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For thousands of years, humans have altered the movement of water through construction of earthworks. These earthworks remain in landscapes, where they continue to alter hydrology, even where structures have long since been abandoned. Management of lands containing earthworks requires an understanding of how the earthworks impact hydrology and knowledge of where the structures are located in the landscape. Various methods for detecting topographic features exist in the literature, including a set of rule and threshold‐based techniques and machine learning methods. These tools are either labor‐intensive or require special pre‐processing or a priori assumptions about structures that limit generalizability. Here, we test a topological analysis tool called “persistence” to determine if it is useful for earthwork detection in rangelands. We found that persistence can be used to detect earthworks with 83% precision and 64% accuracy. Breached berms and berms with significant upslope sedimentation are most likely not to be detected using persistence. These results indicate that persistence can be useful for terrain analysis, and it has the potential to substantially reduce manual effort in feature detection by identifying regions where berms may be found. Plain Language Summary The shape of landscapes controls how water moves over the surface. Humans have modified landscapes by building earthen structures to direct water for thousands of years. The legacy of human water management systems remains in many places around the world, and land managers need to understand how these structures impact hydrology and where they are in order to support management decisions. Earthen dams, berms, and stock ponds dot the southwestern United States. High‐resolution elevation maps and imagery are increasingly available, and although man‐made structures are readily visible to the eye, automatic detection remains a challenge. In this study, a method from the mathematical field of topology called “persistence” was applied to automatically detect berms and stock ponds from elevation arrays. This method identifies features from a series of binary images generated from the same elevation map at consecutive threshold values. Results demonstrate that persistence is able to detect well‐defined berms. While not all berms are detected, these results are still promising since berms are generally found in groups. Thus, detection of even two thirds of the berms substantially narrows down regions for manual inspection. Key Points Persistent cohomology can be used to summarize topographic information A persistence threshold is adequate to identify berms and stock ponds from focused regions A set of criteria calculated from persistence can detect 64% of observed berms

Coelho, C., Ferreira, A.M. and Lima, M., 2024. Numerical modeling of artificial nourishments on the beach profile: Effects on reducing dune overtopping. In: Phillips, M.R.; Al-Naemi, S., and Duarte, C.M. (eds.), Coastlines under Global Change: Proceedings from the International Coastal Symposium (ICS) 2024 (Doha, Qatar). Journal of Coastal Research, Special Issue No. 113, pp. 599-603. Charlotte (North Carolina), ISSN 0749-0208. Reports of overtopping and flooding due to the shoreline retreat are becoming more frequent. Artificial sediment nourishments are used to mitigate erosion and overtopping problems, as they protect ecosystems and infrastructures and can be relevant for tourism, by expanding the beach areas for recreational use. However, the performance of these interventions depends on the volumes of sand considered and the deposition location on the cross-shore profile, among other factors. Through the application of the CS-Model, the performance of several artificial sand nourishment scenarios was evaluated, in order to reduce the frequency of coastal overtopping. The results indicate that raising the dune combined with reinforcement of the landward dune face is the most effective solution. The work provides important information for coastal management to support decision-making in artificial nourishment interventions.

The efficiency of beach recovery during a time of moderate waves following storm waves is closely related to the interaction between dynamics, sediment, and the landform. The existing studies mainly focus on the description of erosion and accretion characteristics, while the response and feedback mechanism of beach berm sediment have not been elucidated. The main controlling factors of recovery efficiency are not clear. In this paper, field observation and the XBeach numerical model are utilized on the sandy beach in Puqian Bay, China, to capture high-frequency cross-shore data during the post-storm recovery period. The variation characteristics and rules of berm elements, including berm ridge height and slope on two sides of the berm ridge, are analyzed. It is observed that the berm constantly changes to adapt to dynamic conditions. Additionally, a correlation between volume change and certain landform parameters is proposed, leading to the identification of a new relationship in wave run-up. The new forum reflects berm influence and considers the berm ridge and berm width.

In order to increase the capacity of landfills while ensuring a certain degree of stability of such structures, an engineered berm is typically constructed at the front slope of the landfill. For this type of landfill slopes, this paper primarily focuses on the construction and verification of stability assessment models for such structures. Initially, the calculation models of the safety factor were established, considering over and under berm failure modes separately. Subsequently, through error analysis, it was determined that it is feasible to evaluate the stability of this type of landfills by substituting the true safety factor with the average safety factor obtained from the calculation model. The analysis for parameters and slip surfaces was then conducted to investigate the impact of parameters associated with the engineered berm on the landfill slope stability. Finally, a visual comparison and brief discussion were conducted on the average safety factors under translational and composite failure modes. Thus, the critical failure modes under specific working conditions can be reasonably ascertained, which holds significant practical implications for enhancing the reliability of stability assessment of such landfill slopes.

Coal production in opencast mining generates substantial waste materials, which are typically delivered to an on-site waste dump. As a large artificial loose pile, such dumps have a special multi-berm structure accompanied by some security issues due to wind and water erosion. Highly accurate digital surface models (DSMs) provide the basic information for detection and analysis of elevation change. Low-cost unmanned aerial vehicle systems (UAS) equipped with a digital camera have become a useful tool for DSM reconstruction. To achieve high-quality UAS products, consideration of the number and configuration of ground control points (GCPs) is required. Although increasing of GCPs will improve the accuracy of UAS products, the workload of placing GCPs is difficult and laborious, especially in a multi-berm structure such as a waste dump. Thus, the aim of this study is to propose an improved GCPs configuration to generate accurate DSMs of a waste dump to obtain accurate elevation information, with less time and fewer resources. The results of this study suggest that: (1) the vertical accuracy of DSMs is affected by the number of GCPs and their configuration. (2) Under a set number of GCPs, a difference of accuracy is obtained when the GCPs are located on different berms. (3) For the same number of GCPs, the type 4 (GCPs located on the 1st and 4th berms) in the study is the best configuration for higher vertical accuracy compared with other types. The principal objective of this study provides an effective GCP configuration for DSM construction of coal waste dumps with four berms, and also a reference for engineering piles using multiple berms.

Beach recovery describes the processes by which there is a natural restoration of beach material and coastal morphology following storm events, and these processes are common across the globe. However, the effects of beach recovery on salinity distribution and solute transport in unconfined coastal aquifers are poorly understood. This study examined the changes in salinity distribution in tidally influenced aquifers in response to beach recovery, based on numerical modeling. The extent and location of the upper saline plume and saltwater wedge were found to vary with the beach recovery. The variations in salinity distribution directly changed the particle travel times in the aquifers. Compared with the erosion profile after the storm (storm profile), an increase of up to 743% of the particle travel time in the intertidal zone was observed when the beach recovered to a berm (silting) profile. The berm profile increased the residence time and peak concentration of the land-sourced solute plume in the beach aquifer compared with the storm profile. The berm profile also enhanced the aquifer–ocean mass exchange, resulting in increased intertidal saltwater infiltration and submarine groundwater discharge. On the other hand, the storm profile can generate much higher solute efflux than the berm profile. The storm profile is more favorable in diluting the land-sourced conservative solute and shortening its residence time in an aquifer.

Increasing interest in deploying multiple types of sensing instruments for agricultural plot‐level observations has created a need for simple, high‐clearance vehicles that can be easily maneuvered through crops while minimizing damage due to wheel traffic. We describe a simple cart built from a 2‐m‐wide by 1.2‐m‐long steel frame that was welded onto two bicycle frames at a height providing 1 m of vertical clearance. Instruments such as radiometers and infrared thermometers are attached to the frame via arms that are secured with U‐bolts. A large, horizontal surface allows mounting data loggers, batteries, or computers. The cart is easily maneuvered by one person on level ground or by two persons on terrain with furrows, berms, or other obstacles. Design sketches and lists of materials are provided in an electronic supplement. The basic design is readily modifiable for different interrow spacings and sensor positions.

Geotextile is a geosynthetic-based soil stabilization technique recently used to reinforce the soil and stabilize the canal slopes. In this study, the effect of using different nonwoven geotextile configurations on soil reinforcement and slope stability for irrigation canals subjected to loads on a canal berm was experimentally and numerically investigated. First, a laboratory model was constructed, the materials were prepared, and testing procedures were performed. The experiments were conducted to investigate settlement due to footing loads of width B acting on a canal berm in a dry case under different scenarios of geotextile soil reinforcement. Different lengths ( l  = 1.5, 2.0, and 4.0 B ) and depths ( d  = 0.5, 1.0, and 2.0 B ) of geotextile layers were used. Second, the experimental data were used to calibrate and validate the PLAXIS-3D model. Third, a series of simulation scenarios were conducted to investigate the joint effect of geotextile configurations on settlement. After that, the PLAXIS-3D model was used to determine the factor of safety (FoS) of the Ismailia Canal (i.e., real case study) side slope under different loading conditions with and without geotextile reinforcement. Finally, a cost analysis was conducted for Ismailia Canal under different geotextile configurations. Results showed a close agreement between experimental and PLAXIS-3D simulation results. Results also showed that geotextile reinforcement enhances bearing capacity ratio (BCR) and reduces settlement. As the length of the geotextile layer increases, the BCR increases and the settlement decreases. Among the investigated geotextile configurations, the optimum configuration was found when l  =  4 B and d  =  B . In addition, soil reinforcement by geotextile for Ismailia Canal under an excavator load of 40 tons lowered the settlement values by about 10%, whereas its effect on the slope stability FoS was almost inconsiderable. Therefore, geotextile reinforcement can be used to relatively reduce settlement near canals’ embankments.

An exceptional July 2022 winter storm brought 550 mm of precipitation to the Southern Alps of New Zealand. A series of alpine mass movements occurred during the storm, including a widespread snow avalanche cycle, debris flows, and erosion from rain runoff. We detail the sequence of events in the Kitchener avalanche path. Here, two large snow avalanches were followed by a debris flow. Substantial erosion of deposition and the underlying alluvial fan were induced by runoff from over 300 mm of rain falling after the first avalanche. The Kitchener path saw the largest avalanche since 1986, testing the utility of a diversion berm constructed for a 1:100‐year event. Results from a unmanned aerial vehicle lidar survey and numerical modeling characterize the rain‐on‐snow hazard sequence. In particular, the rain‐on‐snow event occurred on a deep mid‐winter snowpack, offering insights into future hazards posed by increasingly frequent extreme alpine precipitation. Plain Language Summary Intense rain and snow in alpine regions can trigger snow avalanches, debris flows and other mass‐movements, posing risks to people and infrastructure. This study documents an extreme hazard sequence triggered by a record‐breaking winter rainstorm in the Southern Alps of New Zealand. A drone was used to map deposition from snow avalanches and a debris flow that ran along a diversion berm designed to protect Aoraki/Mount Cook Village from a 1:100‐year avalanche. The mapping was used to calibrate avalanche modeling software that could replicate key characteristics of the snow avalanches and provide insight into flow dynamics. The documentation and results from the modeling can be used to plan for future hazards triggered by intense rain falling on a winter snowpack, which is particularly important in the face of a warming climate. Key Points Record‐breaking winter storm bringing rain to high elevations triggered a series of alpine mass movements in New Zealand's Southern Alps Snow avalanches were successfully diverted away from Aoraki/Mount Cook Village in the largest avalanche cycle observed in decades Event documentation and modeling help anticipate future hazards for such rain‐on‐snow induced mass movements on deep mid‐winter snowpacks

Major differences in beach erosion between two neighboring artificial beaches Xiangluwan Beach (XL beach) and Meiliwan Beach (ML beach) in Zhuhai, China, were studied after Super Typhoon Hato. In this study, a fully nonlinear Boussinesq wave model (FUNWAVE)-Total Variation Diminishing (TVD) was used to distinguish the main impact factors, their relative contributions, and the hydrodynamic mechanisms underlying the different beach responses. Results show that compared to the ML beach, the main reason for the relatively weak erosion on Xiangluwan (XL) beach was the smaller beach berm height (accounting for approximately 75.9% of the erosion response). Regarding the beach with a higher berm, the stronger wave-induced undertow flow, along with the higher sediment concentration, led to a higher offshore sediment transport flux, resulting in more severe erosion relative to the beach with a smaller berm height. The second most important reason explaining the weak erosion on XL beach was the absence of seawalls (accounting for approximately 17.9% of the erosion response). Wave reflection induced by the seawall could cause higher suspended sediment concentration, resulting in a toe scouring near the seawall. The offshore submerged breakwater protected XL beach slightly (accounting for approximately 6.1% of the erosion response). Due to the higher water level induced by storm surge, most of the wave energy could penetrate through the submerged breakwater. The effect of the larger berm width of XL beach was negligible. Compared to the beach with a larger berm width, the erosion/deposition regions in the beach with a narrower berm width showed shoreward migration, without significant changes in the erosion/deposition extent. Despite of this, the larger berm width could reduce the wave energy reaching the shoreline. This study of the storm stability of artificial beaches may be applied to beach restoration design.