bluuebunny/crossref_metadata_2025 huggingface dataset:
Structure and evolution of the Dead Sea Transform
Authors: Fedorik Jakub , Afifi Abdulkader M.
Published: February 2023

The Dead Sea Transform (DST) extends from the Red Sea to the East Anatolian Fault, displaying various structural styles along its ~1100 km length. In this study, we combine previous work with new mapping of fault patterns and displacements, geochronological data, and analogue and numerical modeling to provide new insights on the temporal evolution of the DST.
In the southern DST, we mapped a 30 km wide distributed shear belt along the eastern margin of the Gulf of Aqaba (GOA), consisting of a distributed shear faulting, similarly to the western belt in Sinai. Total left lateral offset across the eastern distributed shear belt is ~ 15 km, with offset across individual faults ranging from a few meters up to 5.7 kilometers. Ar-Ar dating of sheared basalt dikes and U-Pb dating of calcite cements in faults indicate that the distributed shear system was activate between 22-16 Ma, overlapping with the rifting of the proto Red Sea and Gulf of Suez. This distributed shear is observed along the GOA and the deformed area narrowed along the Arava Valley. Distributed shearing marks the initial stage of continental break-up along the DST, which was abandoned by faulting concentration within the GOA and propagation of the DST towards the north.
The structural analysis of bathymetry data from the GOA and fault mapping along the entire DST highlight various structural styles: rotational transtension within the GOA, narrowing to simple strike-slip faulting of the Wadi Araba and Jordan Valley, and pull-apart basins along the Dead Sea, Sea of Galilee and Hula Basin. These structures are linked at depth to the principal displacement zone, nowadays-active plate boundary. Our analogue model produces similar structural styles and with the seismicity data it confirms that deformed area narrowed in the more recent stage of deformation. We also present an approach based on the boundary element method at the regional scale to test the structural interpretation of a complex transpressional mountain range of Lebanon Restraining Bend. These results are validated by structural evidences and highlight that various structural styles lead to formation of Mt. Lebanon, Anti-Lebanon and Palmyrides structures.
This review study of the DST emphasizes the role of structural styles, inherited structures and relative movement between tectonic plates in the transform continental break-up evolution.
Climate change impacts on crop production and soil carbon stock in a continuous wheat cropping system in southeast England
Authors: Liang Shuo , Sun Nan , Meersmans Jeroen , Longdoz Bernard , Colinet Gilles , Xu Minggang , Wu Lianhai
Published: February 2023

Understanding dynamics of soil organic carbon (SOC) stock in agroecosystems under climate change is imperative for maintaining soil productivity and offsetting greenhouse gas emissions. Simulations with the SPACSYS model were conducted to assess the effects of future climate scenarios (Representative Concentration Pathway (RCP) 2.6, 4.5 and 8.5) and fertilization practices on crop yield and SOC stock by 2100 for a continuous winter wheat cropping system in southeast England. Weather data between 1921 and 2000 was considered as a baseline. SPACSYS was first calibrated and validated with the data of the Broadbalk continuous winter wheat experiment for over a century. Six treatments were used: no fertiliser (control), a combination of chemical nitrogen, phosphorus and potassium with three N application rates (N1PK, N3PK and N5PK), manure only (FYM) and a combination of manure and chemical nitrogen application (FYMN). SPACSYS simulated grain yields and the dynamics of SOC and TN stocks well compared with the observations. Future climatescould significantly increase wheat yield by an average of 8.3% as compared to the baseline. FYMN was characterized by the highest grain yield. Moreover, when considering NPK practices, the relative increase in SOC stock under the RCP8.5 (+3.3%) was higher than those under the RCP4.5 (+1.4%), whereas the RCP2.6 indicated a negative effect (-0.6%) on SOC stocks. When considering manure amendments, the SOC stock decreased (-1.2%) under all RCP scenarios. However, continuous manure amendments can still be considered as a sustainable strategy for SOC sequestration with C stock increases between 34-106 kg C ha-1 yr-1. Future climates generally had positive effects on C sequestration in continuous wheat system with an annual C sink of 43-425 kg C ha-1 yr-1. Mineral fertiliser plus manure could be recommended as a good practice for simultaneously increasing crop productivity and having a rather high C sink under future climate change. 
Paleostress evolution in the South Pyrenean fold and thrust belt based on the structural analysis of fractures and U-Pb dating of carbonates
Authors: Cruset David , Muñoz-López Daniel , Vergés Jaume , Travé Anna
Published: February 2023

Structural analyses of vein and faults related with the growth of the South Pyrenean fold and thrust belt are coupled with the U-Pb ages of fracture-filling calcites compiled in Cruset et al. (2020) and Muñoz-López et al. (2022). Fractures include conjugated vein systems and reverse, strike-slip and normal faults cemented by calcite. The results reveal the orientation of tectonic stresses during the Pyrenean compression and their spatial and temporal evolution since the Late Cretaceous. Late Cretaceous to late Palaeocene U-Pb dates between 70.6 and 55.3 Ma registered compressional deformation in the inverted Mesozoic salt-related extensional basins corresponding to the Bóixols and Upper Pedraforca thrust sheets. Calculated paleostresses show a predominant N-S direction of tectonic transport, with more pronounced NW-SE directions in the western termination of the Bóixols and in the northern sector of the Upper Pedraforca.Fracture data and U-Pb ages between 47.9 and 42.3 Ma measured in the Lower Pedraforca thrust sheet reveal N-S and NW-SE directions of tectonic transport during the middle Eocene, similar to those in the Bóixols and Upper Pedraforca thrust units. Contrarily, younger late Eocene to Oligocene U-Pb ages between 36.2 and 28.4 Ma measured in the lowermost Cadí thrust sheet reveal an homogeneous N-S trend during the emplacement of this unit.Fractures cutting the Bóixols and Upper Pedraforca thrust sheets, and filled with cements yielding U-Pb ages from 48.8 to 25.68 Ma, show the same directions of tectonic transport than those measured for the Late Cretaceous-Paleocene. These Eocene and Oligocene ages also register the post-emplacement deformation of upper tectonic units on top of the Lower Pedraforca, Cadí, Montsec and Serres Marginals lower thrust sheets.This research was funded by the project ALORBE (PIE-CSIC-202030E310), DGICYT Spanish Projects PID2021-122467NB-C22 and PGC2018-093903-B-C22 Ministerio de Ciencia, Innovación y Universidades/Agencia Estatal de Investigación/Fondo Europeo de Desarrollo Regional, Unión Europea. David Cruset acknowledges the Spanish Ministry of Science and Innovation for the "Juan de la Cierva Formación” contract FJC2020-043488-I AEI/10.13039/501100011033.ReferencesCruset, D. et al., 2020. Quantifying deformation processes in the SE Pyrenees using U-Pb dating of fracture-filling calcites. Journal of the Geological Society, 177: 1186-1196.Muñoz-López, D., et al. 2022. Spatio-temporal variation of fluid flow behavior along a fold: The Bóixols-Sant Corneli anticline (Southern Pyrenees) from U–Pb dating and structural, petrographic and geochemical constraints. Marine and Petroleum Geology, 143: 105788.
Soil hydraulic conductivity defines minimum Root:Shoot surface ratio in moisture-limited environments
Authors: Javaux Mathieu , Cecere Andrea , Delval Louis , Wankmüller Fabian , Carminati Andrea
Published: February 2023

In drying soils, root water uptake is limited by the low soil hydraulic conductance. The magnitude of this conductance drop and its temporal dynamics are function of soil texture, soil water status, root hydraulic architecture, atmospheric demand and canopy conductance.  Under dry climates, in order to survive, plants can adapt their carbon allocation by maximizing their root:shoot surface ratio, thereby decreasing their transpiration surface while increasing their root surface.Thanks to a simple soil-plant hydraulic model, we show that soil hydraulic conductivity controls the minimum root:shoot surface ratio. A meta-analysis of shoot:root surface ratio is combined with a database of soil hydraulic properties to demonstrate how the minimum root:shoot surface value changes with soil conductivity across soil textural classes for dry biomes. We discuss the mechanisms by which plants can control their carbon allocation in such conditions and investigate the sensitivity of this minimum root:shoot surface ratio to future shifts in evaporative demand.
A non-stationary gridded weather generator conditioned on large-scale weather circulation patterns for Central Europe
Authors: Nguyen Viet Dung , Vorogushyn Sergiy , Nissen Katrin , Merz Bruno
Published: February 2023

For many flood risk assessments at large spatial scales, long-term meteorological data (e.g. precipitation, temperature) with spatially coherent representation are needed. This is where a regional weather generator comes into play. Meteorological fields for a specific region are strongly dependent on weather circulation patterns (CP) at larger scales. Additionally, there is evidence that these fields covariate with the average regional surface temperature (ART). With future climate change, such changes in both CP and ART should be included in weather generators.This study presents the development of such a non-stationary gridded weather generator conditioned on large-scale weather circulation patterns for Central Europe. The reanalysis dataset ERA5 (1o x 1o) is used for weather type classification. The E-OBS gridded observational dataset (0.25ox 0.25o) is used to parameterize the meteorological fields, such as precipitation and temperature (minimum, maximum, average). The spatial and temporal dependence is represented by the multivariate auto-regressive model. Daily precipitation amount is modelled by the extended generalized Pareto distribution and daily temperature is modelled by the transformed normal distribution. Both fields are conditioned on CP and allow to covariate with ART. In this way, the regional weather generator is capable of capturing “between-type” and “within-type” climate variability and can be used to generate long synthetic data for flood risk assessment in present and future periods.
Elemental and isotopic composition of silver in selected peat profiles of the Czech Republic
Authors: Mihaljevič Martin , Vaněk Aleš , Vaňková Mária , Ettler Vojtěch
Published: February 2023

Silver content and isotopic composition were studied in 3 selected 210Pb-dated profiles of ombrotrophic peat bogs in the Jizera Mountains, Ore Mountains and Sumava. The individual peat bogs differ in the rate of peat accumulation and intensity of immission load.All peat bogs show a peak in the 1970s, which is related to the peak of industrial production in Europe and the associated coal burning. This peak is found at a depth of 7-12 cm in the peatlands studied.In peat bogs in the Jizera and Ore Mountains, a smaller peak at a depth of 22-25 cm is followed by a peak in Pb concentration, probably related to Ag metallurgy in the 17th century.  This peak is not evident in the Šumava profile, where it is suppressed by elevated Ag concentrations in the underlying rocks.The individual sources of silver are documented by isotopic composition that appears in the studied geochemical archives.
The use of snow fences for snow conservation
Authors: Crivelli Philip
Published: February 2023

With ongoing climate change, residual snow in the mountains is disappearing ever earlier each year. This reduces their potential to be used as a water source later in the year. Especially for infrastructures like mountain huts, this can lead to severe problems. Our study describes how to actively apply the basics of snowdrift fences as snow-farming to establish snow depots as summer water source. This project asses how drifting snow can be applied in a practical and sustainable way in alpine terrain without the use of snow-groomers or snow-cannons.Existing, scientific models of snow transport are utilized in conjunction with the fundamentals of snow fence design to maximize the yield of residual snow in complex alpine terrain, contributing to water supply security. The study presents the results and approaches to the implementation of CFD modelling integrating meteo and snowpack models to analyze mountain terrain for potential sites. These results form the basis for the use of snowdrift fences to increase water storage in mountain regions.
An African-wide map of tree cover at individual tree level
Authors: Reiner Florian , Brandt Martin , Tong Xiaoye , Kariryaa Ankit , Fensholt Rasmus
Published: February 2023

The consistent monitoring of trees both inside and outside of forests is key to mitigating climate change. However existing large-scale tree cover maps primarily quantify forest cover and do not include isolated trees, as these are not discernible in lower resolution satellite images. In many dryland countries these non-forest trees constitute the main form of tree cover, and play a vital role in ecological stability, local economies, livelihoods, and food security.Here we make use of the PlanetScope nanosatellite constellation, which delivers global very high-resolution daily imagery, to map both forest and non-forest tree cover for continental Africa using images from a single year. We composite 232,053 4-band scenes from 2019 into 1x1° mosaics and apply a Convolutional Neural Network to segment canopy cover of all trees and shrubs. To train the network we use a combination of manually annotated 1 m labels and source images upsampled from 3 m to 1 m, resulting in a final model that maps tree cover at 1 m across the continent, segmenting closed canopies in forest areas and individual scattered trees in savannah areas.Our prototype map demonstrates that a precise assessment of all tree-based ecosystems is possible at continental scale, and reveals that 29% of tree cover is found outside areas previously classified as tree cover in state-of-the-art maps, such as in croplands and grassland. This analysis lays the groundwork towards global scale studies of tree cover at individual tree level and annual temporal scale, which is crucial for improved managing of woody resources, monitoring of TOF in relation to agroforestry, tree planting and restoration efforts, and assessing land use impacts in non-forest landscapes.
Dynamic topography and satellite gravity data joint inversion using Reduced Order Models (DYGIRO)
Authors: Ortega-Gelabert Olga , Fullea Javier , Arnaiz-Rodríguez Mariano S. , Zlotnik Sergio
Published: February 2023

Geophysical observables, such as surface elevation, gravity field anomalies, seismic data, surface heat flow, etc, are essential pieces of information used to make inferences about the structure and dynamics of the Earth’s interior. Simultaneously fitting different observable datasets is crucial in order to obtain consistent models. Among geophysical data, gravity data from ESA’s GOCE satellite mission provides key information in properly constraining the Earth’s density distribution. WINTERC-G is a new global thermochemical model of the lithosphere and upper mantle (currently being extended into the transition zone and lower mantle) based on terrestrial and satellite gravity data (Fullea et al., 2021). The inversion procedure behind WINTERC-G has two main steps. In step 1, a 1D column-wise inversion of surface wave tomographic, surface elevation (isostasy) and heat flow data is performed. Then, in step 2, the output model from step 1 is used as prior information for the inversion of the gravity field data (filtered geoid anomalies and gravity gradients from GOCE at satellite height) to refine the 3D crustal density and upper mantle composition. The model predicts a residual, non-isostatic topography that can be considered as a proxy for dynamic topography.
However, within a rigorous framework, dynamic topography cannot be simply taken as a non- isostatic residual, but it should be explicitly computed (i.e. solving the Stokes equation for a given rheological and density distribution) and consistently integrated into the joint inversion of the gravity field and the terrestrial observation with feedback from both the static and dynamic parts. The goal of DYGIRO project is to add a third step into the global WINTERC-G inversion scheme that consistently integrates dynamic topography as an additional model constrain.
We present here the first steps of such integration at global scale. To do that, the dynamic topography is computed by solving the Stokes flow problem associated with the current WINTERC-G model down to the transition zone. The dynamic topography thus obtained is coupled with the static thermochemical model constrained by gravity and seismic data within an iterative scheme where the observed surface elevation coincides with the model’s isostatic plus dynamic elevation contributions. The high computational cost associated with the large- scale 3D flow computations will be alleviated by means of Reduced Order Models. Such models are based on the idea of creating surrogate models that approximate the solution at a much lower computational cost.
 
Fullea, J. Lebedev, S., Martinec, Z., Celli, N. L. (2021). WINTERC-G: mapping the upper mantle thermochemical heterogeneity from coupled geophysical-petrological inversion of seismic waveforms, heat flow, surface elevation and gravity satellite data, Geophysical Journal International, 226(1), 146–191.
Aquatic scientists under water - it’s much more than just fun
Authors: Fischer Philipp , Brand Markus , Comeau Steeve , Schmid Michael , Schwanitz Max
Published: February 2023

Aquatic research is often recognized as the last real adventure with dedicated scientists sailing on famous research vessels to even remotest areas like the Arctic or Antarctica taking samples with highly sophisticated scientific equipment. Such cruises or even more, scientists in submarines or ROVs are eye-catchers and get a high level of attention in the scientific, public and political community. In contrast, there is a comparatively small group of scientists which indeed physically enter the aquatic ecosystem and do science there - the group of diving scientists.  Most surprisingly, this small group of scientists is sometimes not well recognized in science. Very often, scientific divers are assumed to take up their hobby and have mainly fun under water instead of doing serious scientific work. We - the scientific diver community - are often confronted with statements like “oh, you can be outside and can dive the whole day long, I have to stand the entire day in the lab. Your work must be like holydays”. Most of these colleagues have never been out the entire day in a bulky drysuit, spending hours and hours on a small boat while the colleague is under water doing fine tuned work in the three-dimensional space having the air to survive in tanks on the back. Often these colleagues have never spend 6 or more hours outside in a steady swell or with outside temperatures below 0°C of above 30°C and 100% humidity - without a private toilet - on a 6 m long RIB-boat.In this talk, we present the well harmonized European standards for doing excellent science under water, the respective European and German national bodies for scientific diving, as well as the required and recommended occupational safety standards and procedures for a successful, safe and efficient scientific work under water. In contrast, we also stress some possible reasons why doing science under water as diving scientist is, most  surprisingly, much less accepted and established in science as doing aquatic science from “outside”, e.g. from a ship floating at the surface.
37Cs transport flux to surface water due to shallow groundwater discharge from forest hillslope
Authors: Niwano Yuma , Kato Hiroaki , Akaiwa Satoru , Anderson Donovan , Iida Hikaru , Nakanishi Miyu , Onda Yuichi , Sato Hikaru , Niizato Tadafumi
Published: February 2023

Groundwater systems and surface water can interact in a complex manner that influences catchment discharge, which then becomes more complex in forest slopes. A large amount of Radioactive cesium (137Cs) deposited on forests due to the Fukushima Daiichi Nuclear Power Plant accident remains in terrestrial environments and is transported downstream as suspended or dissolved forms by surface water. Generally, the concentration of dissolved 137Cs in surface water increases especially during runoff. While the leaching behavior of 137Cs from contaminated forest materials and soils to surface water has been heavily studied, the influence of 137Cs concentration in shallow groundwater systems in forest slopes have not been investigated. Therefore, detailed hydrological observations of groundwater on a forest hillslope will enable quantitative analysis of the influence of groundwater flow on the formation of dissolved 137Cs concentrations in surface water during base flow and during runoff. Our results showed that the dissolved 137Cs concentration in surface water increases during water discharge. The average concentration of dissolved 137Cs in shallow groundwater was 0.64 Bq/L, which was higher than that in surface water (average 0.10 Bq/L). Furthermore, it was also observed that a part of the shallow groundwater on the slope moves toward the river channel at the time of water runoff. This suggests that shallow groundwater may have flowed into the surface water during the outflow and contributed to the increase of 137Cs in the surface water. In this study, the contribution of groundwater in forest slopes to the dissolved 137Cs concentration in surface water was estimated using the hydrodynamic gradient distribution of groundwater in forest slopes and the measured dissolved 137Cs concentration in groundwater.
Possible Role of Fluctuation Excitation in the Formation of Alfvénic Fluctuations Originating from Interchange Magnetic Reconnection
Authors: Hou Chuanpeng , Rouillard Alexis , He Jiansen , Gannouni Bahaeddine , Réville Victor
Published: February 2023

Parker Solar Probe has detected abundant magnetic inversions and velocity spikes in the young solar wind, the origins of which are still highly debated. Numerous studies based on observational data and numerical simulations favor the causal correlation between interchange magnetic reconnection process and these velocity spikes. However, the specific process by which interchange magnetic reconnection leads to these structures is still inconclusive. Interchange reconnection should occur during the eruption of small bipoles in pre-existing open magnetic field regions such as coronal holes. This process is known to drive the formation of plumes and pseudo-streamer like structures and potentially mesoscale structures measured in the solar wind as well as velocity spikes. Using velocity measurements from Solar Orbiter we infer the magnetic origin of mesoscale structures and velocity spikes measured by Solar Orbiter, we find that the footpoints of the magnetic lines associated with these spikes are located at the boundary of a coronal hole observed by the Solar Dynamics Observatory (SDO), where the interchange magnetic reconnection is likely to occur. The imaging instruments aboard Solar Orbiter and SDO record one typical interchange magnetic reconnection event near the footpoints. With the high temporal/spatial resolution images obtained from multiple perspectives, we directly analyze the fluctuating motion of jet flow materials and explore the mechanism of fluctuation excitation during the interchange magnetic reconnection. We compare our observations with a 2.5D MHD simulation of interchange magnetic reconnection, we speculate that outward fluctuations may act as a kind of mediator between interchange magnetic reconnection and the formation process of velocity spikes/magnetic switchbacks.
The impact of land subsidence and mitigating measures on near-surface groundwater salinities at the south bank of the Nabaki River, Japan
Authors: Tsai Chi San , Liu Jiaqi , Ito Yuka , Tokunaga Tomochika
Published: February 2023

Land subsidence is mainly caused by over-exploitation of groundwater, and it has been resulting in several problems along the coastal areas in Japan such as damages to buildings and facilities, changes of stream slopes, and increased risks of river flooding during high tides or storm surges. At the south bank of the Nabaki River in the Kujukuri coastal plain, Japan, some inland areas have become below the mean sea-level due to land subsidence. To prevent flooding in these areas, the local authority has constructed pumping stations and ditch networks at both sides of the tidal river since 1960s. The former can discharge the unnecessary water out to keep the land surface areas dry while the latter contributes to the agricultural productions by efficiently discharge water out. However, the pumping and discharging behaviours result in lowering groundwater levels that may cause further seawater intrusion. Here, a numerical model was developed by using the HydroGeoSphere code to investigate how the land subsidence and mitigating measures affect the quality of near-surface groundwater resources. The model solved coupled surface-subsurface flow and mass transport processes with the variable-density effect. Different scenarios were designed to compare the situations with and without land subsidence and pumping activities. The simulation results showed that, although the pumping stations and ditch systems performed effectively for preventing flooding associated with land subsidence, this system can enhance seawater intrusion to the inland aquifer from the tidal river. The results suggest that the pump stations and ditch systems built for preventing floods in subsidence areas should be carefully evaluated for their potential impacts on the groundwater flow regime and water quality. 
Unravelling the „capacity-action-gap”: An exploration of the difficult role of adaptive capacity in explaining the uptake of private flood risk adaptation measures
Authors: Schubert Annika , von Streit Anne , Garschagen Matthias
Published: February 2023

Residents are increasingly expected to take adaptive actions to reduce risks and to strengthen resilience in the case of extreme events, like floods (e.g. Begg et al., 2017). In recent years, the focus of flood risk management (FRM) has shifted from structural, mainly government-led interventions, to more integrated approaches which stress the responsibility of households to protect themselves from flood damages (Kuhlicke et al., 2020). However, especially in the case of pluvial flooding, the uptake of measures at the household level is still low. To appraise the adaptive behaviour of households, research typically uses adaptive capacity as the main proxy (Grothmann & Reusswig, 2006; Mortreux et al. 2020). However, it is increasingly clear that high levels of adaptive capacity do not necessarily lead to high levels of private adaptation (Mortreux et al. 2020). A better theoretical and empirical understanding of the gap between adaptive capacity and action is therefore urgently needed.This paper, therefore, addresses the following questions:(1) What kinds of measures are (not) taken by what kind of households?(2) What are the most decisive factors explaining why households become active to protect themselves?(3) How are the taken measures related to the adaptive capacity of households?Our study is based on a survey conducted in early 2022 with 1,615 households in a region in Upper Bavaria (Oberland region), Germany, which is heavily affected by increasing floods. Being one of the most affluent and dynamically growing regions in Germany, the adaptive capacity of households and communities is comparatively high. Yet, adaptation action remains at a rather low level. Therefore, the study region forms an excellent test case to investigate a possible “capacity-action gap”. By means of descriptive statistics and regression analysis, different sets of private measures (building measures and insurance uptake) are linked to household profiles. Thereby, exposure, vulnerability, and different dimensions of the adaptive capacity of the household are taken into account. Our results indicate a “capacity-action-gap” (Schubert et al., forthcoming). In fact, variables such as property ownership, risk awareness and previous flood experience have far more explanatory power whereas classical adaptive capacity indicators such as education and income only serve as proxies for a few related variables (e.g., property ownership and coping capacity).With these insights into households’ practices and perceptions, we want to contribute to a more nuanced and critical discussion on the trend of individualizing responsibilities in FRM. Thus, the question is how to achieve a resilient society in the coming years, if even those households which are endowed with sufficient resources cannot be expected to adapt out of their own free choice and on their own.
Active anticline and backthrust override a geological thrust: evidence from present and Holocene deformation rates within the foothills of southwestern Taiwan
Authors: Le Béon Maryline , Shih Jhih-Wei , Chen Chang-Chih , Huang Wen-Jeng , Tseng Ya-Chu , Chiu Yi-Wei , Liu Yen-Chiu , Hsieh Meng-Long , Lu Chih-Heng , Pathier Erwan
Published: February 2023

In the classical evolution of a fold-and-thrust belt, the deformation front progressively propagates basin-ward and the activity of the newly developed structures modifies the geometry and, likely, the kinematics of the existing structures located on their hanging wall. The Taiwan mountain belt sits at the convergence boundary between the Luzon volcanic arc and the Chinese continental margin. The 8-cm/yr westward shortening across the island is partly accommodated at the western piedmont of the orogen by a series of folds and thrusts trending about N30˚E. This study investigates the Holocene activity of a geological structure located within the foothills of southwestern Taiwan. At this latitude, GPS observations indicate about 2 cm/yr of westward shortening across a 20-km-wide zone. The targeted geological structure is located about 12 km east of the deformation front. It includes, from west to east, a tight upright anticline, the Wushantou anticline, with early Pleistocene mudstone at the anticline axis, a significant thrust fault with a steep dip to the east, the Lunhou fault, that brought early Pliocene strata against Pleistocene strata, and an active west-dipping backthrust with limited total offset, the Kouhsiaoli fault. These structures are crossed over by the Tsengwen River. A flight of 11 Holocene river terraces was dated from 10 ka to 2 ka using radiocarbon dating. The highest terrace locates near the anticline fold axis and lies 140 m above the modern river. We determined bedrock incision rates across the investigated structure and accounted for sedimentation rates in the Holocene foreland basin to determine uplift rates that evolve from 5-7 mm/yr west of the anticline to 15-20 mm/yr from the anticline axis to the Kouhsiaoli backthrust, and decreasing to 5-7 mm/yr east of the backthrust. Present deformation observed by InSAR indicates a similar deformation pattern. These suggest that the backthrust and anticline are the main active structures at least since the early Holocene and that the major geological thrust has likely been inactive during this time period. On-going works are focused on the deep geometry of these geological and active structures, on the partition of shortening between the anticline and the backthrust and on how the entire structure may have evolved as deformation propagated westward.
Using secondary currents induced by air curtains to improve trapping of plastic particles
Authors: Lage Ferreira Rui , Restrepo Steven , Ricardo Ana
Published: February 2023

Plastic waste is ubiquitous in aquatic environments. It has become an environmental and societal problem due to its fragmentation into microplastic particles. We analyze the potential of secondary currents induced by air curtains to i) drive plastic particles into river lateral retention basins and ii) increase the probability of permanent retention in the sediment bed. Plastic particles simulate macroplastics, with h/d = 100, where d is the diameter of the plastic particle and h is the flow depth.   

We mapped the efficiency of retention (percentage of mass of plastic particles permanently retained) to flow, air curtain and basin parameters. The latter are the Froude number, dimensionless air mass flux, basin aspect ratio and normalized plastic load. Measurements included Laser Doppler anemometry to map the flow field, LSPTV to track plastic particles.

We have found that the secondary currents induced by air curtains can increase the plastic retention time in zones with separated flow. However, the absolute increase in permanent retention is low. Permanent retention seems only possible if vegetation or human-made structures are present in the retention zone. This combination should constitute a scalable retention solution employing cost-effective techniques, with low impacts on the biota and a low carbon footprint.

Acknowledgements: This work was partially supported by Foundation for Science and Technology's through funding UIDB/04625/2020 (CERIS research unit).
Irrigation Schedules for Wheat Crop and Water Saving
Authors: Upreti Hitesh , Ojha Chandra Shekhar Prasad
Published: February 2023

Agricultural water takes more than 70% of the available water resources, globally and wheat is one of the most widely grown and irrigated crops in the world. Keeping the ongoing and predicted global water scarcity, water saving in agriculture is very critical for the food and water security nexus. Therefore, controlled field experiments on wheat have been carried out at Indian Institute of Technology, Roorkee, India for 2014-15 and 2016 seasons. The aim is to arrive at optimum irrigation schedules for wheat crop grown in sandy-loam soil which will result in water saving without affecting the grain yield considerably. The experimental setup includes four experimental field plots in which wheat crop is grown. Soil water content of the field plots are regularly monitored. Irrigation schedules of the four field plots are varied by irrigating at different soil moisture depletion (SMD) levels: 0-20% SMD (fully irrigated), 40% SMD, 50% SMD and 60% SMD, thus varying the timing and amount of irrigation. Irrigation at 50% SMD is observed to irrigation schedule with highest water productivity for the wheat crop in sandy-loam soil after comparing the grain yield and irrigation values for two cropping seasons. There was a decrease of 6.9% and 2.3% in grain yield of 50% SMD irrigation treatment when compared to the fully irrigated treatment. 50% SMD treatment has the highest water productivity of all the irrigation treatments with values of 17.34 kg/ha-mm and 14.1 kg/ha-mm for two crop seasons while values of water productivity for the fully irrigated treatment are 13.29 kg/ha-mm and 11.14 kg/ha-mm.  50% SMD treatment resulted in water saving of 26.4% and 25.2% of water saving for the two cropping seasons 2014-15 and 2016, respectively when compared to the fully irrigated treatment for per unit water usage. A substantial decline in grain yield of 60% SMD irrigation treatment points out that irrigation should be applied in the wheat crop at a maximum soil moisture deficit of 50%.
Novel perspectives in transport infrastructure management: Data-Fusion, integrated monitoring and augmented reality
Authors: Gagliardi Valerio , Bianchini Ciampoli Luca , D'Amico Fabrizio , Calvi Alessandro , Benedetto Andrea
Published: February 2023

Infrastructure networks are crucial elements to ensure the sustainability of the current development model in which the movement of people and goods is essential. On the other hand, transport assets are increasingly exposed to several issues, including climatic conditions changing, vulnerability and exposure to natural hazards such as hydraulic, geomorphological, landslides and seismic phenomena, which can affect the structural integrity causing damages and deteriorations. The context is made even more serious by the degradation of materials and the progressive ageing of infrastructure, often accelerated by environmental conditions and inadequate, or not always effective, maintenance actions. This requires the investigation of novel methods for the large-scale detection of network-scale linear infrastructures, and simultaneously, of detail to diagnose causes and determine the priorities for the most effective countermeasures.
The proposed solution is based on a Data-Fusion approach, merging data coming from multi-source and multi-scale data, to enhance the interpretation process in a holistic sense. The information comes from spaceborne Multi-temporal SAR Interferometry, complemented by more detailed aerial data, detected by UAVs and Ground Based Non-Destructive Testing Methods, including laser scanner surveys for resolution and digital integrability, high-resolution camera measurements assisted by artificial intelligence for the surface degradation and from prospecting data collected by Ground Penetrating Radar technology. All these data can be simultaneously analyzed into a comprehensive digital platform, providing a useful tool to support operators and public bodies to prioritize maintenance actions.
The digital platform can be investigated also using augmented reality tools, capable of generating and reproducing the Digital Twin of the inspected infrastructure into a real environment. This allows any monitoring evaluation through a diagnostic technique that integrates spatial, aerial, ground-based and geophysical surveys, allowing navigation within the infrastructure. Potential applications are numerous, ranging from mapping of wide areas affected by potential criticality to the definition of the main vulnerabilities related to the seismic and hydraulic risks, the analysis of land changes surrounding the assets following extreme natural events, and the reconstruction of historical deformative trends of roads, railways and bridges through the interpretation of SAR data.
Acknowledgments
This research is supported by the Italian Ministry of Education, University, and Research under the National Project “EXTRA TN”, PRIN2017, Prot. 20179BP4SM. In addition, this research is supported by the Project “MLAZIO” funded by Lazio Region (Italy).
Peat respiration in drained peatland forests under varying tree harvest regimes
Authors: Korrensalo Aino , Anttila Jani , Jauhiainen Jyrki , Laiho Raija , Lehtonen Aleksi , Mäkiranta Päivi , Ojanen Paavo , Peltoniemi Mikko , Penttilä Timo , Salovaara Petri , Mäkipää Raisa
Published: February 2023

About 15 million ha of peatlands has been drained for forestry to increase the volume of aerobic peat available for tree roots. Simultaneously, the peat that was earlier in anoxic conditions has become available for aerobic decomposers, resulting in increased CO2 emissions through respiration. To mitigate these CO2 emissions a proposed solution is to switch from clearcuts to continuous cover forestry targeting to regulate water table (WT) with tree stand evapotranspiration and maintain an optimum WT low enough for tree growth and high enough to protect peat from decomposition. However, it is yet unknown how tree stand volume and site properties interact in controlling WT and peat decomposition.

We aimed at quantifying the effect of tree harvest intensity on WT and heterotrophic peat respiration (RHP) at seven drained peatland forests of varying fertility. We conducted chamber measurements of RHP at plots where autotrophic root respiration was excluded by trenching and the respiration of mosses and fresh litter was excluded by temporarily removing the upmost 5 cm soil layer before the measurements. Seasonal RHP measurements were conducted up to nine years after tree harvesting, with intensities varying from clearcut to different selection harvest regimes and unharvested controls.

Unharvested controls had an average WT depth of about 50 cm, which rose after tree harvesting with the largest increase of 22 cm observed in clearcut sites and a smaller effect found in the selection harvest treatments. The highest RHP rates of 307 mg m2 h-1 were measured at the most nutrient rich site types. Although deeper WT in general increased RHP, tree harvest intensity had only a limited impact on RHP. This suggests that although WT depth of drained peatland forests can be regulated with the tree stand volume, the resulting shallower WT may still be too deep to markedly reduce RHP.
Ozone in a stratospheric aerosol injection scenario
Authors: Jörimann Andrin , Chiodo Gabriel , Vattioni Sandro , Sukhodolov Timofei , Tilmes Simone , Visioni Daniele , Plummer David , Morgenstern Olaf
Published: February 2023

Stratospheric aerosol injection (SAI) holds the potential to offset some of the future warming of the Earth’s surface. It comes with many potentially dangerous side effects, however, which are currently not well understood and poorly constrained. A major concern is the effect on stratospheric ozone, which could be weakened and delayed in its recovery, given that ozone-depleting substances will take decades to be completely removed. We are interested in ozone depletion and recovery in a scenario, where SAI is employed to keep the global surface temperature constant. Previous analyses have been conducted with models that have widely different treatments of aerosol microphysics and chemistry. To isolate and estimate the uncertainty of the chemical and dynamical effects in a multi-model context, CCMI-2022 proposed a new senD2-sai experiment, where the ocean is kept fixed and the elevated stratospheric aerosol burden, thus, only affects the middle atmospheric composition and temperature. Stratospheric aerosols are also uniformly prescribed for all participating models in order to minimize the uncertainty arising from the treatment of aerosol microphysics. In our work, we perform these experiments with our aerosol-chemistry-climate model SOCOLv4.0, and compare our results with other CCMI-2022 models, with a focus on the stratospheric ozone and temperature changes. We evaluate the role of individual processes, such as ozone destruction cycles and changes in large-scale transport. In addition, we discuss implementation issues related to imposing this aerosol forcing, as this will help in the interpretation of the main inter-model uncertainties. Finally, we discuss the implications of this work for our understanding of chemical feedbacks in future climate in the context of mitigation via SAI, and its relevance for future ozone assessments.
Aseismic rupture on rate-weakening faults before slip instability
Authors: Ray Sohom , Garagash Dmitry I.
Published: February 2023

The nucleation of earthquakes relies on an interfacial instability that facilitates the transition of a slow fault slip to a faster dynamic rupture. Here, we highlight the scenarios when (rate-weakening) interfaces exhibit a phase of slow aseismic rupture—before slip instability—that propagate large distances compared to the usual nucleation sizes. This aseismic rupture propagation results from rate-weakening interfaces' response to reach a state of steady sliding when forced to slip below steady-state frictional conditions. We numerically simulate the slip cycle—aseismic rupture, instability, and dynamic rupture—driven by prototype loading configurations:Slip dislocation accrues at a constant rate at one end of a finite fault with the other end (a) at the free surface of an elastic half-space and (b) completely locked (buried) in an elastic full-space.
Imposed slip dislocation accruing at a constant rate on both ends of a finite fault
A localized distribution of shear traction that increases at a constant rate.
All the above loading conditions can permit a slow aseismic rupture along the fault when the fault is initially locked: a state of interfacial slip for which the frictional strength, at the current slip rate, is significantly less than the steady-state frictional strength at the same slip rate. The slow rupture occurs in all the above loading configurations when the fault is initially locked; the subsequent transition to instability, or not, shows a fault-size dependence for configurations 1a and 1b, even when the fault exceeds the usual nucleation sizes. The cut-off fault size that permits instability after aseismic rupture also depends on the friction parameters, the extent of initial contrast from steady-state sliding, and slip conditions towards which aseismic rupture progresses. The remaining loading configurations exhibit instability whenever the fault size exceeds the usual nucleation sizes. Further, we find that slow rupture’s transition to early-stage instability happens through an intermediate breathing (spatiotemporal oscillation) type evolution of slip rate.
The role of reservoir operation in sediment contribution to water quality: an spatiotemporal scale analysis along the Guadalquivir river
Authors: Contreras Eva , García Guillermo Salvador , Polo María José , Pimentel Rafael
Published: February 2023

In Mediterranean areas, where water scarcity is a common and recurrent problem, reservoirs play a key role in water resources management. Water allocation for different uses (e.g., urban, agricultural, hydroelectric, and ecological) can be affected by numerous external and internal factors limiting  their water quality condition in the reservoir and in the downstream areas. On the one hand, the loads of substances that alter water quality standards (e.g., sediments, nitrogen, phosphorus). On the other hand, the influence of the management and operation of the reservoir affects the streamflow natural regime. An example of these effects is found in the Guadalquivir river basin (Southern Spain), a highly regulated basin (113 reservoirs) with a relevant problem of sediment inputs throughout the river. The high sediment load is a consequence of the existence of high rates of erosion, favored by the complex orography, the high slopes, the extreme rainfall and the land uses, which partially or totally expose the surface of the land (e.g., olive groves). In this context, the objective in this work is to assess how water quality dynamics are affected by the management and operation of the Guadalquivir’ reservoirs system.Historical information available for the study period 2011-2022 in 9 control points located in the Guadalquivir river and the main contributing subbasins was compiled,  including: 1) inflow, outflow, stored water volume and precipitation data in reservoirs on a monthly and daily basis, and 2) suspended solids concentration data on a monthly and hourly scale, all of them provided by public regional government data networks.As result, the sediment loads received by the reservoirs located in the main axis of the Guadalquivir were estimated at daily, monthly, and annual time scales, showing direct relationships with water inputs. Two different scenarios depending on discharges and precipitation in the contributing subbasins were found to cause different effects in water quality: ordinary operation scenario and flood operation scenario. Therefore, the combined  understanding of the operational (discharges) and natural (rainfall events) drivers constitutes a relevant step for the effective, efficient, and sustainable management of water resources in reservoirs contributing to one of the challenges of society to comply with the Water Framework Directive in the current context of global warming.Acknowledgements: This work has been funded by the project Integrated Management for the control of water inputs and sediments in reservoir systems in the Guadalquivir basin, with the economic collaboration of the European Funding for Rural Development (FEDER) and the Office for Economy, Knowledge, Enterprises and University of the Andalusian Regional Government.