bluuebunny/crossref_metadata_2025 huggingface dataset:
Coastal dune ecogeomorphic states regulated by extrinsic factors
Authors: Costas Susana , Gallego-Fernández Juan B. , Bon de Sousa Luisa , Kombiadou Katerina
Published: February 2023

Coastal dunes result from multiple interactions between biotic and abiotic factors. The complexity of the resultant dune ecogeomorphology will therefore be determined by the spatial and temporal variability of the involved factors and their interactions. This work explores the longshore variability of morphological features, plant community distribution and accumulation patterns of a dune segment (1.4 km-long) located at the downdrift end of a sandy peninsula in the Ria Formosa, Portugal. To understand the main drivers of the observed variability and the implications for dune morphological response, this information was combined with recent multidecadal shoreline evolution data (i.e., 60 years). The integrated results document significant differences in dune morphology, sedimentation patterns and plant zonation, with two distinct dune configurations or states identified in close proximity. One (western sector) shows a narrower dune system, vegetation cover characterised by pioneer species with low densities, and squeezed plant zonation. Conversely, the other (eastern sector) presents a wider dune system with a new foredune, a more developed plant zonation and relatively high vegetation density. Both states could be partially explained by the recent shoreline trends and inlet shifts, with stable to retreating trends in the western sector and shoreline progradation in the eastern one. Plant zonation and accumulation patterns suggest that the dune along the retreating sector is in a cycle of inland migration, encouraged by the reduced accommodation space and the low retention capacity of the vegetation across the dune stoss. Alternatively, observations along the prograding sector suggest that the greater accommodation space and the stabilising feedback between vegetation and topography promoted the seaward progradation of the system and the development of an incipient foredune. Outcomes support the importance of biogeomorphic feedbacks for the dune configuration. However, they also evidence that the role of vegetation within this feedback is rather passive and primarily regulated by physical factors, including regional (low precipitation and sediment transport potentials) and local conditions (e.g., variations in the sediment supply alongshore). Therefore, despite the undeniable role of vegetation in reinforcing dune topography, it is worth highlighting that local external forces may dominate dune response, inhibiting, allowing or reinforcing ecogeomorphic interactions in the long-term.This work is supported by projects 2022.05392.PTDC and PTDC/CTA-GFI/28949/2017, funded by the Portuguese Foundation for Science and Technology.
Vineyard carbon balance: assessing the perspective for carbon farming through long-term eddy covariance measurements
Authors: Pitacco Andrea , Tezza Luca , Ghiglieno Isabella , Vendrame Nadia
Published: February 2023

Vegetation plays an important role in the global carbon budget, absorbing from the atmosphere about 29% of CO2 anthropogenic emissions. Today, forest ecosystems are recognized as carbon sink, while agricultural lands are not taken into account. This is due to the rapid turnover of the carbon assimilated by crops. Indeed, their biomass is removed for food production and the residues and soil organic matter are rapidly degraded due to deep and frequent soil cultivation. However, woody crops like vineyards present biological, structural, and management peculiarities, such as perennial structure, abundant pruning debris, limited soil disturbance, and vegetation cover of the alleys, which could potentially lead to the sequestration of a significant amount of CO2. Recently, several initiatives started to exploit the sequestration potential of agriculture, to reach the targets of Paris agreement (“4 per mille”, Carbon Farming…), but means, rules, and realistic assessment of sequestration potential are still lacking, exposing these proposals to substantial criticism. Eddy covariance technique, as implemented in coordinate networks, can be a powerful tool to proof this important environmental role of agriculture.In order to asses the carbon balance of woody crops on a multi-annual scale, in 2015 we deployed an eddy covariance station in a vineyard located in the Franciacorta area (Northern Italy). The analysis of five years of measurements (2017-2021) shows a consistent pattern over this period with the vineyard acting as carbon sink on annual basis. The net CO2 uptake varied among the years, due to different environmental conditions, but on average it was around 200 gC m-2 y-1. This amount, considerable for an agricultural ecosystem, can represents an important base to quantify the role of viticulture in the perspective of carbon farming initiatives. Even if it can be objected that this sink may be only temporary and the built-up can be substantially disrupted at the end of the vineyard life cycle, these results show that there is a concrete possibility of storing carbon in agricultural soils. Thus, vineyards seem to be good candidates for carbon farming. Proper practices can be defined to preserve this storage at best, greatly contributing to the global carbon budget and boost the role of agriculture in climate change mitigation initiatives.
Define optimum carbon levels in soils in view of multiple soil functions
Authors: Ros Gerard , van den Dool Kees , De Vries Wim
Published: February 2023

Soil organic matter (SOM) content is key for a healthy and high-quality agricultural soil and drives soil processes controlling both crop yield and environmental losses. An increase in soil organic matter or carbon (SOC) levels is seen, both by many conventional farmers and by policy makers, as a desirable objective. Better plant nutrition due to retention of nutrients (N, P, S, micronutrients), ease of cultivation, penetration and seedbed preparation, greater aggregate stability, reduced bulk density, improved water holding capacity and enhanced porosity have all been associated with increased amounts of SOC. A critical threshold for SOC below which the soil becomes less fertile and sustainable is however missing. Consideration of such critical levels involves assessment of the quantitative evidence, i.e. the nature of SOM and the properties it confers on soils, whether justifiable limits can be set for a range of soil types, climatic conditions, or land management/cropping practices and, finally, whether there are any dis-benefits from an increase in SOM levels in soils. Using quantitative relationships derived from literature we assessed the contribution of SOC to the aforementioned soil functions and properties, and linked this contribution to critical targets for the soil functions evaluated. Using this we derived an optimum SOC range for agricultural soils and we illustrate the potential benefits of changes in SOC for most common agricultural systems across Europe. 
A segment model for surface rupture scenarios in the eastern Rhine Graben Boundary fault (Upper Rhine Graben, Germany)
Authors: Pena-Castellnou Sara , Baize Stéphane , Hürtgen Jochen , Reicherter Klaus
Published: February 2023

The eastern Rhine Graben Boundary fault (eastern RGBF) constitutes the eastern margin of the Upper Rhine Graben (URG), the most seismically active area in the plate interiors of Europe. Our recent paleoseismic studies have revealed Late Pleistocene-Holocene surface-rupturing paleoearthquakes with magnitudes M 6–6.5 and cumulative surface displacements in the order of 1–1.2 m vertically and 4–6 m horizontally. Based on the empirical relationships of Wells and Coppersmith, these parameters suggest that the plausible rupture scenarios of those paleoearthquakes are linked to shorter fault segments within the 300 km long eastern RGBF rather than an entire rupture of the fault. Up to date, segmentation on faults of the URG has yet to be evaluated. We aim to define fault segments within the eastern RGBF and their relative tectonic activity to understand how deformation is distributed along the marginal faults and within the graben. To achieve this, we integrate seismicity data, morphotectonic observations (from SRTM, TanDEM-X and LiDAR-based DEMs), geology (Plio-Pleistocene sediment thickness), and interpretation of commercial seismic lines.We define up to seven segments of varying lengths based on geometric and structural fault trace discontinuities (bend, gaps, and changes in strike and dip) and the occurrence and degradation state of tectonic landforms (triangular facets, beheaded channels, hanging valleys and offset alluvial fans), which we also take into account to define the relative level of tectonic activity at each segment. The most active segments are the South-Kraichgau and Freiburg segments, with potential magnitudes of M 7–7.5 (including the historical M 6.7 Basel eq of 1356). The northern area, comprising the Frankfurt-Darmstadt and Odenwald segments, constitute presently a seismic gap with quiescence in historical and instrumental seismicity but with tectonic expression in the landscape and thickest Late Tertiary-Pleistocene deposits, suggesting a potential hazard. Our results provide a basis to propose plausible rupture scenarios for the eastern RGBF for future PSHA studies.
Bioleaching by endophytic microorganisms as a method of element recovery from sewage sludge incineration ash
Authors: Jarosz Kinga , Kasina Monika , Rozpądek Piotr , Ważny Rafał
Published: February 2023

 
Bioleaching by endophytic microorganisms as a method of element recovery from sewage sludge incineration ash 

Incinerated sewage sludge ash (ISSA) has been proven to have resource potential, and in case of some elements, such as phosphorus, in the same concentration range as currently exploited ores. Usage of waste resources, such as ISSA, to recover valuable elements together with the efficient methods are main assumption for sustainable development. Alongside feasibility, economic, energetic and environmental cost of methods applied have to be taken into consideration.  

The effective alternative methods to chemical treatment to recover elements form ISSA that simultaneously lower the negative impact of chemical reagents are biological methods. Microorganisms based solutions, even though described, have still underexplored potential in the field of element recovery. One of the reasons for this state is a limited range of species of microorganisms used for this purpose up to date.  

In present study bacteria and fungi, capable of phosphorus and metal containing phase solubilization, were employed in bioleaching of ISSA. microorganisms have been shown to be both effective in compound transformation as well as resilient in high pH environment – characteristic for ISSA water mixtures. The course and efficiency of bioleaching was determined by the means of ICP methods. The chemical composition of ISSA, leachates, and the post-reaction residues were examined. Moreover, direct observation of interactions between the fungi and the ash was made by SEM-EDS. 

Apart from element recovery, both in case of use of ISSA for fertilization or for any other use (e.g. as an additive to cement), the toxicity of the ash must be examined and reduced.  

The course and effect of ISSA bioleaching by microorganisms was described. The study confirmed that phosphorus extraction as well as chemical neutralization of ash can be achieved using microorganism based bioleaching methods. 

Acknowledgments:  

This publication has been funded from the Anthropocene Priority Research Area budget under the program "Excellence Initiative – Research University" at the Jagiellonian University”.  

This publication has been financed by Opus 17 Project 2019/33/B/NZ9/01372 
Reponse of precipitation to dynamics in global-storm resolving models
Authors: Ricard Lucile , Nenes Athanasios , Stephan Claudia , Falasca Fabrizio
Published: February 2023

Most climate models show a precipitation increase with warming that is smaller than the increase in moisture, which requires a weakening of the convective mass flux and a slowing of the overturning circulation. In this study we use global-storm resolving models (DYAMOND models) to identify the systematic relationships between the precipitation, the vertical velocity and the overturning circulation in the tropics. The cloud-resolving simulations that are 40-day long in winter allow us to study the dynamical response of precipitation over a wide range of spatial scales. A data reduction and inference method, δ-MAPS, provides an efficient way to reduce the complexity and dimensionality of high-resolution simulations. We use the domains identified in 2d fields of atmosphere mass content of water vapor – interpreted as regions of homogeneous precipitable water – as preferential domains to derive the isentropic distribution of vertical mass transport and the isentropic streamfunction. The isentropic analysis consists in sorting the air parcels in terms of equivalent potential temperature, which offers a simple representation of the convective overturning. A multiscale decomposition allows us to quantify the contribution of the mesoscale circulation in comparison to the large-scale overturning circulation. Finally, the results are compared between the different DYAMOND models to evaluate the intermodel spread. By doing so, we evaluate to what extent the spread in precipitation in model ensemble may arise from the differences in representation of the overturning circulation at different scales.
Interactive understanding of groundwater hydrology and hydrogeology – the iNUX project
Authors: Reimann Thomas , Barthel Roland , Birk Steffen , Fernandez-Garcia Daniel , Chen Zhao
Published: February 2023

Groundwater represents more than 97% of the globally available freshwater resources. Groundwater is situated in geological structures in the subsurface and is therefore not visible, difficult to characterize, and manage. As a consequence, it is often not adequately considered by authorities, the general public – and in education. However, teaching and learning Hydrogeology and Groundwater Management at universities, but also as a part of continuing education training for professionals, is essential to deal with future challenges. For this reason, it is important to use suitable teaching material to improve the understanding of the complex topic of groundwater among these target groups. The recent challenge of the COVID-19 pandemic has increased the demand for digital and remote teaching. An ongoing Erasmus+ cooperation project named iNUX – interactive understanding of groundwater hydrogeology aims to address the need for digital teaching material. The project aims to achieve an interactive and digital learning environment in hydrogeology and groundwater management with a European but also global target of teachers and students.
Existing experience in teaching relevant groundwater subjects from highly reputable European universities will be used to develop interactive and digital teaching material focusing on basic and applied hydrogeology. The teaching material will cover basic theory in combination with field and laboratory applications in different European environments (Northern Europe, Central Europe, and the Mediterranean). The teaching material will comprise (1) various types of videos (e.g., field experiments, lab experiments, screencasts of calculations and software use), (2) interactive Jupyter notebooks that combine explanation with live code (e.g., based on Python), (3) various types of questions and problems that allow different assessments to enhance self-controlled learning of students. All materials are intended as open source and publicly available. The iNUX activities also comprise initiatives to establish interest groups to combine efforts towards larger pools of commonly developed digital teaching material (e.g., question pools) and to link with other activities like the 'Groundwater project' (https://gw-project.org/).
The Age of Saturn’s Rings Constrained by the Meteoroid Flux Into the System
Authors: Kempf Sascha , Altobelli Nicolas , Jürgen Schmidt , Cuzzi Jeffrey , Estrada Paul , Srama Ralf
Published: February 2023

The origin of Saturn’s ring is still not known. There is an ongoing argument whether Saturn’s ring have been formed shortly after Saturn together with its satellites or they may actually be a recent phenomenon in the solar system. This possibility of young rings has been vigorously debated for nearly 40 years, since the Voyager flybys of Saturn. Over the years, the most powerful support for this hypothesis has turned out to be the puzzle of the rings’ nearly pure water ice composition – unique in the family of planetary rings – in spite of the constant hail of rocky-carbon meteoroids from outside the Saturn system. However, three major uncertainties have left the ‘young-ring’ hypothesis unproven. Two of these have already been resolved by the Cassini mission: the amount of non-icy material currently in the rings, and the total ring mass. The third main constraint is the mass flux of non-icy meteoroids falling onto the rings. 
Here we report on the measurement of the meteoroid mass flux into the Saturnian system obtained by the charge-sensitive entrance grid system (QP) of the Cosmic Dust Analyser (CDA) on the Cassini spacecraft. The determination mass flux of non-icy material coming into the Saturn system completes the trifecta of constraints that are required to strongly support a youthful ring system. We analyzed the full CDA data set acquired after Cassini’s arrival at Saturn in 2004. The CDA detections determine the incident particle orbits, and they come (surprisingly) not from comets as expected, but mostly from Kuiper Belt Objects (with at least one other population also apparent). This means that most of the particles have low speeds relative to Saturn and are strongly focused gravitationally, such that the flux at the rings is even larger than previously estimated. We have also found that the flux has a statistically significant upper size cutoff, meaning that our detection is robust to Cassini’s finite observation time. 
The impact of vegetation on erosion in the East-African Rift System: New insights from Chew Bahir, southern Ethiopia
Authors: Bookhagen Bodo , Erbello Asfaw , Wittman Hella , Melnick Daniel , Strecker Manfred
Published: February 2023

Past studies indicate that landscape evolution on various timescales is influenced by vegetation cover. However, the linkages between vegetation, type, and species distribution and erosion processes and their relationships between landscape steepness and climate are not well understood. In this study, we focus on the active tectonic setting of the East-African Rift System and its complex climatic and biotic environment to explore linkages between millennial-scale denudation rates and landscape steepness, climate, and vegetation. We specifically focus on spaceborne vegetation-height and biomass measurements that may better reflect the impact of vegetation on geomorphic processes when compared to generally used vegetation cover measurements. We present 12 new in situ 10Be catchment-averaged denudation rates from the tectonically active Chew Bahir area in southern Ethiopia. The sampled catchments comprise a range of denudation rates over one order of magnitude from 0.01 to 0.1 mm/y and largely correlate with rainfall-weighted landscape steepness. We analyze the rates in comparison to previous studies (a) that evaluated the drier central and northern areas of the Kenya Rift to the south of Chew Bahir and (b) that measured denudation rates in the wetter, densely vegetated Rwenzori mountains in Uganda to the west. Rock-strength values between the sites are comparable, although the Rwenzori mountains have undergone rapid Miocene-Pliocene exhumation processes that may have been aided by ubiquitous fractured bedrock. Importantly, we observe a clear impact of biomass on denudation rates. For example, catchments with the same denudation rate and erosional integration timescale but higher biomass can sustain steeper fluvial channels as indicated by their river-steepness indices. We argue that high vegetation heights characterized by deep root structures lead to a stabilization of hillslopes and ultimately allow the formation of steeper channels. This in turn results in lower denudation rates comparable to less vegetated terrain where hillslopes destabilize more rapidly. We analyze the spatial distribution of hillslopes, river-steepness, rainfall, and vegetation biomass within catchments to elucidate their relative impact. This allows us demonstrate the usefulness of vegetation height and biomass measurements for assessing impacts on erosion rates and we explore different weighting schemes for digital elevation model analysis. 
Observation of Possible Kinetic Structures at the Venus Magnetosphere using High Resolution Parker Solar Probe Data
Authors: Sur Dibyendu , Malaspina David
Published: February 2023

Understanding the plasma interactions between induced Venus magnetosphere and solar wind is crucial, especially at the kinetic scale (below the proton Larmor radius). This is because different kinetic-scale electric field structures that are associated with plasma instabilities such as double layers are good indicator of wave-particle energy transfer (Malaspina et al., Geophysical Research Letters, 47, 2020). Structures such as double layers, phase-space holes can emit radio waves (Goodrich and Ergun, The Astrophysical Journal, 809, 2015) or scatter electrons with energy of the order of keV (Vasko et al., Journal of Geophysical Research: Space Physics, 122, 2017). Double layers can create plasma instabilities (Newman et al., Physical Review Letters, 87, 2001), provide heating and acceleration to different particles (Ergun et al., Journal of Geophysical Research: Space Physics, 109, 2004). These structures have already been found in several parts of the earth’s magnetosphere. But due to a lack of high resolution data, observations of these processes are sparse in the magnetospheres of the other planets. The seven encounters that the Parker Solar Probe (PSP) spacecraft will make with Venus’s induced magnetosphere will provide excellent opportunities to measure these processes in this planet. The current talk describes the presence of kinetic-scale electric field structures during the 4th encounter of PSP with Venus’s induced magnetosphere. For this purpose, high resolution electric field data from the PSP FIELDS instrument were used with alongside the FIELDS magnetometer data and data from the Solar Wind Electrons Alphas and Protons (SWEAP) instrument. From these observations, it is found that the PSP passed through Venus’s magnetosheath and tail region during this encounter.  This talk describes the possible presence of plasma double layers when PSP was at the boundary of the magnetosheath region. Phase-space holes are also identified near some of the double layers in this region.
Uniting microbial modelling with microfluidic soil chips
Authors: Hammer Edith , Ohlsson Pelle , Zou Hanbang
Published: February 2023

Empirical soil models reproducing soil characteristics can help to reduce the inherent complexity of soils in experiments. Microengineered or microfluidic soil chips can simulate the soil pore space at microscale in a transparent material that enables direct visual investigation of soil- and soil microbial processes including monitoring of single cells and their interactions in communities. Through the chips it is possible to control and closely monitor microhabitat conditions including oxygen levels and pH, and to single out factors such as spatial relations, pore space structure or resource patch size. They can be designed either close to realistic conditions such as based on µCT measurements, or using simple geometrical patterns that can be frequently replicated and modified within the chip design. They can thus be tailored to fit scenarios of spatially explicit soil computer models and used for iterative in-silico – in-situ experiments. We found amongst others that the geometric shape of a pore space and its connectivity influences bacterial and fungal growth, their interactions and enzymatic activity. We can measure those factors spatially resolved at cellular scale.  We want to initiate a discussion for future collaborations between soil chip experimentalists and computer modelers.
Uncertainty assessment of the array derived rotation measurements
Authors: Rusch Roxanne , Sèbe Olivier , Gaffet Stéphane , Decitre Jean-Baptiste , Lallemand Charly , Boyer Daniel , Cavaillou Alain , Schindele François
Published: February 2023

Analyzing the rotational motions of the seismic wavefield is useful for a multitude of applications ranging from the wavefield decomposition to geological structure estimation or source inversion (Igel et al. 2015, Sollberger et al. 2020). Despite the recent progress in performance (Bernauer et al. 2018), portable rotation sensors are not yet able to measure the seismic background noise in quiet environment. Parallel to the construction of high performance observatory sensors (Igel et al. 2021), several experimentations have shown that seismic rotation motions can be derived from the recordings of classical three translational component (3C) seismometers when arranged in a dense seismic array (Spudich et al. 1995, Suryanto et al. 2006) . Even if these Array Derived Rotation (ADR) measurements can theoretically estimate the seismic rotation background noise, the accuracy of this kind of indirect measurements can be strongly affected by the quality and the variability in the sensors response or installation conditions across the seismic array (Donner et al. 2017).

This work proposes to quantify, as a function of the array aperture and wavefield properties (frequency and wavelength), the uncertainty of the ADR measurements due to uncertainty or lack of detailed knowledge in the precise locations of sensors, orientations and instrumental response, along with the effects of some incoherent disturbing noises across the seismic sensor array. This approach has been applied to the ADR measurements performed with the (3C) dense seismic array deployed at the Low Noise Inter-Disciplinary Underground Science & Technology laboratory (LSBB), Rustrel, France. This analysis shows that a particular attention has to be paid, beyond the standard practices accepted for most seismic arrays, concerning the sensors’ setting up in order to reach uncertainty lower than 10% on the derived rotation measurements.
Biogeochemical dynamics of organic carbon fluxes in intermittent spring catchments
Authors: Feld Annika , Fasching Christina , Reiss Martin , Chifflard Peter
Published: February 2023

Springs represent a direct interface between groundwater and surface water. They can be classified differently with the main distinctions being the spring type and discharge, which mainly influence their biogeochemistry. However, the investigation of organic matter dynamics in springs previously have been neglected due to the assumption of stable conditions, especially in perennial springs. Contrarily, in intermittent springs higher organic carbon (OC) concentrations are expected due to the temporal interruption of the flow regime and therefore longer accumulation rates and residence times of organic matter in the adjacent soil substrate. In the course of climate change, intermittent springs will become more frequent as a consequence of decreasing groundwater levels during dry periods. Dry falling of springs during the year will therefore affect the quantity and quality of OC exports to the adjacent headwater streams.Here we investigate 44 springs in four different study areas in Germany (Sauerland, Rhenish Slate Mountains, Ore Mountains, Black Forest) along a gradient of geology and vegetation type. We complement long-term hydrological instrumentation with quarterly biogeochemical and event-based sampling campaigns. Dissolved and particulate organic carbon concentrations (DOC and POC), composition (via absorbance and fluorescence measurements), stable water isotopes (δ2H, δ18O) and nutrient concentrations (PO4, NO3, NH4) of spring samples and additionally of precipitation, soil water and groundwater samples are analyzed.We aim to unravel seasonal biogeochemical changes, identify drivers of spatial-temporal variability of OC fluxes and to quantify OC export fluxes of springs to the adjacent headwater streams. The results of the first seasonal sampling campaigns point to discharge impacting DOC concentrations and high spatial variability in DOC concentration and composition between the 44 spring sites within the four study catchments.
Soil microbial communities influence plant carbon cost to acquire nutrients
Authors: Lankhorst Jan , Rebel Karin , Odé Astrid , de Boer Hugo
Published: February 2023

Next generation ecosystem models based on a fundamental physiological trait based approach are promising. At leaf level, Eco-Evolutionary Optimality (EEO) approaches are useful as a base for these kinds of models. The tradeoff between the cost of maintaining photosynthetic capacity and the cost of transpiration in different environments can be used effectively and modelled accurately for many different environments. The utility of EEO principles in these models is based on the link between photosynthesis and Gross Primary Production (GPP). Plant available nutrients are one of the largest constraints in ecosystem productivity so recently efforts to include this in EEO theory have been made. A crucial uncertainty in current EEO theory is how the carbon cost to acquire nutrients should be parametrized and to which extend this costs is relatively conservative or changes dynamically under different environmental conditions and between species. We hypothesize that the carbon cost to acquire nutrients increases for a plant grown in a poor soil, requiring more root system to obtain a similar amount of nutrients compared to a plant grown in a rich soil. The effect of soil microbial activity on this cost is less intuitively. Plants grown in reciprocal altruistic symbiosis with mycorrhizal fungi, for example, are known to "trade" carbon for nutrients or water, altering this carbon cost. Soil microbial pathogens can be costly from a plants perspective without any gain, but a generic representation is not yet incorporated in the optimality framework.To test this hypothesis, we conducted a greenhouse pot experiment with two plant species grown in three different nutrient treatments in sand, and compared them to plants of the same species grown in either natural soil or sterilized soil, both without additional nutrient treatment. The plant available nitrogen (N) and phosphorus (P) in the middle nutrient treatment were set to correspond closely to the available nutrients in the natural and sterilized soilsInitial results show a positive correlation between photosynthetic capacity at leaf level and total plant dry weight (DW), both increasing with increasing nutrient availability in sand. In soils however, leaf level photosynthetic capacity and total plant DW react in opposite directions when comparing natural versus sterilized soils. Total plant DW was high in sterilized soils with a relatively low leaf level photosynthetic capacity, while the opposite was found in natural soils. Elemental analyses will be used to (I) analyse carbon allocated to root systems and the correlation with whole plant nitrogen and (I) to extrapolate leaf level photosynthetic capacity to whole plant photosynthetic capacity and examine the relation between plant photsynthetic capacity and total plant DW.Investigating plant carbon allocation under varying soil environments could provide a link between the well formulated leaf level EEO theory and the more cryptic soil influences.
Caprock matters: Surface deformation patterns of salt diapirs using high-resolution Persistent Scatterer Interferometry and geological field observations, Karmostaj and Siah Taq salt diapirs, Zagros mountains, southern Iran
Authors: Rieger Stefanie , Závada Prokop , Bruthans Jiri , Plattner Christina , Brcic Ramon , Zebari Mjahid , Friedrich Anke , Dusingizimana Mugabo
Published: February 2023

Salt diapirs are prominent features in the Zagros fold-and-thrust belt displaying complex interplay between the buoyant forces driving the rock salt to the surface, distribution of the caprock and erosion. The caprock represents the solid residue of salt dissolution in the apical part of the diapir. Understanding the dynamics of subaerial spreading of salt in salt glaciers therefore requires knowledge about the spatiotemporal surface deformation and the underlying controlling factors. However, the contemporary vertical surface-deformation pattern across salt diapirs is difficult to detect and interpret along disciplinary boundaries. Therefore, our goal is to analyse the active surface-deformation patterns of diapir-caprock systems in the Zagros, where diapirs and their caprocks are well exposed and accessible for field mapping. We primarily integrate high-resolution Persistent Scatterer Interferometry (PSI) and field mapping. We used Persistent Scatterer Interferometry (PSI) to obtain the highest available spatiotemporal resolution (on the range of mm/yr, ~12-day repeat cycle) of the vertical surface-deformation pattern across the Karmostaj and Siah Taq salt diapirs for which previous knowledge from detailed geological field mapping is available. Both diapirs contain a thick and deformed caprock layer on top or in the surroundings of the salt cupolas and are located 20 km south from the Lar city in southern Iran. We analysed the PSI-data using Sentinel-1 images acquired between October 2014 and December 2018 using the German Aerospace Center’s (DLR) Integrated Wide Area Processor (IWAP). First, the time-series analysis of the deformation signal in the line-of-sight is investigated for seasonal effects correlations, such as precipitation and heat. Second, the line-of-sight signal is split into vertical and horizontal components. In the next step, geological observations from field mapping provide the context to interpret the geodetic data. Preliminary results indicate that the deformation identified from PSI signal decreases outwards from the apical part for salt diapirs with thick caprock, as the caprocks and other residuals get relatively thicker above the underlying viscous salt. We postulate that the extra load the caprock body exerts on the underlying ductile salt drives subsidence in the crestal portion of the diapir. Understanding the spatiotemporal deformation pattern helps to recognize the impact of dissolution/erosion mechanisms and the distribution of caprock on salt diapirs. Therefore, careful analysis of geodetic signals, which requires contextual integration with geological field observations, reveals the influence of caprock on salt movement.
Changes in dune vegetation trends in the southeastern coast of the Iberian Peninsula
Authors: Lopez-de-la-Nieta Diego , Guisado-Pintado Emilia , Rodríguez-Galiano Víctor F.
Published: February 2023

Coastal dune systems, and its vegetation, serve as a natural buffer against erosion and flooding caused by wave storms and rising sea levels. However, these systems are normally under strong pressures mainly caused by changes in land uses (e.g. tourism or urban development) which in turns could led to a perturbation of the vegetation coverage or the total replacement by hard structures such as promenades. In other coastal areas, however, the vegetation has been proved to undergo an increase in extension and coverage. This effect, known as "greening" (e.g. Jackson et al., 2019), seems to be caused by the combination of changes in climate and atmospheric composition and a reduction in windiness, among others factors. Further, the strong conservation measures carried out in these coastal areas, such as the use of fences and the restoration with autochthonous species, have contributed to this process.This contribution focuses on testing the temporal and spatial change in dune vegetation, coverage and density, in the southeastern Mediterranean coast of Andalusia (Spain). The study site, known as Cabopino (Marbella, Málaga), presents one of the best-preserved Mediterranean coastal dunes (Artola dunes). The coastal-dune system, protected as a Red Natura 2000 site, has undergone little anthropogenic pressures in the past few years. Methodology approach includes a temporal analysis from 2017 to 2022 by calculating NDVI and EVI2 vegetation indexes using the Sentinel-2 MSI (MultiSpectral Instrument) level 2 sensor and Google Earth Engine platform. The dune area was delineated using photointerpretation techniques on the basis of the PNOA orthoimage of 2016 and considering land uses coverage maps and the European Union Habitats - EUR28 (Habitats Directive) of the same year. The NDVI and EVI2 indexes were calculated on composites of images by season (spring, summer, autumn, and winter), using the maximum values of each pixel.Results show that vegetation coverage of the Artola dunes have remained stable during the study period (2017-2022), with small variations in the foredune sector. In terms of vegetation density, NDVI and EVI2 indexes show values of around 0.5-0.6 at the peak of vegetation development (spring and winter) which remains constant from 2017 to 2021. On the contrary, an important decrease in vegetation density is found during the 2022 spring season, with NDVI/EVI2 values of 0.1-0.25. This decrease is coincident with a negative anomaly in winter precipitation in this Mediterranean coastal area.These preliminary results seem to be in line with previous work in the field that support the idea of a global “greening” of coastal dunes because of global (and climatic) change. Nevertheless, vegetation dynamics in Mediterranean coastal dunes seem to be highly controlled by local meteorological conditions, specially to winter precipitation, which ultimate determines vegetation growth and stabilisation.
The WInd VElocity Radar Nephoscope (WIVERN): a candidate mission for the ESA Earth Explorer
Authors: Battaglia Alessandro , Illingworth Anthony , Tridon Frederic , Rizik Ali , Martire Paolo , Scarsi Filippo Emilio
Published: February 2023

The WIVERN (WInd VElocity Radar Nephoscope) concept, now in Phase 0 of the ESA Earth Explorer program, promises to complement Doppler wind lidar by globally observing, for the first time, the vertical profiles of winds in cloudy areas. The mission will also strengthen the cloud and precipitation observation capability of the Global Observing System by providing unprecedented revisit time of cloud and precipitation vertical profiles. The mission hinges upon a single instrument, i.e., a dual-polarization Doppler W-band scanning cloud radar with a 3 m circular aperture non-deployable main reflector. The WIVERN antenna conically scans a large swath (of about 800 km) around nadir at an off-nadir angle of about 38o at 12 rpm (revolutions per minute). This viewing geometry allows daily revisits poleward of 50°, 50-km horizontal resolution, and approximately 1-km vertical resolution. A key element is the use of closely spaced pulse pairs one of which is H polarised the other V polarised, so that the target does not have time to reshuffle, and, providing there is no significant cross-talk between the two returns, the high velocities associated with wind storms can be retrieved. In this paper we will discuss the scientific objectives of the mission and will outline some of the technical challenges of the measuring technique. In particular we will discuss how to correct for wind biases introduced by the satellite motion and wind shear across the beam, how to account for cross-talk between the H and V returns due to depolarisation by meteorological targets, how to calibrate the instrument and how to identify mis-pointing of the antenna that could affect Doppler accuracy. We will also present examples of Level 1 products via an end to end simulations applied to high resolution cloud resolving models and expected performances of the instrument in terms of cloud/precipitation and wind coverage.
Network geometries influence responses of alluvial river systems to external forcing
Authors: McNab Fergus , Schildgen Taylor , Turowski Jens , Wickert Andrew
Published: February 2023

Alluvial rivers transport sediment from erosional source regions to sedimentary basins downstream. Erosion and precipitation rates control their sediment and water supplies, tectonic processes drive uplift or subsidence along their lengths, while sea or lake levels set their base levels. Changes in these external conditions cause them to adjust their slopes and sediment transport rates. Geomorphic and stratigraphic archives that develop alongside and downstream of alluvial rivers may therefore record information about past climatic and/or tectonic change and their influence on landscapes. Much recent work has aimed to understand precisely how alluvial rivers respond to changes in external forcing, using a range of numerical and laboratory modelling approaches. Many of these conceptual studies have used a simplified, one-dimensional spatial domain in which sediment and water discharge are either held constant or increase continuously downstream (e.g., according to Hack's law). Such studies have emphasised, among other important findings, that the timescales over which a system responds to external forcing is strongly influenced by its length. However, in real rivers, water and sediment accumulate at discrete intervals as tributary streams coalesce. This discrepancy complicates the application to real catchments of concepts developed in one-dimensional modelling studies, since, for example, the 'length' of a river network is not clearly defined. Here, we explore how incorporating realistic network geometries influences the behaviour of an alluvial river model. We use a model describing the long-profile evolution of transport-limited gravel-bed rivers which takes a non-linear diffusive form. We construct networks by linking individual segments, so that their sediment and water supplies are set by segments immediately upstream and their base levels are set by segments immediately downstream. We show that significant complexity can arise locally, so that studies aiming to understand specific segments within a catchment should take into account the geometry of that catchment. However, properties that integrate over the entire catchment, such as its total sediment export, are adequately predicted by a simplified one-dimensional model—provided an appropriate lengthscale is chosen. We conclude that, while care is required in some circumstances, one-dimensional models can provide useful insights into the general behaviour of alluvial river networks.
The functional roles of mucus during aggregation
Authors: Guhra Tom , Wonneberger Arnold , Stolze Katharina , Ritschel Thomas , Totsche Kai Uwe
Published: February 2023

Soil organisms influence pedogenesis on a molecular level through the production of biopolymers which potentially interact with soil minerals depending on their molecular properties. Specifically, biopolymers can inhibit aggregation as separation agent or promote aggregation as bridging agent (Guhra et al. 2022). Mucus, a biopolymer excreted by earthworms consisting mainly of proteins, polysaccharides, and, to a lesser extent, lipids, has often been neglected so far, despite earthworm's fundamental contribution to soil quality and structuring via bioturbation. In our study, we investigate the role of cutaneous earthworm mucus (CEM) of L. terrestris during the formation of organo-mineral associations and aggregates. For this purpose, batch experiments were carried out with goethite and CEM at different pH values and increasing CEM concentrations resulting in the formation of mucus-goethite associations. Afterwards, the (homo/hetero) aggregation of these newly formed mucus-goethite associations with quartz particles was investigated in response to mucus-C loadings on mineral surfaces and CEM concentration in solution.Our experiments showed a pH dependent CEM structure and an adsorption to goethite controlled by concentration and pH. Polysaccharides from CEM adsorb preferentially under acidic conditions (pH 3) and low CEM concentration (6 mg mucus-C/l). In contrast, a stronger adsorption of proteins was observed at higher CEM concentrations (30 mg mucus-C /l). In subsequent aggregation experiments, the hetero-aggregation rate of organo-mineral associations and quartz was decreased at low C-loadings and increased at high loadings in comparison to the CEM-free reference. Furthermore, the aggregation between goethite particles was inhibited by electrostatic/steric repulsion (separation agent) when high CEM concentrations were present in solution (mineral:mucus ratio of 17), while CEM functions as bridging agent at low relative CEM supply (mineral:mucus ratio of > 83).The formation and the aggregation behavior of mucus-mineral associations contribute to nutrient/carbon storage as well as structure formation in soil. The composition, function, and (im-)mobilization of CEM and corresponding organo-mineral associations in earthworm-influenced soil structures is shaped by CEM availability and the structure/reactivity of CEM affected by environmental parameters.  References:Guhra, T., Stolze, K. and Totsche, K.U. 2022. Pathways of biogenically excreted organic matter into soil aggregates. Soil Biology and Biochemistry, 164, 108483.
Inverse modelling for trace gas surface flux estimation, impact of a non-diagonal B-matrix
Authors: Bannister Ross
Published: February 2023

One of the most appealing uses of data assimilation is to infer useful information about a dynamical system that is not observed directly. This is the case for the estimation of surface fluxes of trace gases (like methane). Such fluxes are not easy to measure directly on a global scale, but it is possible to measure the trace gas itself as it is transported around the globe. This is the purpose of INVICAT (the inverse modelling system of the chemical transport model TOMCAT), which has been developed here. INVICAT interprets observations of (e.g.) methane over a time window to estimate the initial conditions (ICs) and surface fluxes (SFs) of the TOMCAT model.This talk will show how INVICAT has been expanded from a diagonal background error covariance matrix (B-matrix, DB) to allow an efficient representation of a non-diagonal B-matrix (NDB). The results of this process are mixed. A NDB-matrix for the SF field improves the analysis against independent data, but a NDB-matrix for the IC field appears to degrade the analysis. This paper presents these results and suggests that a possible reason for the degraded analyses is the presence of a possible bias in the system.