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The lake Laacher See (East Eifel, Germany) is affected by eutrophication due to high phosphorous concentration for stagnant waters averaging 34 µg/l (range of 25–40 µg/l P since the year 2000). These elevated concentrations have been monitored since the 1950s and an oligotrophic status could not be achieved despite various measures [2]. A linear correlation was determined between dissolved phosphate (211 – 643 μg/l) and vanadium (6.7 – 28.4 μg/l) in groundwaters of the Ringseitert volcanic complex (West Eifel) with implications for drinking water use [4]. These issues are the motivation to investigate the geogenic input of phosphorous into Laacher See and of vanadium into groundwaters by fluid-rock-interaction.Laacher See is the water-filled crater area of the Plinian-erupted Laacher-See-volcano, which belongs to the East Eifel Volcanic Field with an active volcanism for 0.46 Ma [6]. The catchment of this lake includes rocks of siliciclastic Lower Devonian basement, scoria cones and lava flows of basanitic and tephritic compositions, and phonolithic to foiditic tephra from the Rieden volcanic complex. The youngest volcanic unit is the phonolithic, strong geochemically zoned tephra from the Laacher-See-volcano, which ejected 6 km³ magma in form of pumice and ash 12.9 ka ago [3,6].The dissolution of apatite (primary) and vivianite (secondary phosphate phase) is assumed to be the reason of geogenic input of phosphorous and vanadium by groundwater flow. A particularity of the Laacher See area is the occurrence of mofettes that lead to elevated concentrations of CO2, decreased pH and enhanced apatite dissolution [5]. The hydrochemical modelling program PHREEQC is used to investigate the equilibrium state of phosphate and vanadium in groundwaters at specific Eh/pH-conditions, p(CO2)-values and compositions. In addition, residence times calculated by hydraulic conductivities and dissolution rates from batch experiments are used to distinguish between rate-limited or equilibrium process in phosphate dissolution. Data on phosphorous concentrations and pH of soils in the vicinity of the Laacher See and their equilibrium solutions are evaluated to their geological, geochemical and anthropogenic background and provide clues to phosphorous sources [1].In future studies, bulk rock concentrations will be measured using XRF and total digestion, and detailed dissolution rates will be measured using extended batch experiments to combine these findings into a conceptual hydrogeological model of geogenic phosphate and vanadium input to lake Laacher See.References:[1] Armbruster, M. & Wiesler, F. 2012. Ermittlung der P-Gehalte entlang von 10 Transekten am Laacher See. LUFA Speyer, Speyer. P.24 (unpublished)[2] Block, U. et al. 2015. Übersicht über die Phosphatthematik am Laacher See. Fachhochschule Bingen. P.41[3] Bogaard, P.v.d. & Schmincke, H.U. 1984. The eruptive center of the late quaternary Laacher see tephra. Geologische Rundschau, 73, 933-980, http://doi.org/10.1007/BF01820883.[4] Härter, L.M. et al. 2020. Vorkommen von Vanadium im Grundwasser der Vulkaneifel. Grundwasser, 25, 127-136, http://doi.org/10.1007/s00767-020-00447-x.[5] Pan, H.B. & Darvell, B.W. 2009. Calcium Phosphate Solubility: The Need for Re-Evaluation. Crystal Growth & Design, 9, 639-645, http://doi.org/10.1021/cg801118v.[6] Schmincke, H.-U. 2007. The Quaternary Volcanic Fields of the East and West Eifel (Germany). In: Ritter, J.R.R. & Christensen, U.R. (eds) Mantle Plumes: A Multidisciplinary Approach. Springer Berlin Heidelberg, Berlin, Heidelberg, 241-322, http://doi.org/10.1007/978-3-540-68046-8_8

A recent report has identified 6PPD-quinone as an environmental compound responsible for drastic declines in coho salmon (Oncorhynchus kisutch) populations. As it is derived by oxidation of the preservative 6PPD that is found in tire rubber, this compound is not commercially available for further investigation of its biological properties. This work provides a brief synthesis of the oncorhynchicide 6PPD-quinone that can be used for that purpose.

Atmospheric particulate matter has become a major issue in urban areas from both a health and an environmental perspective. In this context, biomonitoring methods are a potential complement to classical monitoring methods like impactor samplers, being spatially limited due to higher costs. Monitoring using spider webs is compared with the more common moss bag technique in this study, focusing on mass fractions and ratios of elements and the applicability for source identification. Spider webs and moss bags with Hypnum cupressiforme were sampled at the same 15 locations with different types of traffic in the city of Jena, Germany. In the samples, mass fractions of 35 elements, mainly trace metals, were determined using inductively coupled plasma-optical emission spectroscopy (ICP-OES) and inductively coupled plasma-mass spectrometry (ICP-MS) after aqua regia digestion. Significantly higher mass fractions in spider webs than in moss bags were found, even after a much shorter exposure period, and could not be ascribed completely to a diluting effect by the biological material in the samples. Different mechanisms of particle retention by the two materials are therefore assumed. More significant correlations between elements have been found for the spider web dataset. Those patterns allow for an identification of different sources of particulate matter (e.g. geogenic dust, brake wear), while correlations between elements in the moss bags show a rather general anthropogenic influence. Therefore, it is recommended to use spider webs for the short-term detection of local sources while moss bag biomonitoring is a good tool to show a broader, long-term anthropogenic influence.

Elevated levels of particulate matter (PM) in urban atmospheres are one of the major environmental challenges of the Anthropocene. To effectively lower those levels, identification and quantification of sources of PM is required. Biomonitoring methods are helpful tools to tackle this problem but have not been fully established yet. An example is the sampling and subsequent analysis of spider webs to whose adhesive surface dust particles can attach. For a methodical inspection, webs of orb-weaving spiders were sampled repeatedly from 2016 to 2018 at 22 locations in the city of Jena, Germany. Contents of Ag, Al, As, B, Ba, Ca, Cd, Co, Cr, Cs, Cu, Fe, K, La, Li, Mg, Mn, Mo, Na, Ni, P, Pb, Rb, S, Sb, Si, Sn, Sr, Th, Ti, V, Y, Zn and Zr were determined in the samples using inductively coupled plasma-mass spectrometry (ICP-MS) and inductively coupled plasma-optical emission spectroscopy (ICP-OES) after aqua regia digestion. Multivariate statistical methods were applied for a detailed evaluation. A combination of cluster analysis and principal component analysis allows for the clear identification of three main sources in the study area: brake wear from car traffic, abrasion of tram/train tracks and particles of geogenic origin. Quantitative source contributions reveal that high amounts of most of the metals are derived from a combination of brake wear and geogenic particles, the latter of which are likely resuspended by moving vehicles. This emphasizes the importance of non-exhaust particles connected to road traffic. Once a source identification has been performed for an area of interest, classification models can be applied to assess air quality for further samples from within the whole study area, offering a tool for air quality assessment. The general validity of this approach is demonstrated using samples from other locations.

Differentiating between regularly seasonal, irregular and event-based clastic sedimentation is difficult if sedimentation structures resemble and dating methods are imprecise. In this study - clastic light and dark laminae from lava-dammed Paleolake Alf in the Late Pleistocene in the Quaternary West Eifel Volcanic Field are analyzed to clarify how they formed and if they are of annual origin and comparable to assumed periglacial varves from neighboring Lake Holzmaar. Therefore, a multiproxy approach is applied combining sediment thin section analysis which focuses on composition and structure with 14C dates. The results are compared to recently-formed annually-laminated clastic sediments of, e.g., the High Canadian Arctic. Observed sedimentation structures reveal sediment delivery by over- and interflows and deposition from suspension forming two characteristic microfacies: Type I graded laminae and Type II laminae with graded sublayers. Additionally, erosional bases and event deposits indicate episodic underflows. Thus, lamination is potentially seasonal but is significantly veiled by extreme runoff causing erosion and resuspension processes or a mixed water body preventing sediment delivery into the lake basin. However, sedimentation processes between watershed and lake could be reconstructed by comparing recent and paleosediment structures.

Maar eruptions form small initially steep-walled basins that contain important archives for the climatic and palaeoenvironmental history in continental areas. The two Ukinrek Maars in south-western Alaska erupted between 30 March and 9 April 1977 and are the best-documented maars that have erupted in historical time. This study presents a preliminary analysis of geomorphology, hydrology, magnetic susceptibility, geochemistry and sedimentology data of a field study in August 2004. These results, photographs and topographic surveys are combined for reconstructing the post-eruptive evolution of Ukinrek East Maar. Within less than 30 years the initially polygonal shape of the crater with nearly vertical crater walls has developed into an almost elliptic form with slopes of 35° inclination on debris fans between a few escarpments. The water table and the crater floor have risen significantly and the crater diameter:depth ratio increased from 3·4 to 5·7, whereas the average height of the crater rim remained almost constant. The main sub-aerial resedimentation process is formation of rock falls, rock slumps and scree resulting in debris flows and turbidites within the lake that is ice-covered throughout about half of the year. Distal lake sediments consist of laminated minerogenic clayey-sandy silts that document frequent turbidity currents. From the linear sedimentation rate of only ca 5 mm year−1 in 17 cm long cores it may be concluded that the largest portion of the crater sediments formed within the first few months of the maar history, however, this has to be confirmed by future studies.

Spatial distribution of magnetic susceptibility and the gravel fraction in surface sediments in the Atlantic sector of the Southern Ocean were investigated to reconstruct source areas and recent transport pathways of magnetominerals and ice-rafted debris. Maxima of magnetic susceptibility were observed offshore from areas where mafic source rocks occur, e.g. Queen Maud Land and the northern Antarctic Peninsula. The glacigenic input of debris and subsequent redeposition of fine material by bottom and turbidity currents on the continental margins result in regional variations of the gravel and susceptibility values. In the deep sea, however, the mixing of ice-rafted debris and turbidites from distal source areas causes a homogenous distribution of the susceptibility signal. On submarine elevations such as Maud Rise and Astrid Ridge, dust input may be an additional source for magnetominerals.

Magnetic susceptibility and ice-rafted debris of surface sediments in the Nordic Seas were investigated to reconstruct source areas and recent transport pathways of magnetic minerals. From the distribution of magnetic susceptibility and ice-rafted debris and published data on petrographic tracers for iceberg drift, we reconstructed a counter-clockwise iceberg drift pattern during cooler phases in the Holocene, which is similar to conceptual and numerical models for Weichselian iceberg drift. The release of basaltic debris at Scoresby Sund played a significant role for the magnetic signature of stadial/interstadial events during isotope stage 3 recorded in sediment cores of the Nordic Seas.

Terrigenous sediment parameters in modern sea-bottom samples and sediment cores of the South Atlantic are used to infer variations in detrital sources and modes of terrigenous sediment supply in response to environmental changes through the late Quaternary climate cycles. Mass-accumulation rates of terrigenous sediment and fluxes of ice-rafted detritus are discussed in terms of temporal variations in detrital sediment input from land to sea. Grain-size parameters of terrigenous mud document the intensity of bottom-water circulation, whereas clay-mineral assemblages constrain the sources and marine transport routes of suspended fine-grained particulates, controlled by the modes of sediment input and patterns of ocean circulation. The results suggest low-frequency East Antarctic ice dynamics with dominant 100-kyr cycles and high rates of Antarctic Bottom Water formation and iceberg discharge during interglacial times. In contrast, the more subpolar ice masses of the Antarctic Peninsula also respond to short-term climate variability with maximum iceberg discharges during glacial terminations related to the rapid disintegration of advanced ice masses. In the northern Scotia Sea, increased sediment supply from southern South America points to extended ice masses in Patagonia during glacial times. In the southeastern South Atlantic, changes in regional ocean circulation are linked to global thermohaline ocean circulation and are in phase with northern-hemispheric processes of ice build-up and associated formation of North Atlantic Deep Water, which decreased during glacial times and permitted a wider extension of southern-source water masses in the study area.