bluuebunny/crossref_metadata_2025 huggingface dataset:
Study of environmental pressure of industrial effluent on rivers with a composed pressure index
Authors: Di Fluri Paola , Di Talia Valentina , Leonardi Antonio , Antonioni Giacomo , Domeneghetti Alessio , Cozzani Valerio
Published: March 2022

The deterioration of superficial water quality is a relevant issue as regards water management. Until today, most European rivers do not achieve qualitative standards defined by the Water Framework Directive (WFD). Given the goals of the WFD and taking into account current guidance for water quality management, this study has been carried out to evaluate pressures of anthropic activities - like industrial effluents, wastewater treatment plants, waste-to-energy plant, waste handling facilities, contaminates sites- on superficial waters.

In this study, we propose a simplified multidisciplinary methodology to perform a semi-quantitative analysis of water pressures on river segment starting from easily accessible data, thus attempting to overcome the endemic scarcity of monitoring data. In particular, the methodology proposes a procedure for: (1) identifying river segment exposed to pollution spills by the application of an expeditive raster-based numerical model; (2) determining a pressure index value for each identified river segment in relation to allocated spills. The developed pressure index offers the possibility of quantifying the significant pressures of several pollutant hotspots that impact simultaneously on a single river segment. The methodology has been tested over two rivers differently exposed to industrial and anthropogenic pressure and for which punctual environmental pollution hotspot were available at catchment scale.

The results allow to identify river segments most exposed to pollutant spills and, based on pressure index values, to do a comparative analysis between rivers segments with similar characteristics or to draw up a ranking magnitude of the river pressures. In this prospective, the developed methodology can represent a solid tool for decision-making processes and predictive studies in areas with no, or poor, monitoring data.
Precession-scale variability of upwelling in the Arabian Sea and its implications for proxies of Indian summer monsoon
Authors: Jalihal Chetankumar , Srinivasan Jayaraman , Chakraborty Arindam
Published: March 2022

Upwelling along the western boundary of the Arabian Sea and the Indian summer monsoon rainfall are positively correlated in modern observations. Upwelling transports nutrients into the euphotic zone and thus controls primary productivity. Therefore, primary productivity in the region of upwelling has been used to reconstruct monsoons of the distant past. Such reconstructions suggest that monsoons lag insolation by about 9 kyrs (nearly out-of-phase), contrary to several speleothem-based reconstructions that indicate a more in-phase relation of monsoon with insolation. Using results from transient as well as time-slice experiments, we have shown that factors other than the Indian monsoon affect upwelling on the precession time scales. These factors modulate the spatial extent of upwelling, resulting in the precession-scale variability in primary production. This is in contrast with modern observations, where most of the variations in primary productivity are a result of changes in the intensity of upwelling. We find that the spatial extent of upwelling is nearly out-of-phase with insolation. Thus, primary productivity lags insolation. We conclude that primary productivity in the Arabian Sea is not a good proxy for the Indian summer monsoon rainfall.
Effects of burrowing animals on soil erosion for Chile derived with a fully parameterized erosion model based on in-situ measurements, remote sensing and machine learning
Authors: Grigusova Paulina , Larsen Annegret , Brandl Roland , Chifflard Peter , Farwig Nina , Kraus Diana , Übernickel Kirstin , Bendix Jörg
Published: March 2022

To date, hillslope-wide effects of burrowing animals on soil erosion, infiltration, surface runoff, water storage and field capacity are hardly understood. Consequently, the effects of burrowing animals are not yet included in erosion models. A suitable approach considering their impacts in erosion models is lacking but needed in order to fully understand the feedbacks between biosphere and sediment fluxes.

For this presentation, we combined in-situ measurements, high resolution remote sensing data and machine-learning methods with a Daily based Morgan-Morgan-Finney soil erosion model for hillslopes along a climate gradient from arid to humid Chile. To parameterize the erosion model, we trained random forest models to upscale in-situ measured soil properties and the presence of animal burrows to each catchment using high-resolution WorldView-2 data. We conducted a land cover classification to provide the vegetation cover. ith this data, we parametrised one model per climate zone. The model was validated using in-situ installed sediment traps. Model experiments in- and excluding animal burrows were conducted to determine the daily and yearly impacts of burrowing animals on soil erosion, infiltration, surface runoff, subsurface runoff, water storage and field capacity on the burrow and hillslope scale at 0.5 m grid resolution.

The presence of burrows increased sediment erosion, infiltration and water storage and decreased surface runoff and field capacity. The effects were most pronounced on the daily and burrow scale in the semi-arid and mediterranean climate zone. In the semi-arid climate zone, the burrows heavily increased surface infiltration and subsurface runoff. In the mediterranean climate zone, the distribution of burrows had an impact on the surface runoff and increased the erosion rate in the adjusting areas without burrows. In the arid zone, the impact of burrowing animals was solely detectable during sporadically occurring heavy rains.

Our study presents, to our knowledge, for the first time a soil erosion model which includes burrowing animal activity. The results clearly underpin the general importance to consider burrowing animals in erosion modelling.
Tectonics of the Western Jura Fold-and-Thrust Belt: from the Geneva Basin to the Bienne Valley (France). Mapping and forward modelling.
Authors: Marro Adeline , Sommaruga Anna , Hauvette Louis , Borderie Sandra , Schori Marc , Mosar Jon
Published: March 2022

The arcuate Jura Mountains Fold-and-Thrust Belt (FTB) is situated in the NW Alpine Foreland and its formation is related to the Alpine orogeny. The western part of the Jura FTB, investigated here, is situated in France to the north of the Geneva Basin (Switzerland). The geothermal project “GEothermie2020”  of the larger Geneva area allowed us to re-assessed the structural geology and the kinematic evolution of the internal part of Western Jura FTB from the Geneva Basin (Switzerland) to the Bienne Valley (France).

Stratigraphic harmonization, new geological and tectonic maps, new seismic interpretation, and a new near top Basement surface were used to construct a kinematic model. This model using forward modelling techniques has been developed in the software Movetm by Petroleum Experts. The forward model relies on fault-bend fold, trishear, and fault-parallel flow algorithms, and provides a valid and balanced cross-section. The model is constrained by surface, well and seismic data. Therefore, the depth of the near base Mesozoic horizon has been well constrained by seismic depth-converted lines. Thus, we can show, that the top basement under the Jura domain is dipping 1.7° to the SE, whereas under the Geneva Basin it is dipping between 2.7°-3.3° to the SE. The results of our modelling show a shortening of 23.6 km for the western Internal Jura FTB along a basal detachment and a forward stepping deformation accompanied by minor back-stepping thrust sequences. The first deformation is attributed to the thrusting of the Crêt de la Neige anticline followed by the Crêt Chalam thrust and its imbrications. Then, the Tacon thrust and finally the Bienne thrust nucleate. Imbricate fault-bend folding explains the high southern slopes of the anticlines found in this area. In addition to the primary décollement level situated at the base of the Keuper Group evaporites, three other detachment levels are found in marly layers. Using such a multiple thrust horizon approach avoids having to introduce thick unaccounted for evaporitic duplexes in the Keuper units, basement horst, or inverted Permo-Carboniferous grabens. The change in dip of the top basement located under the SE flank of the Crêt de la Neige anticline, at the transition of the Jura FTB to the Molasse Basin, is considered to be linked to a preexisting Paleozoic normal fault and could correspond to the northern edge of a suspected Permo-Carboniferous graben interpreted on seismic lines under the Geneva Basin. This step can be considered as an initiation point for structures developing in the detached cover.
Sensitivity of hydrological predictions to ecosystem adaptation in response to climate change: the effect of time-dynamic model parameters
Authors: Bouaziz Laurène J.E. , Aalbers Emma E. , Weerts Albrecht H. , Hegnauer Mark , Buiteveld Hendrik , Lammersen Rita , Stam Jasper , Sprokkereef Eric , Savenije Hubert H.G. , Hrachowitz Markus
Published: March 2022

Typically, the future hydrological behavior of a river basin, for example as a result of climate change, is predicted using hydrological models calibrated with historical observations. In reality, hydrological systems, and hence model parameters, experience almost continuous change in time and space. More specifically, there is growing evidence that vegetation adapts to changing conditions by adjusting its root-zone storage capacity, i.e. the amount of water in the unsaturated subsurface which is available to the roots of vegetation for transpiration. Additionally, other species may become dominant under natural and anthropogenic influence. In this study, we test the sensitivity of hydrological model predictions to changes in vegetation parameters that reflect ecosystem adaptation to climate and potential land-use changes. In other words, if the climate changes, how should our models change and what is the effect on the hydrological response? Our methodology directly uses projected climate data to estimate how vegetation adapts its root-zone storage capacity at the catchment scale to changes in hydro-climatic variables and potential land-use change. We test the hypothesis that changes in the hydrological response under global warming are more pronounced when explicitly considering changes reflecting adaptation of the root-zone storage capacity of vegetation. We compare a stationary benchmark model with several non-stationary model scenarios reflecting climate and potential land-use changes in the Meuse basin. We found that the larger root-zone storage capacities (+34%) in response to warmer summers under projected +2K global warming result in up to -15% less streamflow in autumn due to up to +14% higher summer evaporation in the non-stationary scenarios compared to the stationary benchmark scenario. By integrating a time-dynamic representation of changing vegetation properties in hydrological models, we make a potential step towards more reliable hydrological predictions under change.
Reconstructing zonal precipitation from sparse historical observations using climate model information and statistical learning
Authors: Egli Marius , Sippel Sebastian , Pendergrass Angeline , de Vries Iris , Knutti Reto
Published: March 2022

Changes in precipitation due to climate change are having and will continue to have substantial societal impact. Although physical process understanding allows insights into some of the model-projected changes, we face many challenges when turning to observations in order to detect these changes, such as large internal variability and limited observational coverage both in time and space.

Here, we aim to address these challenges with a tool from statistical learning, by implementing a regularized linear model to (1) reconstruct historical seasonal full (land+ocean) zonal mean precipitation starting in 1950 and (2) detect anthropogenically forced changes in zonal mean precipitation. The linear model is trained using a climate model large-ensemble archive with its coverage reduced to match gridded station observations on land only. Once trained, the linear model can reconstruct the full zonal mean precipitation from the partial coverage given by observations. The reconstructions (1) are compared against independent satellite observations and other sources of historical precipitation reconstructions. Our approach is successful at recovering a large part of the variability in zonal precipitation. In the Northern hemisphere extra-tropics, with relatively high station coverage, the reconstructions achieve an agreement of R=0.8 (Pearson correlation) or higher with independent satellite precipitation. But correlation values decrease considerably in the Southern hemisphere and parts of the tropics. Next, we estimate trends in the forced response (2) in seasonal zonal-mean precipitation, many of which lie outside the likely range in a preindustrial climate. The detected trends are, in line with the projection of climate models forced with historical greenhouse gas and aerosol emissions but are sensitive to the underlying observational data set.

Our results show that for large scale metrics such as seasonal zonal mean precipitation our reconstruction method can facilitate new insights for the detection and attribution of changes in the hydrological cycle. 
Discrete fracture network analysis of Devonian carbonate rocks in Western Germany: Implications for deep geothermal energy, heat exploitation and anthropogenic fault reactivation
Authors: Verdecchia Alessandro , Pederson Chelsea , Smeraglia Luca , Lippert Kevin , Immenhauser Adrian , Harrington Rebecca
Published: March 2022

Faults and fractures in carbonate reservoirs strongly influence subsurface fluid movement and can determine the success or failure of geothermal energy and heat production projects. Characterizing their physical and hydraulic properties is therefore crucial. Firstly, because they strongly control the secondary porosity and permeability of the reservoir, which are key parameters for the estimation of the reservoir quality, and for the planning of injection/extraction strategies. Secondly, because upon anthropogenic reactivation, they can lead to felt seismic activity, which could interrupt operations and potentially lead to damage to infrastructure and endanger the population.

Devonian carbonate rocks underlie a vast portion of North Rhine-Westphalia in Western Germany. Their stratigraphic thickness (up to 1,300 m), location, and depth, make them a potential reservoir for deep geothermal heat and energy exploitation. While estimated at depths between 1.3 km and 6 km, outcrop analogues of these Devonian carbonates are exposed in a number of quarries in the region.

This work quantitatively characterizes the fracture and fault distribution and permeability of the Devonian limestones and dolostones exposed at the the Steltenberg quarry, located at the northern margin of the Remscheid-Altena Anticline. The units outcropping in the quarry are tectonically affected by splays of the WSW-ENE-trending Ennepe thrust (Variscan), and by post-Variscan NNW-SSE-trending normal faults. We combine field structural analyses and fracture characterization using scan lines with a 3D digital outcrop model and fracture analyses using UAV imagery, to produce 3D Discrete Fracture Network (DFN) models. Preliminary results show three main fracture sets: WSW-ENE-trending and S-dipping fractures parallel to the Ennepe Thrust, WSW-ENE-trending and N-dipping bedding-parallel fractures, and NNW-SSE-trending sub-vertical fractures parallel to the regional post-Variscan normal faults. Our DFN modeling suggests that the latter represent the main pathways for fluid flow with permeability values up to 10-14 m2.

As next steps we will use the DFN modeling results (e.g., fractures sets, permeability tensor) as input for a 3D thermo-hydro-mechanical finite element model aimed at predicting fluid flow, pressure, and stress changes in a potential geothermal reservoir. Modeling, together with fault-related parameters such as slip tendency and fracture susceptibility, will help estimate the potential for fault reactivation and induced seismicity in the region.
Trends in short-term precipitation variability
Authors: Beranova Romana , Huth Radan
Published: March 2022

Since long-term changes in precipitation variability are an important aspect of climate change, it is necessary to know whether and how they are changing. We consider two measures of short-term precipitation variability: (i) dry-to-wet and wet-to-wet transition probabilities; they are sufficient for the description of the other two probabilities (dry-to-dry and wet-to-dry) provided precipitation occurrence follows the two-state first-order Markovian process and (ii) mean duration of dry and wet spells, that is, sequences of days without and with measurable precipitation.

The daily precipitation data are taken from European Climate Assessment and Dataset project. We examine 395 precipitation station series from 1961 to 2010. Long-term trends of seasonal values of variability measures and their statistical significance are calculated by non-parametric methods (Mann-Kendall test, Kendall statistic). We found out that statistically significant trends of transition probabilities are more frequent in winter than in summer. In winter, there are positive trends of wet-to-wet probabilities and negative trends of dry-to-dry probabilities in northern Europe.
Towards better long-term integration of earth science data from landscape scale to detail studies 
Authors: Whalley W Brian
Published: March 2022

This paper outlines a recording schema for features, events, processes and data identified by decimal latitude-longitude locations. Such geolocation is preferable to using only names or geomorphic features because points, areas and lines can be uniquely identified, represented on a GIS (or Google Earth) and (ideally) searched for in any literature (geomorphic, hydrological, tectonic, ecological etc). It is thus useful for location and integrating ‘critical zone’ studies and to develop knowledge management systems. Such systems would include geolocated data points in tables, diagrams or as maps. Downslope transects, on hillslopes most notably, can be identified by geolocated points appended to a bearing. This bearing will generally be downslope to provide a pathline that can be associated with data points corresponding to e.g. downhill movement, fluxes, material properties, dated surfaces as well as locations that may correspond to geomorphic features. Transects may link not just surface features or ‘processes’ but represent a flowline in continuum mechanics. Data points can be referenced according to either/or/both Eulerian and Lagrangian schemes as appropriate. The schema also suggests sharing data and interoperability for measurement methods and data that will be especially useful for modelling purposes.
The Importance of Acid Processed Meteoric Smoke Relative to Meteoric Fragments for Crystal Nucleation in Polar Stratospheric Clouds
Authors: James Alexander , Pace Finn , Sikora Sebastien N. F. , Murray Benjamin J. , Mann Graham W. , Plane John M. C.
Published: March 2022

Nitric Acid Trihydrate (NAT) crystal formation in the absence of water ice is important for a subset of Polar Stratospheric Clouds (PSCs) and thereby Ozone. However, nucleation of these crystals is not understood.

It has been suggested previously that either fragmented meteoroids or meteoric smoke particles (MSPs), or possibly both, are important as heterogeneous nuclei. The role of H2SO4, which is present in liquid PSCs, in these nucleation processes has not been investigated. It is known that metal-containing Meteoric Smoke Particles (MSPs) are processed, partially dissolving whilst some components re-precipitate within H2SO4 droplets, producing silica and alumina particles which differ in size from the original MSPs. We recently found that analogues for nanoparticulate MSPs have a low ability to nucleate NAT relative to larger particles of similar material, suggesting that the size of particles may be a critical parameter for the nucleating ability of silica particles.  We previously showed experimentally that nano-particulate fumed silica is a poor promoter of nucleation, whilst micron scale fused quartz was found to be effective. Both materials have similar chemical and structural (crystallographically amorphous) properties.

In this study we developed a model using Classical Nucleation Theory (CNT) where we account for surface curvature of primary grains. This model is able to account for the discrepancy in nucleation effectiveness of fumed silica and fused quartz, by treating them as having the same nucleating ability (contact angle) but differing particle size (or equivalently surface curvature), assuming interfacial energies which are physically reasonable given literature measurements. We also performed new experiments which allowed us to refine our understanding of the H2SO4 sensitivity of NAT nucleation by meteoric fragments. Combining sedimentation modelling with our results and recent experiments on fragmentation of incoming meteoroids suggests that fragments are unlikely to be important as heterogeneous nuclei. However, the CNT model developed here provides evidence that nucleation of NAT on (10s nm) MSP analogues is effective enough to explain observed NAT crystal number concentrations in PSCs (without ice).
Landscape analysis of runoff and sedimentation based on land use/cover change in two typical watersheds on the Loess Plateau
Authors: Liu xiaojun
Published: March 2022

Land use change is a major influencing factor in ecological and environmental issues, and sedimentation and runoff variations caused by land use change have emerged as important research areas. The aims of this study were to determine changes in landscape patterns, and runoff and sedimentation characteristics, and to investigate the relationship between landscape metrics (LMs), runoff, and sedimentation in two watersheds. Four key results were obtained. (1) Grassland (GRA) was the dominant landscape in the two watersheds. Unused land (UNL) in the Tuweihe watershed and farmland (FAR) in the Gushanchuan watershed experienced the greatest transformations, with changes in area of 453.94 and 52.85 km2, respectively, between 1985 and 2010. (2) The landscape in the watersheds tended to become regular, connected, and aggregated. The landscape stability of the Tuweihe watershed was higher than that of the Gushanchuan watershed. (3) Annual runoff and sediment levels gradually decreased. The runoff in the Tuweihe watershed was greater than in the Gushanchuan watershed, but the sediment yields of the two watersheds were similar. There was a significant relationship between annual runoff and sedimentation (P <0.01). (4) The LMs had a significant linear relationship with runoff and sedimentation (P <0.01). The correlation coefficients for LMs and runoff were higher than those for LMs and annual sedimentation yield. Shannon’s evenness index (SHEI) and the patch cohesion index (COHESION) had the greatest effects on runoff and sedimentation. Our results suggested that the relationship between the LMs, and runoff and sedimentation could provide a scientific basis for the prevention and treatment of water loss and soil erosion.
Keywords： land use/cover change; landscape; runoff; sedimentation; Yellow River
Mapping Sweden’s drainage ditches using deep learning and airborne laser scanning
Authors: Lidberg William , Paul Siddhartho , Westphal Florian , Ågren Anneli
Published: March 2022

Drainage ditches are common forestry practice across northern European boreal forests and in some parts of North America. Ditching helps with lowering the groundwater level in the wet parts of the forest to improve soil aeration and to support tree growth. However, the intensive ditching practice pose multidimensional environmental risks, particularly for degradation of wetland and soil, greenhouse gas, increased nutrient and sediment loadings to water bodies, as well as biodiversity loss. At the same time there is a discrepancy between the potential significance of artificial water bodies, such as drainage ditches and their low representation in scientific research and water management policy. A comparison with a national inventory of Sweden showed that only 9 % of drainage ditches are present on the best avalible map of Sweden. The increasing understanding of the environmental risks associated with forest ditches together with the poor representation of ditch networks in existing maps of many forest landscapes makes detailed mapping of these ditches a priority for sustainable land and water management. Here, we combine two state-of-the-art technologies – airborne laser scanning and deep learning - for detecting drainage ditches on a national scale.

 

A deep neural network was trained on airborne laser scanning data and 1607 km of manually digitized ditch channels from 10 regions spread across Sweden. 20 % of the data was set aside for testing the model.  The model correctly mapped 82 % of all small drainage channels in the test data with a Matthew's correlation coefficient of 0.72. This approach only requires one topographical index, a high pass median filter calculated from a digital elevation model with a 1 m spatial resolution. This made it possible to scale up over large areas with limited computational resources and the trained model was implemented using Microsoft Azure to map ditch channels across all of Sweden. The total mapped channel length was 970 00 km (equivalent to 24 times around the world). Visual inspection indicated that this method also classifies natural stream channels as drainage channels, which suggests that a deep neural network can be trained to detect natural stream channels in addition to drainage ditches. The model only required one topographical index which makes it possible to implement this approach in other areas with access to high resolution digital elevation data.
Modeling seawater flooding, ponding, and infiltration processes under future tsunami scenarios: A case study at Niijima Island, Japan
Authors: Liu Jiaqi , Brunner Philip , Tokunaga Tomochika
Published: March 2022

Tsunami disasters can cause infiltration of seawater into coastal unconfined aquifers over large scales, which would induce long-term salinization of groundwater resources. According to the report by Cabinet Office of Japan (2011), an earthquake of 9.0 Mw will very possibly occur along the Nankai Trough during the years 2011-2030. Under the worst tsunami scenario, the coastal area of Niijima Island, Japan, will be inundated by seawater up to about 15 m a.m.s.l. (above mean sea-level) (Tokyo Disaster Management Council, 2013). As a result, groundwater, the only freshwater source for the island, will face severe salinization. In order to assess the risk of groundwater salinization under such scenario, a 3-D numerical model of Niijima Island was developed using the HydroGeoSphere code which can solve coupled surface-subsurface flow processes.  The results showed that the simulated early stage seawater ponding at the land surface was controlled by the type (DEM or DSM) and spatial resolution of topographic data  used in the model. This suggested that high-resolution topographic data considering the existence of artificial structures should be preferred for modeling seawater ponding and infiltration after tsunamis in urbanized areas. Furthermore, compared with the baseline case, the reduction in hydraulic conductivity and the Manning’s roughness coefficient in places of buildings and roads reduced the amount of seawater infiltration. The results highlighted the land surface conditions as an important indicator for the vulnerability of groundwater resources to tsunami-induced seawater infiltration.
Towards a monitoring approach for understanding permafrost degradation and linked subsidence in Arctic peatlands
Authors: Sjogersten Sofie , de la Barreda Bautista Betsabe , Boyd Doreen , Ledger Martha , Siewert Matthias , Chandler Chris , Bradley Andrew , Gee David , Large David , Olofsson Johan , Sowter Andrew
Published: March 2022

Permafrost thaw resulting from climate warming is threatening to release carbon from high latitude peatlands. The aim of this research was to determine subsidence rates linked to permafrost thaw in sub-Arctic peatlands in Sweden using historical orthophotographic (orthophotos), Unoccupied Aerial Vehicle (UAV) and Interferometric Synthetic Aperture Radar (InSAR) data. The orthophotos showed that the permafrost palsa on the study sites have been contracting in their areal extent, with the greatest rates of loss between 2002-2008. The surface motion estimated from differential digital elevation models from the UAV data showed high levels of subsidence (maximum of -25 cm between 2017-2020) around the edges of the raised palsa plateaus. The InSAR data analysis showed that raised palsa areas had the greatest subsidence rates with maximum subsidence rates of 1.5 cm between 2017-2020, however, all wetland vegetation types showed subsidence. We suggest that the difference in spatial units associated with each sensor explains parts of the variation in subsidence levels recorded. We conclude that InSAR was able to identify areas most at risk of subsidence and that it can be used to investigate subsidence over large spatial extents, whereas UAV data can be used to better understand dynamics of permafrost degradation at a local-level. These findings underpin a monitoring approach for these peatlands.
Arbuscular mycorrhizal hyphosphere as a soil nutrient turnover hotspot
Authors: Jansa Jan , Bukovská Petra , Rozmoš Martin
Published: March 2022

Arbuscular mycorrhizal fungi (AMF) efficiently take up mineral nutrients such as phosphorus and nitrogen (N) from the soil solution, and trade them for organic carbon with their host plants. Acquisition of nutrients bound in organic forms by the AMF under unsterile soil conditions has previously been reported, assuming an important role of soil prokaryotes, yet mostly without proper mechanistic understanding. Here we present a synthetic approach to study involvement of such inter-kingdom interactions in utilization of organic nitrogen by a mycorrhizal plant. We employ 15N-labelled chitin (as an organic N source) added to AM fungal (Rhizophagus irregularis) hyphosphere under in vitro conditions, with or without other microorganisms. Upon presence of Paenibacillus sp., the AMF and their associated host plant obtained several-fold larger quantities of N from the chitin than they did with other bacteria, whether chitinolytic or not. Moreover, upon adding a protist Polysphondylium pallidum to the hyphosphere with Paenibacillus sp., the gain of N from the chitin by the AMF and their associated plant further and significantly increased by another 60+%, pointing to soil microbial loop as the underlying mechanism.

 

This work will appear shortly in the ISME Journal.

Reference: Rozmoš M, Bukovská P, Hršelová H, Kotianová M, Dudáš M, Gančarčíková K, Jansa J (2022) Organic nitrogen utilization by an arbuscular mycorrhizal fungus is mediated by specific soil bacteria and a protist. ISME Journal, in press. doi 10.1038/s41396-021-01112-8 .
The optimal processing chain for flood mapping using polarimetric SAR in a temperate zone wetland
Authors: Gierszewska Monika , Berezowski Tomasz
Published: March 2022

In this study, we investigated the influence of speckle filters and decomposition methods with different combinations of filter and decomposition windows sizes on classification accuracy. The study area was a part of Biebrza National Park, located in Northeast Poland. The C-Band SAR image from Radarsat 2 sensor was processed using various speckle filters (boxcar, IDAN, improved Lee sigma, refined Lee) in 5x5, 7x7, 9x9, and 11x11 pixel window sizes. We processed the filtered data using nine polarimetric decompositions also in 5x5, 7x7, 9x9, and 11x11 pixel window sizes. We used the calculated polarimetric features to conduct a supervised classification with random forest machine learning algorithms for each combination of processing parameters in three different scenarios: (1) each decomposition product was used separately as a model input; (2) all decomposition products with the same speckle filtering method were used as a model input; (3) all decomposition products with all speckle filtering methods were used together as the model input. Overall, the most accurate classification model (87%) was produced in scenario 3 with an 11x11 filter and decomposition windows. In scenario 1, the highest overall accuracy achieved the Cloude-Pottier decomposition (72%) and the lowest produced the Touzi decomposition (38%). In scenario 2, the IDAN filter provided the highest accuracy (84%) with an 11x11 filter window and a 9x9 decomposition window. The obtained results show that the selection of appropriate processing parameters is an important step in the SAR data classification workflow. Our study also indicates the most suitable combination of radar image processing parameters for wetland classification.
The effect of space weather, proxy parameters of solar activity, and stratospheric phenomena on the concentration of cosmogenic radionuclide 7Be (in the Czech Republic)
Authors: Podolská Kateřina , Kozubek Michal , Hýža Miroslav , Šindelářová Tereza
Published: March 2022

Cosmogenic radionuclides concentrations are predominantly determined by the solar activity and space weather around the Earth, forming an important source of cosmic-origin background radiation in the terrestrial environment. The highest values of such radiation are observed during the solar minima because the penetrability of the Earth’s magnetosphere is greatest at that time. Beryllium 7Be binds to aerosols and is transported within a few years to the Earth’s surface. Its concentrations are higher during the spring and summer months when the stratospheric 7Be penetrates the troposphere as a result of the exchange of air masses between the troposphere and stratosphere. We compare periods of strong solar and geomagnetic storms with periods of very low solar activity in the longitudinal view during the years 1986 – 2020.

For a better understanding of the process dynamics, in our work we investigate the coupling of concentrations of the cosmogenic radionuclide 7Be (time series of activity concentration of 7Be in aerosols) to space weather parameters around the Earth (Kp planetary index, disturbance storm time Dst, proton density, proton flux), proxy parameters of the solar activity (intensity of solar radio flux, relative sunspot number), stratospheric dynamics parameters (temperature, zonal component of wind, O3), and aggregates of strong atmospheric frontal transition. The beryllium radionuclide 7Be concentration was evaluated by the corresponding activity in aerosols on a weekly basis at the National Radiation Protection Institute Monitoring Section in Prague.

We also perform the case study of cosmogenic radionuclide 7Be concentrations during the period of strong solar and geomagnetic storm in November 2021 with the ERA5 reanalysis data, and Aeolus satellite lidar wind measurements.
A small DOAS device for student training
Authors: Kausch Wolfgang , Kimeswenger Stefan , Przybilla Norbert , Noll Stefan
Published: March 2022

Differential optical absorption spectroscopy (DOAS) has become a standard method for analysing the amount of various molecular species in the Earth's atmosphere. For student education we have developed a small device aiming to be used for practising this technique. It is based on three 50mm aperture sized telescopes, which are aligned on a SkywatcherAZ-EQ5 astronomical mount enabling a multi-axis movement. Each of the three telescopes feeds an individual spectrograph to cover the entire wavelength range between 300 and 980nm in three arms: Ultraviolett/blue (UVB) arm, ranging from 300-507nm (Stellarnet BLUE-Wave UV2-14 spectrometer, 0.2nm resolution, 14µm slit); Visual (VIS) arm covering 500-680nm (Stellarnet BLUE-Wave NIR4-14, 0.2nm resolution, 14µm slit); red/near-infrared (NIR) arm: 600-980nm (Stellarnet  BLUE-Wave NIR2-14, 0.4nm resolution, 14µm slit). All three spectrometers are equipped with a detector amplification lens upgrade. The main lens of the telescope feeding the UVB arm was replaced by one with a fused silica glass for a better UV transparency. In addition, we use wavelength-optimised 600µm fibres in each spectral arm.

The software to take the spectra is SpectraWiz v5.33. The data calibration is done with MIDAS, a software specifically developed for astronomical purposes. The final DOAS measurements are done with molecfit, a software originally developed to remove absorption features from astronomical spectra by fitting model-based synthetic transmission spectrum to absorption features in scientific data.

In this presentation we show a technical overview of this instrument, the concept of the experiment and some results. 
School-based disaster preparedness: a route to societal resilience? The case study of Ljungby municipality, Sweden
Authors: Covaciu Andra
Published: March 2022

Children spend around five days a week in school for almost the entire year. Thus, it is sensible to best prepare them for coping with the potential occurrence of hazardous events while they are in school. The present research aims to explore the perceived importance and feasibility of implementing school-based disaster preparedness (SBDP) by the means of a case study of Ljungby municipality, Kronoberg county, Sweden. Through the means of semi-structured interviews, questionnaires and secondary data, the research unravelled how the respondents, in the form of both students and school staff perceive SBDP, and whether they see it as a potentially useful tool for their schools. In addition, the paper focused on understanding how this type of disaster preparedness can contribute to the municipality’s resilience. We concluded that the respondents understand the importance of SBDP and consider that the administrations at school and municipality level should focus more on ensuring that crisis plans are available, as well as on short- and long-term strategic preparedness. In addition, a shift in focus from training only staff to including students as valuable resources and considering their levels of preparedness was noticed by the interviewees, as well as the need to increase the awareness regarding the available SBDP items in each school. The existent crisis plans might need additional consideration in order to ensure their adaptability to schools’ needs, capacities, lessons learnt and locations. Further studies are needed in regard to whether students-aimed SBDP can be used for creating a sustainable SBDP culture within communities, municipalities and later on, entire countries.
Modeling the propagation and run-out from gravel-silty clay landslide to debris flow in Shaziba, southwest Hubei Province, China
Authors: Hu Xudong , Ding Miao
Published: March 2022

Numerical modelling is the physically-based method for in-depth analyzing the process from landslide to debris flow. Particle flow analysis method (PFC) has the advantage of dealing with such processes, like debris flow formation, propagation, and deposition. Hence, our study to analyze the dynamic characteristics of a landslide-generated debris-flow, taking the Shaziba landslide-debris-flow as example, which occurred in Enshi City on June 8, 2020, under complex landslide material composition, Combined the field survey, unmanned aerial vehicle (UAV) aerial photography, and laboratory direct shear tests, the velocity, displacement and the characteristics of the landslide-generated debris-flow were simulated. The results indicated that the initial stage of the landslide starts with an overall motion acceleration with a time around 733 s. The maximum velocity of the landslide body is 17.5 m/s, and the maximum displacement is 1500 m with a total volume of 9.31×105 m3. The simulation results are closer to the actual landslide volume (1.0×106 m3) and the form of the dam in Qingjiang. The study reveals the mechanism of dam formation, which could be served as useful information for natural hazards management to prevent the river from being blocked by landslides or debris flows.
Total Exchange Flow in the Guadalquivir River Estuary
Authors: Diez-Minguito Manuel , Burchard Hans
Published: March 2022

The Total Exchange Flow (TEF) analysis framework computes the exchange flow in estuaries using isohaline coordinates. The TEF represents a paradigm for exchange flow estimates that is consistent with (steady-state) Knudsen-bulk values, and naturally allows quantifying mixing, which in turn controls the inflow and outflow fluxes of water and salinity.

This study provides preliminary estimates of TEF along the Guadalquivir River Estuary (Spain) at seven notable cross-sections during low river flows. The analysis combines observations recorded between 2008 and 2011 by a real time monitoring network and analytical model output for a well-mixed M2+M4 tidal flow with oscillating salinity. Exchange profiles and volume and salinity transports sorted by salinity classes are computed.

The results indicate that bulk along-channel TEF estimates decrease upstream. Incoming and outgoing water volume transports are about 10% larger than previous estimates based on gravitational circulation only. The largest net incoming water volume transport, viz. approx. 300 m3s-1, is attained at the lower part of the estuary, near where the largest salinity gradient is observed. This value is about 12-fold the normal river flow from the head dam at Alcalá del Río. Its corresponding representative TEF bulk salinity value is 20 psu, whereas the representative value for outflows at the same location is about 16 psu. In the middle part of the estuary, incoming TEF bulk volume values below 150 m3s-1 are obtained. As expected, negligible values are obtained in the upper part of the estuary near the head dam. Mixing completeness is larger than 75% at all cross-sections, thereby evidencing the poorly-stratified character of the Guadalquivir estuary.

Regarding the effects of tidal asymmetry, the inclusion of the M4 tidal constituent in the analysis does not improve significantly the TEF estimates (less than 1% at all cross-sections), although it might be the case in other estuaries or coastal seas. This ensues that the covariance between salinity and current seems to play a more important role in exchange flow in the Guadalquivir estuary. 
The Seasonal Evolution of the Supraglacial Hydrologic Network at Humboldt Glacier, Northwest Greenland.
Authors: Rawlins Lauren , Rippin David , Sole Andrew , Livingstone Stephen , Yang Kang
Published: March 2022

Supraglacial channels and lakes across the Greenland Ice Sheet form a key component in the routing and storage of surface meltwater during the summer melt season, yet to-date, their temporal evolution remains poorly mapped and quantified across the Greenland Ice Sheet. We produce the first high-resolution record of the seasonal supraglacial drainage network (channels and lakes) at Humboldt Glacier, northwest Greenland, spanning the melt seasons of 2016 to 2020. Using an automatic detection algorithm applied to Sentinel-2 imagery, which utilises a satellite-derived normalised difference water index (NDWI) and morphological operators, supraglacial channels and lakes were effectively mapped and quantified across the study region, including meltwater area, meltwater area fraction, channel drainage density (Dd), lake density and comparisons of satellite-derived drainage mapping to regional climate model (MAR) runoff.  

Results reveal the migratory behaviour of the supraglacial drainage network at Humboldt Glacier as surface runoff increases and the snowline recedes through the melt season. In the high melt years of 2016, 2019 and 2020, Dd commonly peaks in early-July as the ‘inefficient’ system (with hydrologically-connected saturated slush zones) advances inland, before decreasing as the system reaches maximum ‘efficiency’ and inland extent (late-July) before waning as the melt season ends. During these years, this annually-expansive network consistently reaches elevations of ~1450 m (~80km inland), with surface meltwater area covering between 7.2 - 11.6% of the area <1500 m. Retardation to this behaviour is notably observed within the low melt years of 2017 and 2018, when Dd and melt area do not peak until August.

Supraglacial lakes are also widely present within the drainage system, with their number and size also shown to peak with Dd before decreasing as the melt season progresses, attributed to increased moulin connectivity and subsequent lake drainage events. The combined meltwater area fraction (%) of both supraglacial channels and lakes is strongly correlated with MAR modelled surface runoff.

This work provides important advancements in the mapping, quantification and understanding of the expansive yet ephemeral supraglacial hydrologic system that exists across northwest Greenland Ice Sheet and its influence on the routing and evacuation of meltwater from these systems and beyond.
High stress deformation and short-term thermal pulse preserved in exhumed lower crustal seismogenic faults (Lofoten, Norway)
Authors: Menegon Luca , Campbell Lucy
Published: March 2022

Seismic rupture in strong, anhydrous lithologies of the lower continental crust requires high failure stress, in the absence of high pore fluid pressure. Several mechanisms proposed to generate high stresses at depth imply transient loading driven by a spectrum of stress changes, ranging from highly localised stress amplifications to crustal-scale stress transfers. High transient stresses up to GPa magnitude are proposed by field and modelling studies, but the evidence for transient pre-seismic stress loading is often difficult to extract from the geological record due to overprinting by coseismic damage and slip. However, the local preservation of deformation microstructures indicative of crystal-plastic and brittle deformation associated with the seismic cycle in the lower crust offers the opportunity to constrain the progression of deformation before, during and after rupture, including stress and temperature evolution.

Here, detailed study of pyroxene microstructures characterises the short-term evolution of high stress deformation and temperature changes experienced prior to, and during, lower crustal earthquake rupture. Pyroxenes are sampled from pseudotachylyte-bearing faults and damage zones of lower crustal earthquakes recorded in the exhumed granulite facies terrane of Lofoten, northern Norway. The progressive sequence of microstructures indicates localised high-stress (at the GPa level) preseismic loading accommodated by low temperature plasticity, followed by coseismic pulverisation-style fragmentation and subsequent grain growth triggered by the short-term heat pulse associated with frictional sliding. Thus, up to GPa-level transient high stress leading to earthquake nucleation in the dry lower crust can occur in nature, and can be preserved in the fault rock microstructure.