhöht werden. Der Wasserstoff wird in Metallhydridreaktoren gespeichert und bei Bedarf zur Verfügung gestellt. Zur Vermeidung einer ständigen Wärmezufuhr zum Aufrechterhalten des wärmeleitenden Zustandes des Paneels und zur Optimierung der Regelbarkeit wird zwischen Paneel und Reaktor ein Absperrventil eingebaut. In dieser Arbeit werden Anforderungen und mögliche Materialien für die dafür notwendigen Komponenten identifiziert. Anschließend wird ein Versuchsaufbau entwickelt, um die konzeptionierte regelbare Wärmedämmung zu untersuchen. Damit wird die grundsätzliche Funktionalität des konzeptionierten Systems nachgewiesen. Durch den Einbau des Ventils werden deutliche Verbesserungen gegenüber vorliegenden Konzepten bezüglich Regelbarkeit und Energiebedarf sowie kurze Schaltzeiten von ca. 15 Minuten möglich. Darüber hinaus werden weitere Laborversuche zum Verhalten von Reaktor und Paneel durchgeführt. Abschließend wird der weitere Forschungsbedarf zur Erprobung solcher Systeme in Gebäudehüllen ermittelt