Bedload transport occurs when a sufficiently strong flow of fluid shears a bed of loose sedimentary grains of millimeter or larger size. Here, we show that a recently proposed artificial numerical method to alter fluid-particle interactions in grain-resolved numerical bedload simulations is physically unrealistic. We conclude, supported by independent modeling, that data created using this method, unlike previously claimed, does not resolve the issue of grain shape effects on bedload transport.

The Mortuary Temple of Hatshepsut is one of Egypt's key heritage sites but is potentially threatened by rockfalls from a 100 m high limestone cliff. We transferred established monitoring techniques from alpine environments to this UNESCO World Heritage Site and evaluated their performance in a historically sensitive desert environment. Our study presents the first evidence-based event and impact analysis of rockfalls at the Temple of Hatshepsut, providing vital data for future risk assessment.

Our study examines erosion in a small, pre-Alpine basin by using cosmogenic nuclides in river sediments. Based on a dense measuring network we were able to distinguish two main zones: an upper zone with slow erosion of surface material, and a steeper, lower zone where faster erosion is driven by landslides. The data suggests that sediment has been constantly produced over thousands of years, indicating a stable, long-term balance between contrasting erosion processes.

Many alcoves on Mars resemble glacial cirques on Earth. While some contain glacier-like forms, many do not, and they have never been studied at a large scale. We mapped ~2,000 alcoves in Deuteronilus Mensae and identified 435 as "cirque-like."  These show geomorphic signs of past glaciation and mainly face south–southeast, implying ice accumulation during high obliquity. Further research is needed to confirm the style of glaciation as either warm-based or cold-based. 

Characterizing the grain size of river sediments is necessary for estimating sediment transport rates in rivers. In order to understand sediment transport at large spatial scales, grain size information across river basins is needed, but methods for accomplishing this are limited. Here, I introduce a new method for using measurements of grain size in discrete locations to estimate full grain size distributions across entire watersheds.

This paper shows how glacier-related sediment supply changes in response to earthquakes and climate warming at a catchment in the eastern Himalayas using several decades of aerial imagery and high-resolution UAV data. The results highlight the importance of debris-flow-driven extreme sediment delivery on landscape change in High Mountain Asia that have undergone substantial climate warming. This study is helpful for a better understanding of future risk of periglacial debris flows.

We usually simulate how landscapes evolve by starting from an imaginary situation in the past, and applying physical laws to simulate the effect of erosion and tectonics. Here, we reverse the approach: starting from today's landscape, we work backwards to find out how it has evolved. Using a simple physical description of erosive and tectonic processes, we can infer which areas are more sensitive to erosion, or how the landscape looked like before erosion, or how fast it has been uplifting.

In natural rivers, flow variability and sediment heterogeneity affect how sediment grains are transported. A unique law that predicts the total amount of sediment transportable by a river for a wide range of sediment mixtures and flow conditions exists, but unclear trends remain. Two improvements to this law – a standardized onset of sediment transport and a common reference transport height across all sizes – appear to be critical to having a functional multi-grain-size total sediment load.

We use computer models to study how landscapes respond to changes in rainfall and tectonic uplift. We find that rainfall rate changes produce unique slope change reversals near the headwaters, which differ from the simpler responses caused by uplift rate changes. These reversals are more pronounced when hillslope diffusion is dominant. These findings help us understand how climate and tectonic forcing shape the landscape differently and may allow scientists to tell their effects apart in nature.

We combine aerial and drone Light Detection and Ranging surveys with sediment export and density measurements to assess catchment-scale mass balance in a badland environment. Landslides and crest failures are found to contribute 15 % of total mass export while affecting only 1 % of bare surfaces. Flood-condition drainage reconstruction shows low-drainage areas export 3.5 times more sediment than other slopes.

On 13 June 2023, a freestanding rock pillar on the Matterhorn collapsed after years of weakening. Our study examines this progressive destabilization by analyzing field data and integrating lab experiments into a hydro-mechanical model. We highlight the critical role of water infiltration into frozen rock, intensified by climate warming, as a widespread driver of the rising frequency of rockfalls in high mountain permafrost regions.

We designed a novel surrogate bedload monitoring system that integrates phased microphone arrays and an accelerometer for enhanced performance. By combining beamforming-based localization with amplitude calibration, we demonstrate a viable approach to enhance the reliability of bedload measurements. These findings address the key question of whether impact-based acoustic systems can be refined to provide more accurate particle size estimates and offer conceptual and methodological advances.

Soil strength is influenced by wetness conditions, affecting slope stability, agricultural productivity, etc. Monitoring soil moisture is essential for risk management. We used Distributed Acoustic Sensing to monitor the deformation of a grass-covered slope over two summer months. We observed both long-term drying and daily "breathing" cycles: nighttime swelling and daytime shrinkage. By integrating strain and soil moisture data, we provide new field-scale insights into soil strength evolution.

This study explore the impact of landslides on Alpine terrain using a landscape evolution model called Hyland, which enables long-term topographical analysis. Our finding reveal that landslides are concentrated at two specific elevations over time and predominantly affect the highest and steepest slopes, particularly along ridges and crests. This study is part of a broader question concerning the origin of accelerated erosion during the Quaternary period.

To gain insight into the sediment transport onto a mid-channel bar in an estuary, we measured current velocities on and along the tidal flat during six months. Our analysis shows that intertidal currents have a more pronounced three-dimensional pattern than those on shore-connected tidal flats. This has consequences for sediment transport and morphodynamics. Existing models for tidal flats underestimate flow velocities and sediment dynamics on mid-channel bars.