bluuebunny/crossref_metadata_2025 huggingface dataset:
A 130-year history of avalanche risk in the Fagaras Mountains, Romanian Carpathians deduced from interference with human activities
Authors: Voiculescu Mircea , Torok-Oance Marcel , Bodea Diana
Published: June 2022

Snow avalanches are a denudational process and natural hazard that can severely damage tourist infrastructure, roads and forests and lead to injury and loss of life. Political and socio-economic changes in mountain landscapes also affect avalanche activity. This study was carried out in the Făgăraş Mountains, a representative mountain unit in the Southern-Romanian Carpathians, which is dominated by glacial and periglacial relief, high altitudes, high snow cover thickness, snow persistence of about 8-9 months per year and high occurrence of avalanche hazards.

Our analysis of the location, spatial extent and number of avalanche events was based on extensive documentation using old photographs, maps, papers and statistics from Mountain Rescuer Public Services databases. We also used dendrogeomorphological data with a 130-year chronology, from which we extracted the frequency, magnitude and spatial extent, satellite images and event simulations using the RAMMS avalanche module in the most affected area of the Fagaras Mountains, the Balea-Capra glacier sector. The study data were collected between 1880 and 2020, in three different periods, each with political and socio-economic peculiarities: the Romanian Kingdom Period (1880-1945), the Communist Period (1946-1989) and the Post-Communist Period (1990-present). In the first period, the tourist infrastructure was modest with no tourist traffic and the avalanche danger was not recognized. Only three avalanche events with human casualties were recorded. In the communist period 23 avalanche events were recorded. In the post-communist period, 75 avalanche events were recorded. Avalanche activity has strongly interfered with the emergence of new elements of tourist infrastructure such as huts, alpine refuges and the Transfăgărășan highway but also with the increasing exposure of tourists especially in the last 20 years. This is why the Făgăraş Mountains are a real avalanche hot spot in the Romanian Carpathians, accounting for 51.2% of fatalities and 57.4% of injuries/burials.

Studies carried out in the Romanian Carpathians have shown that climate warming is more evident between 1,000 and 1,500 m than at higher altitudes where most avalanches have been recorded. In this context, it is difficult to determine that the frequency and spatial extent of avalanches is determined by global change.

 
Integrating a drone’s DEM and orthomosaic enhances performance of Object-Based Image Analysis for habitat mapping of shallow coral reefs
Authors: Nieuwenhuis Brian Owain , Marchese Fabio , Benzoni Francesca
Published: June 2022

Shallow coral reefs are biodiverse ecosystems currently severely at risk from anthropogenic disturbance and climate change. To ensure their survival through the Anthropocene, ecologically informative maps of these areas, that can guide ecosystem-based management, are necessary. In recent years, Unmanned Aerial Vehicles (UAVs) have emerged as a new tool to obtain spatially explicit data of the benthic community in very shallow habitats (<3.5 m deep), where acoustic survey techniques used in deeper water become challenging or unfeasible. Structure-from-Motion (SfM) processing allows the conversion of separate images into high-resolution orthomosaics and Digital Elevation Models (DEM), spanning several hundred metres. The orthomosaic is commonly used to create a habitat map. Object-Based Image Analysis (OBIA), in which an image is first segmented into homogeneous segments before classification, provides an effective method to work with such high-resolution data. In this study we investigated the possibilities to enhance habitat classification by also using the DEM in the OBIA. Therefore, we surveyed three shallow reef areas on the central Saudi-Arabian coast with a consumer-grade UAV and processed the imagery with SfM. We then separately assessed the impact of adding the DEM’s three-dimensional information on the image segmentation and automatic classification steps in the OBIA. Integrating both the 3D model and spectral information into the segmentation greatly reduced the amount of oversegmentation. The addition of DEM-derived variables into a Random Forest classifier increased overall classification accuracy up to 11%. Thus, this study demonstrates the previously untapped potential of a drone’s DEM to improve the accuracy of semi-automated OBIA for habitat mapping in shallow tropical marine ecosystems.
Ancient Poliochni Geoarchaeological Research: Its proximity to the sea and the possible location of an ancient harbor (North Aegean Sea, Greece).
Authors: Vouvalidis Konstantinos , Kapsimalis Vasilios , Tsourlos Panagiotis , Koukousioura Olga , Almpanakis Konstantinos , Czebreszuk Janusz , Aidona Eleni , Doani Sofia , Vandarakis Dimitrios , Dimou Grigoria-Vasiliki
Published: June 2022

Ancient Poliochni is one of the oldest excavated cities in the Aegean Sea and its connection with the sea is indisputable and diachronic during the city habitation from 3500/3300 BC to 2000/1900 BC. The research focuses on the palaeogeographical evolution of the city valley, the coastal zone, and the nearshore seabed. On land, the study area is the lower part of the river valley located between the archaeological site and the foothills of the Agia Triada coastal hill. Data were acquired by geomorphological and geophysical research, drillings (up to 14.5 m depth) stratigraphical and paleontological analysis, and high accuracy topography using GNSS receivers and Unmanned Aerial Vehicles (UAVs). The marine survey extends to the entire Voroskopos (Poliochni) Bay including satellite image analysis, single-beam echo soundings, side-scan sonar seafloor detection and imaging, and visualization of special seabed features.

Ancient Poliochni was founded on a coastal terrace shaped by the erosive action of the waves on the hard formations of the Limnos Island geological basement. The seabed morphology and geology of the Poliochni Bay shows that it was part of the coast, during the city habitation, in a progressively flooded by the rising sea level coastal environment.
Soil transformations at the edge of the Pedregulho plateau, São Paulo, Brazil
Authors: Costa Adriana , Pagliaroni Eduardo , Oliveira Fabio
Published: June 2022

One of the most important issues in soil-landscape studies is the understanding of how pedological transformations in the slopes occur from the modification of the base level. Local and regional geomorphological processes, such as scarp retraction, drainage captures, modification of fluvial activity in water courses, etc., can lead to important fronts of pedological transformation. In this context, the pedological covers on the edges of plateaus are inserted, with emphasis on the cuestas. This study aimed to investigate the organization of soil cover on the edge of a basaltic-sandstone plateau, in the extreme northeast of the São Paulo state, between 1050 and 850m altitude, in the municipality of Pedregulho. Morphological descriptions and physical, chemical and mineralogical analyzes were performed on the five soil profiles, arranged in toposequence, from the top of the slope to the bottom of the valley. Two pedological compartments were identified. The most common is the latosollic compartment, which occurs from the top to the mid-slope, with the transition from the typical Dystrophic RED LATOSOL to the cambisolic Eutrophic RED LATOSOL. The other compartment is the neo-cambisollic, which occurs towards the base of the slope, with typical Eutrophic Cambisol and a small portion of typical Dystrophic Tb FLUVIC NEOSOL. This transition reveals that scarp retraction has accelerated erosive processes on the immediately affected slopes, and that morphogenetic processes has more intensy with soil genesis in the studied plateau. Thus, the pedological transformation from latosols to cambisols has been caused by erosion in the study area.
The COOL-DUNES project:  Factors controlling spatial patterns of periglacial dune fields in the central part of the European Sand Belt
Authors: Łopuch Michał , Jary Zdzisław , Lindhorst Sebastian
Published: June 2022

The influence of periglacial conditions on the development of aeolian bedforms is not well understood. Observations of active dune fields in polar regions show that they can develop as either consistent dune fields, similar to what is known from hot regions, or as isolated sand patches controlled by the ground-water table. However, modern periglacial dune fields are rare, hampering the investigation of the factors that control dune-field evolution in cold regions.

The aim of this project is to define factors controlling the spatial pattern of periglacial dune fields in the central part of the European Sand Belt. Methods will include high-resolution morphometry and GIS analyses, combined with ground-penetrating radar, granulometry, and quartz-grain morphoscopy in an integrated approach. Pleistocene dune fields located in Poland will serve as key areas for similar dune systems elsewhere. Results will be supported by detailed studies of individual dunes. The project will try to answer the questions about 1) the impact of periglacial conditions (seasonal variability in sand supply, patches of permafrost, high surface wetness) and morphological framework (topography, surface inclination, occurrence of morphological barriers) on the development of dunes and dune fields; 2) spatial differentiation of aeolian processes within European Sand Belt.

The scientific hypothesis to test is that dune fields in periglacial regions are controlled by high variability of local depositional conditions, which result in the coexistence of various dune types and weak spatial organization of dune fields.

Results will allow us to develop a model of periglacial dune field evolution. Data will not only shed new light on periglacial aeolian morphology, but will be also valuable for the analyses of climatic conditions at the end of the last glacial.

The project is funded by Polish National Science Centre, contract number 2021/41/N/ST10/00350.
The impact of strong precipitation and lithologic gradients on the evolution of post-eruption volcanic surfaces
Authors: O'Hara Daniel , Goren Liran , Campforts Benjamin , Kervyn Matthieu
Published: June 2022

Volcanic edifices are dynamic landforms whose morphology encodes the long-term (thousands to millions of years) interaction between construction and erosion. Short-term episodes of volcanic activity that cumulatively build topography compete with long-term erosive processes associated with climate and mass wasting to degrade edifices, generating a variety of morphologies from simple, cone-like edifices to complex, non-axisymmetric volcanoes. However, separating the signatures of these processes using topography remains elusive as both volcanic and climatic processes are often spatially-heterogeneous and temporally-varying. Despite this, disentangling edifice morphologic histories provide new avenues to better discern an edifice’s volcanic record, assess potential hazards, and quantify the role of climate in landscape evolution.

Here, we aim to understand the long-term interaction between volcanic and erosional processes in driving edifice morphology using numerical landscape evolution modeling and comparing modeled landscapes to the morphology of the Kaua`i shield volcano. Kaua`i has been built over the past 5 Myr by series of lava flows that have non-uniformly altered both topography and surface erodibility. Coupled with this, a strong precipitation gradient across the island has influenced basin-scale erosion rates, impacting drainage development and making Kaua`i a natural laboratory to test the effects of spatially- and temporally-varying construction and degradation processes.

We analyze the interaction of these processes by first characterizing the impacts of lithology and precipitation gradients on edifice morphologies over 5 Myr timescales by employing the TopoToolbox Landscape Evolution Model. Starting with an initial, simplified edifice geometry, we test the effects of both singular and multiple parameter gradients through space and time over a broad parameter space. We then quantify edifice degredation and evolution using a series of metrics that include topographic hypsometry, basin geometries, drainage density, and , showing that such parameter gradients create asymmetric landforms with spatial heterogeneities related to the geometry and configuration of basins and channel networks. Afterwards, we consider edifice morphologic evolution within the framework of Kaua’i. By constraining the spatiotemporal model parameter configurations with the geologic and precipitation data of the volcano, and comparing modeled landscapes to the current morphology of Kaua’i, we determine likely parameter ranges that contribute to its evolution.
Modeling bedrock channel erodibility as a function of measurable rock properties and climate
Authors: Johnson Joel , Guryan Grace , Anderson Sam , Gasparini Nicole , Tranel Lisa , Heimsath Arjun
Published: June 2022

Bedrock channel erodibility is a nonunique model-dependent parameter that scales hydraulic forcing to fluvial bedrock erosion. In landscape evolution modeling, erodibility coefficients are often assumed constant and uniform, and are often empirically calibrated to the form of natural landscapes. This approach lumps a wide range of variables into erodibility, including not only rock properties but also erosion processes (and their possible variations with discharge), climatic controls on hydrographs and rock weathering, and effects of coarse sediment supply.  Our goals are to better understand (a) how field measurements of rock properties could be combined to better quantify bedrock erodibility, (b) how bedrock erodibility may vary with discharge as different fluvial erosion processes become more or less dominant, and (c) how flood discharge variability and coarse sediment load influence “effective” erodibility in simple stream power incision model formulations.

Building on previous work, we first present new equations to calculate erodibility. Our rather complex erodibility model incorporates core-scale (i.e. unfractured) rock strength, discontinuity spacing (fractures, bedding planes), and climate-dependent bedrock susceptibility to weathering (which influences strength and fracturing), and accounts for abrasion and block plucking erosion processes. The model attempts to include feedbacks between these factors in a physical way, using variables that could be constrained from field data. Second, we explore the parameter space of these erodibility equations by modeling bedrock channel profile evolution for a range of conditions and varying rock properties, using preliminary constraints from field data collected in the semi-arid and lithologically variable Guadalupe Mountains, New Mexico and Texas, USA. Finally, we generalize our results by estimating uncertainties that may arise from assuming constant and uniform erodibility coefficients in simple stream power erosion models, compared to erodibilities that potentially vary spatially and temporally.
Extreme Wave Boulders at Premantura: the stamp of the storms in the northern Adriatic Sea
Authors: Vaccher Valeria , Devoto Stefano , Mantovani Matteo , Korbar Tvrtko , Macovaz Vanja , Furlani Stefano
Published: June 2022

Storms and storm surges could increase their impact on rocky coasts in the next years due to global warming. In recent years, the study of boulders moved by storm waves seems to have played an important role. A key indicator that can follow extreme storm events on rocky shores includes coastal boulders detached from the bedrock. These deposits became in focus of a several studies since play a significant role in coastal hazard assessment. First studies regarded deposits of boulder related to tsunami events, but recently many sites with large clasts related to storm waves have been discovered, also in semi-enclosed shallow basin, such as the Adriatic Sea, in the Mediterranean area.

In this study we widened the mapping of boulders recently studied at Premantura promontory (southern Istria, Croatia) in order to better assess the role of coastal morphology in boulder sedimentation. In particular, we present and discuss the role of boulder deposits in several islets close to the promontory, also considering that at the island of Sekovac boulders are definitively of artificial origin and later moved by extreme waves.

The investigation of the position, size, and mass of each boulder was created through the application of Uncrewed Aerial Vehicle Digital Photogrammetry (UAV-DP) and Structure from Motion (SfM) technique, defining the GCPS points, and providing high-resolution data.  

Boulders were identified and categorized using UAV-DP products, and their validation was done through the comparison with outputs of traditional geomorphological investigations such as field surveys including direct axis measurement and the use of Google Earth images for boulder mapping.
Can piping erosion impact environment and society? Identifying new research gaps
Authors: Bernatek-Jakiel Anita , Nadal-Romero Estela
Published: June 2022

Soil erosion is one of the hillslope processes that receives considerable attention by geomorphologists. Recently, also subsurface erosion by soil piping has become increasingly recognized. So far, the studies have been focused on the importance of soil piping in hydrological and geomorphological processes, and factors controlling piping processes. Nowadays, the Anthropocene brings the environmental changes and society depends on soil more than ever before, so the traditional studies of soil erosion processes need to be redefined. We identify new possible areas of research: (i) soil pipes and pipe collapses (PCs) as natural hazards, (ii) role of soil piping in carbon cycle, (iii) soil pipes and PCs and their relationships with biodiversity, and (iv) piping–affected areas as geodiversity sites. Natural hazards driven by soil piping are land subsidence and degradation, landslides, flooding and off-site sediment effects. Their better recognition will be a step towards better prevention and control measures in piping-affected areas. Moreover, in the context of the Global Change, soil loss due to piping may lead to carbon loss as piping dynamics is affected both by land use and land cover changes as well as climate change. Soil pipes and PCs are closely interlinked with biodiversity, both positively and negatively. On the one hand, piping erosion may directly and indirectly destroy vegetation and animals. On the other hand, in some cases it may create new habitats and provide favourable conditions for some species. Interestingly, we can see piping erosion as the contributor to the world geodiversity, which is clearly observed in badland sites. Summarizing, piping erosion may have a significant impact on environment and society, so this is a time to address and discuss new questions in erosion studies.

The research has been supported by a grant from the Priority Research Area “Anthropocene” under the Strategic Programme Excellence Initiative at the Jagiellonian University and by the Spanish MANMOUNT (PID2019-105983RB-100/AEI/10.13039/501100011033) project funded by the MICINN-FEDER.
Simplicity vs. complexity – a long-standing challenge in the simulation of landslide runout
Authors: Mergili Martin , Fischer Jan-Thomas
Published: June 2022

First approaches to analyze the propagation of hazardous, extremely rapid, landslides go back at least to the 1930s, when data-driven approaches such as angles of reach were used to estimate runout distances. Various much more sophisticated tools for the simulation of flow-type landsides including debris flows or rock avalanches, or cascading effects involving more than one type of phenomenon, have been developed since then, particularly throughout the last two decades. They build on increasingly complex physical-mathematical models, starting from comparatively simple and straightforward, depth-averaged Voellmy-type mixture models, moving to still depth-averaged two- and three-phase models able to simulate the interaction of landslides with water bodies, and currently proceeding to highly complex and highly flexible full 3D models. Phenomena such as erosion, entrainment, deposition, phase separation, or non-hydrostatic effects are increasingly well understood and incorporated into operational mass flow simulation tools.

However, this trend of increasing model complexity, supported by increasing physical process understanding and enhanced computational capacities, is not necessarily in line with the demand by natural hazard practitioners, who need capable but easy-to-handle simulation tools for their work. Besides the computational costs, it is mainly the multitude of often unknown, rather conceptual model parameters representing a barrier for practitioners towards using the more or even the most advanced approaches. Further, more complex models do not necessarily provide more accurate results than simpler ones, this always depends on the scope, purpose, and phenomenon. If only estimates of runout distances or impact areas are needed, very simple data-driven models may do the work. Even when it comes to flow thicknesses, velocities, or impact pressures, ordinary debris flows may still be better represented by comparatively simple mixture models than by parameter-hungry two- or three-phase models. Yet, more complex models are needed for more complex processes such as landslide-lake interactions or other types of process chains with dynamically changing material composition. Therefore, intelligent approaches have to be found to find an appropriate balance between simplicity and complexity.

Mainly based on seven years of experience with the depth-averaged multi-phase mass flow simulation framework r.avaflow, we will discuss the main challenges and ideas to find a useful balance between simplicity and complexity in the simulation of landslide runout.
Relationships between alluvial fans, channel steepness and drainage area in the Andean piedmont, Colombia.
Authors: Breda Caio , Nascimento Pupim Fabiano , Gomez M. Sebastian , Parra Maurício
Published: June 2022

Mountain regions and their foreland basins sustain a set of landforms (e.g., floodplains, fluvial terraces, and alluvial fans) that are sensitive to climatic and tectonic changes. The variation of these factors can change the rates of incision and aggradation in river valleys and trigger the propagation of the imbalance signal along with the river profile, transforming the local relief. Geomorphic indices (e.g., the normalized channel steepness index, ksn) highlight river profile and slope gradient changes. In order to advance the knowledge about the dynamics of the foreland regions, a central question emerged: Are larger fans more related to basins with high stream power (ksn) or to drainage area? To answer this question, we mapped alluvial fans and used Ksn indices to identify significant variations in stream power along the basins that constitute the headwaters of the Guaviare River, in the Eastern Cordillera of Andes, Colombia. The alluvial fans were mapped using visual interpretation of Landsat imagens and digital elevation models from Coopernicus DEM (30 m resolution). The ksn index and drainage area of basins upstream of the alluvial fan apex were quantified using TopoToolBox package. Results will be present in the conference. FAPESP Grant (#2020/11047-1)
Anthills and termite mounds as a biogeomorphological heritage
Authors: Bétard François
Published: June 2022

Anthills and termite mounds are prominent features in many geomorphological landscapes of temperate and tropical geosystems. They individually constitute small-scale landforms (up to 10 m high for the tallest termite mounds) and their spatial assemblage can reach very high densities (up to 2,500 mounds per hectare for the yellow meadow ant Lasius flavus), generating a rough topography of more or less regularly spaced mounds at the landscape scale, or “moundscape”. The termite mound fields of African savannas and the anthill landscapes of European grasslands are famous examples of moundscapes generated by these social insects. Such biogenic landforms play a key role in the understanding of Earth surface processes and have a strong relationship with both the biological and the cultural heritage. They are of great ecological importance because they create microhabitat heterogeneity and increase the patchiness of the environment, promoting a range of other animal and plant species which would not occur otherwise. The cultural and spiritual values attached to termite mounds are well recognized across Sub-Saharan Africa, and indigenous knowledge of the medicinal value of anthills is ancestrally recorded in Northern Europe. Moreover, the aesthetic value of moundscapes (architectural shape of cathedral-termitaria, curvaceousness and floral colonization of ant mounds), their dynamic dimension (with both abandoned and active mounds) and their imbrication into broader landforms (e.g., termite mounds over a laterite plateau, anthills over a tidal marsh) make them potential candidates to geomorphosite designation. Given their mixed composition, both mineral and organic, and their biological origin, anthills and termite mounds can be considered as elements of a biogeomorphological heritage, i.e. a hybrid form of geoheritage and biological heritage. The multitude of values and ecosystem services they provide to humans justify their conservation as well as their sustainable use for ecogeotourism and environmental education.
Late Pleistocene History of the River Valleys of the East European Plain's center
Authors: Matlakhova Ekaterina , Panin Andrei
Published: June 2022

Large meandering palaeochannels (macromeanders) are found in the river valleys of the East European Plain. Channel parameters of such macromeanders are few times larger than the recent ones of the same rivers. Such macromeanders are widespread in the temperate climate zone of the Northern Hemisphere. Formation of these macromeanders is usually associated with Late Glacial (the end of MIS 2). The main aim of our study was the reconstruction of the river valleys’ development of the Central part of the East European Plain and establishing of the absolute chronology of the large paleochannels formation in this region. Few key sites were studied in the river valleys of the Central part of the East European Plain. Hand and mechanical coring, examination of natural and human-made exposures, sampling for different types of analysis, geomorphological discriptions and topographic profiling were done during the fieldworks on the key sites. Radiocarbon and OSL dating, grain-size and spore-pollen analysis were done in the laboratories.

Data analysis shows the following results and conclusions. The alternation of high and low river runoff was typical for the valleys of the study region in the end of the Late Pleistocene. This led to the alternation of river incision and aggradation in the valleys. About 30-35(40) ka ago there was epoch of rivers incision. High runoff is proposed as the reason of this incision. Before LGM rivers had already been incised down deeper than the modern levels. LGM time (20-23 ka ago) was characterized by cryoaridic conditions, low runoff and accumulation in the river valleys. Not only alluvial, but also aeolian accumulation in the river valleys was characteristic for this period. In that time aeolian covers and aprons few meters thick were formed in river valleys (mostly on the terraces’ surfaces). After LGM the high runoff epoch started, which was dated 12-19 ka ago. In that time large meandering palaeochannels (macromeanders) and modern wide high floodplains were formed in the river valleys. These macromeanders were formed under conditions of extremely high spring discharges in severe climate conditions. Our data shows that this epoch of high runoff was interrupted by a short low runoff period (~15-16 ka ago). So, the Late Pleistocene epoch of high floods and large paleochannels formation had two periods – about 17-19 ka and 12-15 ka ago. Runoff in the Holocene became lower than in the Late Pleistocene, channel parameters decreased.
The influence of river-hillslope interactions on fluvial hazards in the Himalaya
Authors: Cook Kristen , Andermann Christoff , Puri Bijaya , Schwanghart Wolfgang , Adhikari Basanta Raj
Published: June 2022

The Himalayas experience frequent fluvial disasters due to precipitation-driven floods, as well as events such as glacial lake outburst floods and landslide lake outburst floods. Such floods represent a major hazard, causing loss of life and damage to property and infrastructure. In steep mountain landscapes, rivers and hillslopes are often tightly linked, and interactions between these domains can strongly influence flood impacts and dynamics. Floods can erode the base of hillslopes and terraces, driving mass wasting, while hillslopes can deliver large amounts of coarse sediment, driving aggradation and potentially creating temporary dams. Data from a 2016 glacial lake outburst flood in central Nepal demonstrate that flood-induced mass wasting can be a dominant driver of damage from such an event, with at least 85 homes and many stretches of the Araniko highway destroyed by slope failures. The hillslope impacts were not confined to the event itself, as a number of hillslopes experienced longer-term destabilization, continuing to slide for years following the flood and hampering efforts to rebuild the road. While the 2016 event represents a case of flood-driven hillslope hazards, a 2021 event on the Melamchi River in central Nepal demonstrates the amplification than can occur with more complex river-hillslope feedbacks. Here, the interaction between the river and a range of hillslope inputs, including a paleo landslide dam, recent colluvial deposits, and a flood-triggered landslide dam, led to massive aggradation throughout the Melamchi River. This aggradation substantially altered the river channel, amplifying the impacts of later floods and promoting additional mass wasting, further increasing the sediment loading of the river. This perturbation of the river-hillslope system is still ongoing, and is expected to cause continued hazard over the next monsoon seasons. These cases demonstrate the importance of considering hillslopes and river channels as an integrated system rather than as distinct domains during assessment of geomorphic hazards in steep mountain landscape such as the Himalaya.
Sustainable metropolis development: a challenge for urban geomorphology research
Authors: Melelli Laura , Brandolini Pierluigi , Del Monte Maurizio , Pica Alessia , Reynard Emmanuel
Published: June 2022

The scientific literature on urban geomorphology focuses on city case studies with a centuries-old historical settlement and analyze mainly the downtown areas.

In this framework, the well-known multitemporal and multidisciplinary research procedures, including ancient maps and documents, are widely available for the recognition of the original morphological arrangement and for identifying the spatial and temporal changes to the landscape due to the human presence.

This approach has inevitably centered the research on case studies which, for the most part, are on the European territory. The main European cities in fact arose many centuries ago when the choice of the site was conditioned also, and above all, by morphological and more generally geological conditions (availability of underground water resources, proximity to rivers, lakes and seas, mineral resources, etc.).

The current trend towards urbanization (it is expected that in 2030 more than 60% of the world population will live in urban areas) affects Africa and Asia in particular, with a city model greatly different from what we are used to conceiving in the "old continent". These metropolises or in some cases megalopolises, are a little known but very interesting school field to understand the differences in terms of hazard and resources for such large areas.

In the same time the European cities are growing too, with evident problems in contrast to the idea of a sustainable development. Even if the social and economic differences between European cities and the African and Asian ones are well evident, comparing these urban models for the geomorphological investigation could reveal interesting food for thought.

Our opened questions are: in a holistic model of sustainable urban development what can be the role of geomorphology for large cities? Does it make sense talking about transformations of natural morphology in areas where urbanization has reached such a high level of impact, does it represent a lesson to be learned? Above all, can research on urban geomorphology be a useful approach for a sustainable model of urbanization?

This contribution proposes a guideline for the study of urban geomorphology in these new metropolises, identifying the differences in terms of boundary conditions, related issues and the role of geomorphology as a parameter for reaching the sustainability.
Geotourism assessment at municipal scale in Costa Rica
Authors: Quesada-Valverde Michael E. , Quesada-Román Adolfo
Published: June 2022

The inventory and evaluation of geosites throughout the world have been increasing. These approaches constitute the baseline for geoconservation and geotourism projects. In Costa Rica, initiatives presenting inventories of geomorphosites in volcanic and paleoglacial environments are recent. This work aims to present an inventory and evaluation of geosites in Coto Brus municipality. This is an initiative of the Municipality of Coto Brus to develop an inventory of its natural attractions to support the creation of tourist routes within the framework of the OVOP (One Village One Product) Coto Brus project. Many of these natural attractions are geosites such as waterfalls, paleontological sites, archaeological sites, wetlands, extinct volcanoes, and paleoglacial summits which exhibit a rich geodiversity. Our methodology was based mainly on Santos et al. (2020) and Reynard et al. (2016). The geomorphological context of Coto Brus was made using GIS and existing bibliography. Moreover, we consulted local tourism web pages, tourist guides and bibliographic consultation obtaining a preliminary list of geosites. A preliminary evaluation was used for the non-inclusion of irrelevant sites in the final inventory. Sites with high values for geosciences and high rarity were included. A characterization of its geomorphological aspects, associated interests, use, and management issues was carried out in each geosite through descriptive tables. A quantitative evaluation of its potential for scientific, educational, geotourism use, and its potential for promotion was used. A thematic map was generated with the location of the geosites associated with the results of the quantitative evaluation. Finally, the results of the inventory and evaluation of geosites are articulated with the promotion of tourist routes within the framework of the OVOP Coto Brus project through recommendations and proposals for use, management, and degradation risks. It is a quick decision-making tool that will allow stakeholders to identify the main values of each geosite.
Impact of 2.7-ka climatic event on the local inhabitants of the Ararat Plain seen from the Metsamor perspective (S Armenia)
Authors: Woronko Barbara , Jakubiak Krzysztof , Iskra Mateusz
Published: June 2022

Climate variability may have played a significant role in the rise and collapse and reorganisation of many ancient civilizations. Such changes had a particularly strong impact on the political and cultural development of societies inhabited various parts of the Middle East during the first millennium BC. In this context, the South Caucasus, located on the Middle Eastern border zone, belongs to the most attractive areas for multidisciplinary research in the field of climate geology and archaeology.

Metsamor is a fortified protohistoric settlement located in the bottommost part of the Araxes valley (S Armienia). Results of geological survey coupled with interpretation of archaeological and palynological data collected at the study area, indicated great climate fluctuations which could impact the life of local community. These fluctuations were identified with 2.7 ka climatic event based on the age dating and detailed stratigraphy of sediment at the study site. According to Singha et al. (2019), the interval between ~ 2800 and 2690 yr BP is considered as one of the wettest period in the Near East over the past 4000 years. It was followed by a ~ 125-years period of aridity interval. Transition from wet to dry climate conditions is referred to as a 2.7 or 2.8 ka BP event. From the archaeological perspective, its impact on Metsamor can be found in the record of various processes related to gradual abandonment of the settlement,  and changes in the subsistence economy of its inhabitants. As a consequence, their livelihoods shifted from agriculture to cattle and goat breeding.

This work was supported by the National Science Centre Poland. Grant no. 2018/29/B/HS3/01843.
Identification and soil characteristics of coastal terraces along the northern coast of the Gulf of Mexico.
Authors: Liebens Johan , Randall Chelsea
Published: June 2022

Delineation of relict marine terraces along the Northwest Florida coast facilitated investigation of soil development within the Gulf of Mexico (GOM) coastal plain. Previous research in the region that defined coastal terraces primarily relied on topographic studies with little consensus on the number and extent of terraces. Research investigating soil development within the GOM coastal plain is also limited. Our study utilized GIS and a LiDAR-derived Digital Elevation Model (DEM) to apply a Surface Classification Model (SCM) for selection of terrace surfaces based on slope and surface roughness. Hypsographic analyses of the SCM output identified potential terrace surfaces but visual interpretation along transects across the surfaces was necessary to refine the bounding terrace elevations. Five terraces were defined. Soil properties known to exhibit time related trends were analyzed across the delineated terraces. At increasing elevations, and presumably increasing ages, soils exhibited a thickening of both the solum and Bt horizon, an increase in clay content, and a decrease in organic matter content. The lowest terrace had the greatest solum thickness due to the presence of thick Histic epipedons and thick Spodic horizons. Bt horizons were observed at increasingly greater depths, with the exception of the highest terrace, where it was at a shallower depth. This is likely due to advanced erosion associated with the older age of the terrace and the higher elevation and greater exposure of the surface. This study demonstrates that GIS and LiDAR-derived DEMs are valuable tools to systematically and semi-automatically map marine terraces on a regional scale.
Machine learning applied to soil erosion analysis in sub-watersheds with burned areas
Authors: Folharini Saulo , Marques Tiago , Silva Sara , Novais Jorge , Bento-Gonçalves António , Vieira António
Published: June 2022

Soil erosion increases after forest fires contributing to the mobilization, transport, and deposition of sediments and nutrients in watersheds. This scenario interferes with water quality. Faced with a climate change scenario, forest fires in the Mediterranean region tend to increase, consequently, soil erosion must increase together, aggravating water availability. Measures to minimize the effects of soil erosion in watersheds must be used to guarantee the water security of the population and protected areas play an important role in this context. This study analyzed 761 sub-watersheds in northern Portugal, to evaluate machine learning models in watersheds with recurrent fires. The analyzed area has a high recurrence of forest fires and where important districts of the country such as Porto and Braga with high population density are located, in addition to protected areas where springs of watercourses that integrate important watersheds such as Douro, Cávado, Ave, and Mondego. The parameters analyzed were: total burned area of ​​the sub-watershed in the period 1975-2020 (variable target), soil erosion by water in Europe - Revised Universal Soil Loss Equation (RUSLE2015), Topographic Wetness Index (TWI), and the morphometric parameters: Area (A), Perimeter (P), Length (L), Width (W), Orientation (O), Elongation ratio (Re), Circularity ratio (Rc), Compactness coefficient (Cc), Form factor (Ff), Shape factor ( Sf), Altitude, Slope, Curvature. These data was analyzed with the machine learning Generalized Linear Models (GLM), Support Vector Machine Linear (SVMLinear), Support Vector Machine Polynomial (SVMPoly) and Random Forest (RF). The analysis was developed in R language using the classification and regression training caret package. The average R2 for each model was RF (0.97), SVMpoly (0.96), SVMLinear (0.78) and GLM (0.78). In an analysis of boxplot plots of R2, Root Mean Square Error (RMSE) and Mean Absolute Error (MAE) the RF and SVMpoly models recorded lower dispersion of R2 and lower values ​​of MAE and RMSE. While the GLM and SVMlinear models showed greater data dispersion in the three accuracy measures of the models. Regarding the analyzed parameters, those that registered the greatest importance were A, Cc, P, Rc, W, RUSLE2015, and TWI, indicating that an analysis that considers morphometric parameters, together with soil erosion data by water and soil moisture is an important indicator in the analysis of soil erosion in watersheds. The study was developed within the scope of the CLICTOUR project (Project NORTE-01-0145-FEDER-000079), supporting fund European Regional Development Fund.

Keywords: Soil erosion, sub-watersheds, machine learning, burned areas, water security.
Graph theory structure to describe sediment connectivity: application in the Beaujolais vineyard landscapes
Authors: Pic Jessaica , Fressard Mathieu , Cossart Etienne
Published: June 2022

The landscape structure elements in agricultural catchments (ditches, hedges, pounds etc.) are known to have a major role in hydro-sedimentary transfers. They determine sediments availability, sediment pathways, water and sediments (de)coupling and connectivity patterns from source to sinks. However, linear drainage infrastructures remain often poorly represented in hydro-sedimentary modelling despite their major influence on flows redirection and concentration. Therefore, understanding the link between the catchment landscape structure and the transfer processes at its outlet is still a major challenge. Graph theory has been proved to be a significant tool to investigate sediment connectivity among agricultural catchments as it allows an explicit representation of linear and punctual elements of the landscape.

Based on a detailed inventory of linear landscape elements and a continuous monitoring of sediment fluxes, we built a new graph theory framework to comprehend sediments transfers in a dense agricultural drainage network in the Beaujolais vineyard (France). It integrates all types of linear infrastructures that might canalize water and sediment fluxes (tracks, ditches and soil bunds) and sediment traps used by winegrowers. From the intersection of the drainage network and a topographic graph, we went for spatial analysis and applied the index of connectivity (IC), to extract effects of (dis)connectivity and to compare several spatial configurations (i.e. topographic graph excluding linear infrastructures). To small catchments (8km²) of the Beaujolais vineyard are compared the effect of different landscape structures on sediment connectivity. Drainage network outlets were extracted to distinguish direct connections to the river in comparison to sediment sinks. The network structure emphasizes a reduction of sediment connectivity on the upper slope unlike on the lower slope where it is increased. Describing sediment structural connectivity through landscape structure analysis allows to identify the drainage infrastructures efficiency and might be of interest in a management perspective.
Exploring the multi-faceted potential of luminescence profiling via the portable reader in various fluvial depositional systems (NE France)
Authors: Rixhon Gilles , Bégorre Céline , Euzen Cassandra , Fuchs Coraline , Jautzy Timothée , Laible Jessica , Schmitt Laurent
Published: June 2022

Along with the development of “classical” optically stimulated luminescence (OSL) dating, portable luminescence readers have been increasingly employed in a wide breadth of geomorphological settings over the last decade. Portable measurements of bulk samples along depth profiles yield infra-red and optically stimulated luminescence net intensities (IRSL/OSL). The signal build-up depends on (i) the burial duration of the sediment, (ii) the dose rate, (iii) the inherited dose at time of burial, (iv) the mineral composition and (v) the luminescence sensitivity of the minerals. In fluvial landscapes, however, the handful of existing case studies mostly focused on the sole identification of alluvium’s unconformities via luminescence profiling. We argue here that this approach shall go beyond the mere one- (or sometimes two-) dimensional sedimentary screening and steer towards the production of three-dimensional chronostratigraphical information.

This study presents the outcomes of a luminescence-profiling approach performed in a wide array of fluvial depositional systems located in the Upper Rhine Graben and the adjacent Vosges Mountains (NE France). They include:

modern and historical overbank fines from the main stem (Rhine) and its tributaries (Bruche and Sauer Rivers);

palaeomeanders and swale-and-ridge topography (Bruche);

Holocene terrace deposits (Bruche);

fluvio-glacial deposits (probably) from the Last Glacial Maximum (Cleurie Valley).

We thus explore the ability of the reader to measure signals of varying intensities in different morpho-sedimentary units of clearly distinct ages. The results globally show:

a consistent pattern of downward increasing OSL/IRSL signal intensities, although some sharp contrasts (i.e., shifts of one order of magnitude in signal intensities) in some sequences could be identified (e.g., Rhine);

a larger scatter of OSL/IRSL signal intensities in the sandy fraction than in the silty fraction, probably reflecting the influence of grain size on the signal accumulation (requiring further investigation);

the potential of the portable reader as a rapid and efficient tool for tracing historical overbank fine deposition in floodplains.