Geomorphological Processes Research Articles

A variable increase of debris cover on Pyrenean glaciers from 2000 to 2022

AbstractThe last remaining very small glaciers (< 0.5 km2) of the Pyrenees are the southernmost glaciers in Europe and respond rapidly to climate variability. Most of them are also influenced by local topographic factors and geomorphological processes impacting the energy and mass balance. This paper presents the first temporal study on the changes in debris cover on Pyrenean glaciers from 2000 to 2022 at a regional scale. The data allowed for the first analysis of the lithological characteristics of each glaciarised cirque in order to identify possible factors that determine the evolution of debris input. We manually mapped the extent of supraglacial debris with corresponding glacier outlines using very high-resolution aerial imagery and the existing glacier inventories from 2000, 2011, 2020 and 2022. The results show that debris cover on Pyrenean glaciers has increased significantly in number and extent over the study period whilst glaciers continue to decline and shrink. In 2022, 14 of the 18 remaining glaciers have debris cover greater than 10% of their area, and six have debris cover greater than 40%. The observed increase in debris cover is much stronger for glaciers determined by topoclimatic factors and located on metamorphic and sedimentary cirques, which underlines the important role of paraglacial processes in their development. Meanwhile, glaciers on granitic cirques have lower debris cover and have shown a lesser increase compared to initial measurements conditions. Future work should focus on understanding debris sources and their characteristics to determine the role of debris cover in the response of Pyrenean glaciers to climate change.

Trapnell's Upper Valley soils of Zambia: the production of an integrated understanding of geomorphology, pedology, ecology, and land use

Abstract. The Ecological Survey of Northern Rhodesia (now Zambia), undertaken in the 1930s under the leadership of Colin G. Trapnell, was a seminal exercise to relate soil, vegetation, and agricultural practices through intensive field observation. In this article, we examine early activities of the survey in the Upper Valley region around the Kafue Flats and the neighbouring plateau, where Trapnell recognized how geomorphological processes of normal erosion gave rise to distinctive soils with associated vegetation communities and considerable potential for crop production. We consider how Trapnell's approach to fieldwork gave him a particular insight into how soil conditions constrained agriculture in the Zambian environment; the adaptive value of traditional practices; and how these were developed as communities moved and responded to social, economic, and environmental change. We argue that Trapnell's work was innovative and that distinctions must be drawn between his understanding and what has been called the ecological theory of development. Close attention to Trapnell's experience could inform modern efforts to understand indigenous knowledge of African soils and their agricultural potential.

Geospatial Modeling of Aeolian Dynamics in the Algerian Steppe from Zahrez Chergui to Hodna

Assessing the hazards associated with aeolian geomorphological processes requires a fundamental understanding of their spatial distribution. These phenomena often have detrimental impacts on the environment, economy, and society. This problem is prevalent in the Algerian steppe, encompassing the Zahrez, Chergui, and Hodna regions. This study proposes a research method for developing more accurate and simpler indices to evaluate the extent and directionality of sand migration. Specifically, it examines surface characteristics, such as altitude, slope, and slope exposure. However, some tools used for spatial modeling of wind dynamics necessitate corrections to account for the effects of topography and surface features on wind, which for this study are implemented using spatial techniques. The results are incorporated into the model developed by Fryberger, which requires wind data and a Digital Surface Model (DSM) to estimate the factors included in this model. The findings indicate that the average potential quantity of sand movement is 64 t m-1 yr-1 over the entire study area, with 37.3% of the region experiencing severe deflation of 140 t m-1 yr-1. This result can be utilized to enhance the understanding of the direction and magnitude of sand movement in any region.

The Impact of Population Density, Land Cover, and Spatial Patterns on the Geoecological Evaluation of the Surabaya Coast

Abstract Coastal areas are vulnerable to the influence of geomorphological processes from activities in the waters, so that the condition of coastal ecosystems will always change according to the dynamics that occur on the coast, both changes could be occurred in coastlines and land cover. Geoecology is the spatial interaction between natural phenomena and their relationship to phenomena in a particular ecosystem. Surabaya is a coastal city that frequently experiences changes in land cover. The construction of new settlements and changes in land use have a significant impact on the coastal environment of Surabaya. This research aims to determine the influence of population density, land cover and spatial plan on the geoecological evaluation of Surabaya’s coast using remote sensing data. The data used in the research is Landsat satellite image data from 1994, 2003 and 2018 (maximum likelihood classification method). The dynamics of changes in coastlines on the coast of Surabaya are caused by three phenomena, namely erosion, accretion and anthropogenic. Each phenomenon has a different value for land cover class, population density and spatial patterns. The research results show that geoecological evaluation is closely related to phenomena that occur on the Surabaya coast (value range 1-3). The geoecological evaluation value due to the erosion phenomenon is low (30%) and medium (70%). The geoecological evaluation value due to the accretion phenomenon is low (100%). Meanwhile, the geoecological evaluation value due to anthropogenic phenomena is low (25%) and medium (75%). Geoecological evaluation of Surabaya’s coast shows that it is in a “safe” condition, but there is requirement for coastline management. Where the coastal area planning process is carried out by identifying the dynamics of coastal areas and potential risks and consequences related to decisions that produce different future scenarios.

A novel comprehensive approach to soil and water conservation: integrating morphometric analysis, WSA, PCA, and CoDA-PCA in the Naama sub-basins case study, Southwest of Algeria.

This research paper presents a detailed investigation into the morphometric characteristics of sub-basins within the Naama region of Algeria, aiming to prioritize areas vulnerable to soil erosion and runoff risks. Focusing on five key sub-basins that collectively represent 75% of the Wilaya of Naama, the study employs a comprehensive methodological framework, integrating morphometric analysis (MA), weighted sum analysis (WSA), principal component analysis (PCA), and the novel approach of compositional data analysis (CoDA). Through the rigorous evaluation of sixteen distinct morphometric parameters selected based on their relevance to hydrological and geomorphological processes that influence erosion and runoff, this research provides a nuanced understanding of the factors influencing erosion susceptibility within each sub-basin. The analysis reveals a clear hierarchy of sub-basins based on their calculated compound parameters, effectively classifying them into high, moderate, and low priority categories for targeted intervention and resource allocation. The results highlight the Ain Sefra and Wadi Er Rosafa sub-basins as the highest priority areas, collectively encompassing 31.51% of the wilaya and posing the most significant threats of runoff and soil erosion. This identification allows for the prioritization of conservation efforts and the implementation of tailored management strategies in these critical areas. Furthermore, the integration of multiple prioritization approaches, including the innovative application of CoDA, ensures a robust and comprehensive assessment of the sub-basin landscapes. This multi-faceted approach provides a more nuanced understanding of the complex interplay between various morphometric parameters and their influence on erosion and runoff potential. The findings of this research have significant implications for sustainable land and water resource management within the Naama region. By identifying and prioritizing vulnerable sub-basins, the study provides a crucial foundation for informed decision-making, enabling stakeholders to implement targeted interventions and mitigate the detrimental impacts of soil erosion and excessive runoff. Moreover, the methodological framework presented in this research paper offers a valuable blueprint for similar studies in other regions facing comparable challenges. The cost-effective and time-efficient nature of the approach makes it a practical tool for prioritizing erosion and runoff risks in arid and semi-arid environments worldwide, contributing to the broader goals of environmental sustainability and land degradation neutrality.

Morphometric analysis and environmental planning: an educational approach in science and mathematics for understanding geomorphological processes in the Água das Araras watershed, Cornélio Procópio and Santa Mariana, Paraná, Brazil

The article develops a detailed morphometric analysis of the Água das Araras Stream Watershed, located in the regions of Cornélio Procópio and Santa Mariana, Paraná. The investigation focuses on the geomorphological characterization and the dynamics of processes shaping the basin's relief and drainage network. Using quantitative methods such as areal, linear, hypsometric, and fluvial planning analysis, the research aims to clarify the structural factors and environmental conditions shaping the basin.The study seeks not only to identify the natural potential and aspects of environmental vulnerability but also to suggest management actions that enable more effective and sustainable territorial planning. This work presents an important resource for future disciplines in favor of water resource preservation, besides strengthening interdisciplinary understanding of geomorphological processes and their relevance for sustainable development. Additionally, it highlights the application of these concepts in environmental education, especially in the teaching of Geography, Science, and Mathematics. Moreover, morphometric analysis proves to be a powerful tool for interdisciplinary teaching in Geography, Sciences, and Mathematics, promoting a practical understanding of natural processes and their impacts. The study concludes by emphasizing the relevance of the basin for environmental education and the necessity of conservation policies to ensure the sustainability of local water resources. The study also highlights the need for preservation policies and the importance of the watershed as an educational resource to foster environmental awareness.

Low average shoreline change rate in 51 years on the raised Aldabra Atoll

Atolls are at risk of losing their ability to physically adapt due to rising sea levels and coral reefs’ reduced sediment supply, resulting in faster erosion of reef islands. This research examines Aldabra, a raised atoll and UNESCO World Heritage Site in the Indian Ocean with diverse coastal ecosystems, to track shoreline changes against a regional sea level rise of 2–3 mm yr−1. Aerial and satellite images in 1960 and 2011 were used to study 85% of the atoll’s shoreline through a Digital Shoreline Analysis System. Over 51 years, 61% of the shoreline remained unchanged, while 24% changed at an average rate of 0.25 ± 0.36 m yr−1, a low rate compared to global atoll changes. Among the areas that did change, rates of accretion and erosion in absolute values were nearly balanced and affected similar percentages (12%) of the shoreline. However, localized changes were pronounced: for example, part of the lagoon shoreline transformed from a sandy beach to a mangrove habitat, accreting by 214 m over the period. Erosion occurred at crucial turtle nesting sites and the research station. The lagoon shoreline underwent more rapid changes than the erosion-resistant ocean shoreline, particularly in areas exposed to wind and waves. Despite its dynamic shoreline, Aldabra maintained its net shoreline and likely total land area over the past 51 years, akin to other Indo-Pacific atolls—underscoring its adaptive capacity. Our research suggests that current knowledge of geomorphological processes of low reef islands is transferable to the raised Aldabra Atoll, reconfirming similar mechanisms of island-building processes at the island crest. These insights highlight an urgent need to minimize local impacts on sediment availability and transfer that might alter the natural dynamics of the shoreline of reef islands and hence limit adaptation potential. Ongoing shoreline monitoring will remain crucial for informing timely adaptation strategies for the conservation of Aldabra’s unique ecosystem.

Designing-in WebGIS Tools for digital learning terrains in Natural Environments

Authentic learning environments (Herrington et al., 2014) have been widely acknowledged in creating engaging, meaningful and deep learning experiences, including for “novice” first-year undergraduate students (Roach et al., 2018). Natural Environments (ENVS10001) is a first-year undergraduate subject (unit) that aims to deliver foundational understanding of earth systems and processes to support studies in agriculture, natural resource management and civil engineering. One main obstacle to facilitating understanding in this domain is the unfamiliar scales of the landscape processes and phenomena (Resnick et al., 2017). Natural Environments has been using the granitic geology dominated landscape of Glenrowan in northeastern Victoria (Australia) as an authentic case study. In this presentation we explain how and why we re-designed authentic learning aligned tutorial interactions by integrating student-driven navigation of WebGIS tools such as Geoscience Australia and NatureKit portal to: (a) enable students to build understanding of how geology, geomorphology and ecology interact to result in the dynamic landscapes in the environment; (b) equip students with fundamental and valuable knowledge and skills in accessing free and publicly available datasets useful in their academic and future professional work; (c) demonstrate the authenticity of the curricular content to establish higher levels of learner engagement. The current learning design where dynamic control and interaction with spatial data is central, is just one iteration in the series of previous designs that moved from non-digital to static-digital resources in the learning environment. Generally, an anchored instruction aligned approach (The Cognition and Technology Group at Vanderbilt, 1990) was adopted. Prior to the tutorial, students attended two one-hour lectures explaining the structure of the earth, plate tectonics, and global-scale structural (volcanic and tectonic) landforms. We wanted students to develop an understanding of how, over “unfamiliar” geological (time) and spatial scales, geomorphological processes operating across different rock types resulting from geological processes (e.g. granite pluton emplacement amongst sedimentary rocks) result in the landscapes observed presently. During the class, with tutors as guides, students worked in groups and learnt how to use the Geoscience Australia portal to explore the Glenrowan region, centered around the Warby Ranges and the surrounding plains. Professional instructional videos developed in collaboration with the University of Melbourne Learning Environments media team were used to demonstrate how to use the portal to find geological and geomorphological information. Students were guided in the use of Google Earth to visualise terrain in pseudo-3D and using elevation transects. The spatial correlation of landform patterns and elements with different surface and subsurface geologies was key to unlocking students’ abilities to explain the “why” and “how” of landscape evolution, albeit at the basic level. Students had mostly positive experiences and learning outcomes shown in the post-subject survey (n = 30; scores of 4.6 to 6.0 for 12 questions on 7-point Likert scale) and comments. Technical issues encountered due to simultaneous class access to the portal, and gaps in explaining specific functionalities and their potential for further understanding, were highlighted. The authors acknowledge the strong support for this work through the University of Melbourne’s FlexAP programme.

Landscape Histories and the Search for Early Settlements along Louisiana's Bayous

Abstract Historical changes from shifting land use, the natural meandering of waterways, and the aftereffects of erosion complicate modern environments and obfuscate precontact landscapes. Although archaeologists can create stratified sampling models or employ systematic surveys, traditional field methodologies are often not suitable for site discovery, thereby limiting knowledge of ancient cultural landscapes. Many water systems in southern Louisiana, and in many parts of the world, have been covered or concealed in backswamps by natural geomorphological processes, development, or environmental degradation. Investigation standards that do not account for these changes will not be effective at identifying archaeological sites in such transformed landscapes. Discoveries made during ongoing archaeological research in Iberville Parish, Louisiana, provide examples of what can be missed and offer solutions through changes in archaeological field methods. This article advocates for a mixed-methodology approach, drawing from historical research and shallow geophysics to look at landforms and landscape changes. Strictly following state survey guidelines can muddle the archaeological record, particularly in places subject to significant landscape change from historical land-use alteration. By applying these approaches, we offer a way to reconstruct ancient landscapes and landforms that are culturally significant but often missed given the nature of modern environmental conditions.

Monitoring Coastal Evolution and Geomorphological Processes Using Time-Series Remote Sensing and Geospatial Analysis: Application Between Cape Serrat and Kef Abbed, Northern Tunisia

The monitoring of coastal evolution (coastline and associated geomorphological features) caused by episodic and persistent processes associated with climatic and anthropic activities is required for coastal management decisions. The availability of open access, remotely sensed data with increasing spatial, temporal, and spectral resolutions, is promising in this context. The coastline of Northern Tunisia is currently showing geomorphic process, such as increasing erosion associated with lateral sedimentation. This study aims to investigate the potential of time-series optical data, namely Landsat (from 1985–2019) and Google Earth® satellite imagery (from 2007 to 2023), to analyze shoreline changes and morphosedimentary and geomorphological processes between Cape Serrat and Kef Abbed, Northern Tunisia. The Digital Shoreline Analysis System (DSAS) was used to quantify the multitemporal rates of shoreline using two metrics: the net shoreline movement (NSM) and the end-point rate (EPR). Erosion was observed around the tombolo and near river mouths, exacerbated by the presence of surrounding dams, where the NSM is up to −8.31 m/year. Despite a total NSM of −15 m, seasonal dynamics revealed a maximum erosion in winter (71% negative NSM) and accretion in spring (57% positive NSM). The effects of currents, winds, and dams on dune dynamics were studied using historical images of Google Earth®. In the period from 1994 to 2023, the area is marked by dune face retreat and removal in more than 40% of the site, showing the increasing erosion. At finer spatial resolution and according to the synergy of field observations and photointerpretation, four key geomorphic processes shaping the coastline were identified: wave/tide action, wind transport, pedogenesis, and deposition. Given the frequent changes in coastal areas, this method facilitates the maintenance and updating of coastline databases, which are essential for analyzing the impacts of the sea level rise in the southern Mediterranean region. Furthermore, the developed approach could be implemented with a range of forecast scenarios to simulate the impacts of a higher future sea-level enhanced climate change.

Enormous headward and gully erosion in a floodplain area reclaimed for open-cast lignite mining during the July 2021 flood in the Inde River valley (Western Germany)

BackgroundThe July flood 2021 at the mountain front of the Eifel-Ardennes Mountains and their foreland resulted in the flooding of the lignite mining area of Inden in Germany. The mining activities resulted in large-scale anthropogenic changes to the relief and fluvial system, leading to a landscape that is no longer adjusted to the recent process-response system. This paper concentrates on the Inde River, where lignite mining led to the relocation of a 5-km-long river section. The flood event resulted in the temporary avulsion of the Inde River into the former channel and, ultimately, in the flooding of the open-cast lignite mine Inden.ResultsThe flooding of the open-cast lignite mine Inden led to headwall erosion and enormous sediment mobilisation, mobilising more than half a million cubic metres of sediment within a few hours, forming a 700-m-long deeply incised channel cut. Thereby, the underlying bedrock, near-subsurface man-made structures, and former river channels influence the erosional processes to different degrees. Surface erosion is likely to be the decisive process, and subsurface erosion is likely to play a secondary role. In both cases, former channels and mill ditches were likely impacting the course of erosional processes.ConclusionsDuring high flood events open-cast mining sites in floodplains are endangered by enormous erosion and sediment transport within a short period of time (several hours). Understanding such complex erosion and depositional processes in open-cast mining areas could provide a blueprint for geomorphological processes and hazards in these anthropogenically shaped fluvial landscapes. Further, information on historic impact in the area is crucial to estimate potential risks.

What do trees reveal about the sliding of the lateral moraine of the Belvedere Glacier (western Italian Alps)?

The debris-covered Belvedere Glacier is an iconic place for investigating glacier dynamics and geomorphological processes typical of high mountain environments. Moreover, being located in an area highly suited to tourism, glacial and geomorphological hazards can evolve into risk scenarios. Particular attention has been paid during this research to the surge-type event that occurred at the beginning of the 21st century, and to the recent sliding of a lateral moraine nearby the chairlift station. Tree sampling was performed (19 trees on the lateral moraine; 10 undisturbed trees), and the results were compared with morphometric measurements on orthophotos of different years. Besides sampling trunks, the six available exposed roots (13 samples) from a tree located along the sliding niche were sampled to identify the exposure time. Morphometric measurements of the touristic trail dislocation indicate a sliding rate of 1.87 m/y – 1.98 m/y (2018–2023), while the regression rate of the sliding niche is 1.70 m/y (2021–2023). The age of trees along the trench is variable (14–49 years), as is the signal of compression wood, enhancing differentially the passage of the surge wave and the subsequent glacier downwasting. The beginning of root exposure occurred between 2017 and 2019, before the effective evidence of large fractures in the ground. Moreover, the roots show traumatic resin ducts in the period between 2020 and 2022, confirming the tree disturbance. In conclusion, the investigated events are recorded differentially in the sampled trees, especially in roots, anticipating the actual commencement of ground failure. A multidisciplinary approach, including remote sensing, field survey, and dendrogeomorphological analysis is essential to define the dynamics of complex systems.

Geomorphological processes and landforms in the Alpine Sulzenau Valley (Tyrol, Austria): Glacier retreat, glacial lake evolution and the 2017 glacial lake outburst flood

Geomorphological processes and landforms in the Alpine Sulzenau Valley (Tyrol, Austria): Glacier retreat, glacial lake evolution and the 2017 glacial lake outburst flood

Embodying Place: Charting the Badlands

I draw to recall the sensations of moving and resting within the landscape, images of place as translated through body, material and mark. In Charting the Badlands, gesture-driven mixed-media drawings fuse a lived, sensory experience of the natural geological environments of the American Southwest with the act of inventional mapping. While walking within the canyons, badlands and arroyos of the high desert, I gather clay, silt and soils to process into pigments in the studio. These pigments combine with my body’s gestured marks to map a memory of moving through place, a fragment of lived geological time. Drawing actions may echo geological processes of deposition, sedimentation and erosion. While not literal representations of place, the drawings reference geomorphological processes and evoke the surface of the earth as seen at altitude, with the viewer moving within and over the terrain. By physically walking the land, gathering soil and drawing with handcrafted pigments, I bridge the raw elements of the landscape with a gestural cartographic sense. This act of drawing is one of remembering the sensations unique to the experience of the flesh body within the lithic landscape, translating sense into a marked language of geological form. By using the soils gathered from the terrain as a self-referential drawing medium, the drawings invite a movement in both temporal and physical scale, a consideration of the history and context of the land embedded within the image, as well as the ground upon which one physically stands.

ОЦЕНКА И КАРТОГРАФИРОВАНИЕ СТЕПЕНИ ОПАСНОСТИ ГЕОЛОГО-ГЕОМОРФОЛОГИЧЕСКИХ ПРОЦЕССОВ ЧАРЫНСКОГО ГОСУДАРСТВЕННОГО НАЦИОНАЛЬНОГО ПРИРОДНОГО ПАРКА

The purpose of this article is to assess and compile an integrated map of the hazard degree of geological and geomorphological processes in the Charyn State National Nature Park (SNNP) to ensure visitor safety and protect tourist infrastructure. The study used field methods to determine hazardous geological and geomorphological processes. Based on the collected data, a comparative analysis was performed in office conditions, and a cartographic method was applied using GIS technologies to create thematic maps. The hazard assessment was carried out based on vertical and horizontal dissection, slope steepness and exposure, lithological composition of rocks and functional zones. As a result of the study, a map of the hazard degree of geological and geomorphological processes for the territory of the Charyn SNNP was compiled. Hazardous landslide-talus and erosion processes (lateral and gully erosion) were identified, posing a threat to tourists and hindering the safe development of the SNNP activities.

Influence of Marine Currents, Waves, and Shipping Traffic on Sulina Channel Fairway at the Mouth of the Black Sea

This study comprehensively explores the intricate hydrodynamic and geomorphological processes that affect the Sulina Channel and bar area. It employs advanced hydrodynamic, wave, and sediment transport models to simulate the influence of marine currents, waves, and shipping traffic on sediment transport and deposition patterns, providing valuable insights for maintaining navigable conditions in the Sulina Channel. It is shown that sediment deposition is highly dynamic, particularly in the Sulina bar area, where rapid sediment recolonization occurs within one to two months after dredging. The simulation indicates that vessels with drafts of 11.5 m cause notable erosion. In comparison, drafts of 7 m have a minimal impact on sediment transport, emphasizing the importance of managing vessel drafts to mitigate sediment disturbances. This research highlights and quantifies the siltation phenomenon from the Black Sea to the mouth of the Sulina Channel, effectively addressing the challenges posed by natural and anthropogenic factors to ensure the Channel’s sustainability and operational efficiency.

Multitemporal Quantification of the Geomorphodynamics on a Slope within the Cratère Dolomieu at the Piton de la Fournaise (La Réunion, Indian Ocean) Using Terrestrial LiDAR Data, Terrestrial Photographs, and Webcam Data

In this study, the geomorphological evolution of an inner flank of the Cratère Dolomieu at Piton de La Fournaise/La Réunion was investigated with the help of terrestrial laser scanning (TLS) data, terrestrial photogrammetric images, and historical webcam photographs. While TLS data and the terrestrial images were recorded during three field surveys, the study was also able to use historical webcam images that were installed for the monitoring of the volcanic activity inside the crater. Although the webcams were originally intended to be used only for visual monitoring of the area, at certain times they captured image pairs that could be analyzed using structure from motion (SfM) and subsequently processed to create digital terrain models (DTMs). With the help of all the data, the geomorphological evolution of selected areas of the crater was investigated in high temporal and spatial resolution. Surface changes were detected and quantified on scree slopes in the upper area of the crater as well as on scree slopes at the transition from the slope to the crater floor. In addition to their quantification, these changes could be assigned to individual geomorphological processes over time. The webcam photographs were a very important additional source of information here, as they allowed the observation period to be extended further into the past. Besides this, the webcam images made it possible to determine the exact dates at which geomorphological processes were active.

LANDSCAPE CHANGES BASED ON HYDROLOGICAL CHARACTERISTICS IN THE WAE RIUAPA WATERSHED WEST SERAM REGENCY, MALUKU, INDONESIA

Changes in the Wae Riuapa River Basin landscape in West Seram Regency, Maluku, reflect complex ecological and social dynamics. The Wae Riuapa watershed is an integral part of the hydrological cycle in the region, influencing water availability, water quality, and geomorphological processes. This research aims to model changes in the landscape of the Wae Riuappa watershed regarding hydrological characteristics. The research method uses ArcGIS 10.3 for spatial analysis of 2010 and 2020 Landsat images and hydrooffice 12.0 software, BFLOW 3.0 module, a hydrological model for graphical separation of daily discharge. The results of modeling landscape changes in the Wae Riuappa watershed on hydrological characteristics obtained a regression model that depicts landscape changes as having a significant simultaneous and partial influence on discharge conditions in the Wae Riuappa watershed during the research period. The spatial pattern of area distribution for the nine land cover types in the study period was relatively similar. Widespread forest land cover still dominates the landscape of the Wae Riuapa watershed. However, the pattern of widespread distribution of changes is starting to decrease in primary and secondary forest land cover. Meanwhile, the distribution pattern of changes in agricultural land and mixed gardens and settlements has increased slowly and significantly. The results of a multi-temporal analysis of the hydrological characteristics of the Wae Riuapa watershed show that the daily discharge trend experiences multi-temporal fluctuations.

Fifty years marshland changes in a large floodplain lake: Natural driving or human impact?

Study region: Poyang Lake, the largest freshwater floodplain lake in China. Study focus: Marshlands in a floodplain, as the typical natural wetland offering vital habitats for various organisms, are sensitive to environmental changes. The spatiotemporal changes of marshlands were investigated and their driving forces from both natural factors and human activities were discussed. The remote sensing image data from 1973 to 2022 was adopted to explore the long-term changes of marshlands exposed in dry season. New hydrological insights for the region: Over the past fifty years, the total area of marshlands in Poyang Lake is around 2540–2718 km2 and has undergone substantial changes. It follows the bell-shaped curve pattern with continuous rise since 1970s and reach the maximum at the end of 20 century and then fluctuating decline. Different evolutionary patterns were identified in different lake regions owing to the combination of human activities and natural processes. The expanding marshlands mainly concentrate in the central lake, while the significant losses of marshlands are observed in the northern lake（By sand mining and dyke constructions）. In the southern lake, sediment input from inflow rivers deposited naturally in the river mouth elevated the lake bed and lead to delta expansion（A 3.1 km expansion has been observed）. The complex geomorphological processes and fishery activities also create the dish-shaped internal sub-lakes in marshlands.

Soil Genesis of Alluvial Parent Material in the Qinghai Lake Basin (NE Qinghai–Tibet Plateau) Revealed Using Optically Stimulated Luminescence Dating

Alluvial parent material soil is an important soil type found on the Qinghai–Tibet Plateau (QTP) in China. However, due to the limited age data for alluvial soils, the relationship between alluvial geomorphological processes and soil pedogenic processes remains unclear. In this study, three representative alluvial parent material profiles on the Buha River alluvial plain in the Qinghai Lake Basin, northeast QTP, were analyzed using the optical luminescence (OSL) dating method. Combined with physical and chemical analyses of the soil, we further analyzed the pedogenic process of alluvial soil. The alluvial parent material of the Buha alluvial plain predominately yielded ages between 11.9 and 9.1 ka, indicating that the alluvial soil began to form during the early Holocene. The development of the alluvial soil on the first-order terrace presents characteristics of entisol with multiple burial episodes, mainly between 8.5 and 4.0 ka, responding to the warm and humid middle Holocene and high lake levels.