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Our aim is to characterize patterns of evolution of morphological units on the nucleus of 67P-CG such as pits, sink-holes or, more generally, pit-like features. This work focuses on developing suitable metrics to contrast different stages and changes during the time evolution. We adopt a 3D mass-loss evolution model (MONET) assuming water ice sublimation is the primary driver of erosion activity. This paper considers isolated pit-like structures without the process of merging which will be addressed in our subsequent work. The modelling study cases investigate how latitude, obliquity, and initial pit shape converge in defining the final morphology of the pits, for a spherical nucleus as well as shape model of 67P/C-G. Our results corroborate to some extent the previous studies quantifying exes heat retention due to the concavity of these pit features, however, we demonstrate a clear dependence of 'smoothing' or 'deepening' effects on the orientation and initial shape. Furthermore, it is shown that the diameter evolution of the pits is influenced by a combination of factors such as solar incidence, shadowing, and/or self-heating acting on its walls. Under certain circumstances, we also observe pronounced asymmetry in mass-loss at the pit floors, a weak effect of terracing. Mass-loss-induced evolution may result in the transformation of circular depressions into elongated ones due to specific solar illumination directions. The modelling results presented here represent the first explicit simulators of the deepening, widening, and smoothing processes in the context of 67P-C-G. [ABSTRACT FROM AUTHOR]

Soil erosion is a major environmental concern, especially in sensitive ecosystems like the Loess Plateau of China, where certain geological and climatic circumstances exacerbate the erosion process. Terracing and mulching are popular soil erosion management strategies in this region. However, their combined effects under varied rainfall intensities are poorly understood. The purpose of this study is to assess the performance of various terracing–mulch combinations in reducing water erosion under different rainfall intensities. The experimental layout included a control plot (C), non-terraced mulch applications (NTr-M), fish-scale pits with mulch (FSPs-M), zig terraces with mulch (ZTr-M), level bench terraces with mulch (LBTr-M), and trench terraces with mulch (TTr-M). Controlled artificial rainfall experiments were carried out under different intensities, and runoff and soil loss data were collected to evaluate the effects of the combinations. The event-based WEPP simulations, calibrated for the Loess Plateau, demonstrated strong predictive accuracy, as evidenced by the high correlation coefficients (R2 = 0.97 for runoff; R2 = 0.86 for soil loss) and Nash–Sutcliffe efficiency (NSE = 0.93 for runoff; NSE = 0.89 for soil loss), confirming their reliability in simulating erosion processes when compared to measured values. Our results revealed significant differences (p < 0.05) in mean runoff and soil loss among the treatments, ranked in the order LBTr-M < TTr-M < ZTr-M < FSPs-M < NTr-M < C. Incremental response analysis also revealed that the control plot (C) was the most sensitive to changes in rainfall intensity, followed by FSPs-M and NTr-M. In contrast, LBTr-M was found to be the most stable strategy. These findings highlight the importance of optimizing micro-relief construction and mulch application to enhance erosion control and support the recommendation of LBTr-M, TTr-M, and ZTr-M as effective strategies. Conversely, FSPs-M and NTr-M proved less effective under higher rainfall intensities. These findings emphasize the need to optimize micro-relief construction and mulch application for erosion management, as well as suggest that such strategies could be applied to the Loess Plateau and other erosion-prone regions worldwide with similar climatic and topographic conditions. [ABSTRACT FROM AUTHOR]

Soil erosion is a major environmental concern, especially in sensitive ecosystems like the Loess Plateau of China, where certain geological and climatic circumstances exacerbate the erosion process. Terracing and mulching are popular soil erosion management strategies in this region. However, their combined effects under varied rainfall intensities are poorly understood. The purpose of this study is to assess the performance of various terracing–mulch combinations in reducing water erosion under different rainfall intensities. The experimental layout included a control plot (C), non-terraced mulch applications (NTr-M), fish-scale pits with mulch (FSPs-M), zig terraces with mulch (ZTr-M), level bench terraces with mulch (LBTr-M), and trench terraces with mulch (TTr-M). Controlled artificial rainfall experiments were carried out under different intensities, and runoff and soil loss data were collected to evaluate the effects of the combinations. The event-based WEPP simulations, calibrated for the Loess Plateau, demonstrated strong predictive accuracy, as evidenced by the high correlation coefficients (R2 = 0.97 for runoff; R2 = 0.86 for soil loss) and Nash–Sutcliffe efficiency (NSE = 0.93 for runoff; NSE = 0.89 for soil loss), confirming their reliability in simulating erosion processes when compared to measured values. Our results revealed significant differences (p < 0.05) in mean runoff and soil loss among the treatments, ranked in the order LBTr-M < TTr-M < ZTr-M < FSPs-M < NTr-M < C. Incremental response analysis also revealed that the control plot (C) was the most sensitive to changes in rainfall intensity, followed by FSPs-M and NTr-M. In contrast, LBTr-M was found to be the most stable strategy. These findings highlight the importance of optimizing micro-relief construction and mulch application to enhance erosion control and support the recommendation of LBTr-M, TTr-M, and ZTr-M as effective strategies. Conversely, FSPs-M and NTr-M proved less effective under higher rainfall intensities. These findings emphasize the need to optimize micro-relief construction and mulch application for erosion management, as well as suggest that such strategies could be applied to the Loess Plateau and other erosion-prone regions worldwide with similar climatic and topographic conditions.

This study investigates the recent tectonic evolution of coastal landscapes, focusing on integrating fossil tidal notches and fossil marine terraces as tools for coastal tectonic studies in the Capo Rama promontory (central Mediterranean, southern Italy, NW Sicily). These geomorphological features are crucial for understanding the tectonic forcings that shape coastal landscapes (e.g. active faulting or regional uplift), especially in the context of the high resolution topographic and morphometric data available today. This research addresses a significant gap in the current understanding of the combined use of these markers to study the evolution of the coastal landscape and its tectonic drivers. The aim is to elucidate the interplay between coastal geomorphology and tectonics in areas with elusive tectonic activity (i.e., regions deforming at a rate lesser than 1 mm/yr), hosting previously undetected seismogenic sources and, for that reason, assumed as having low seismic hazard. Employing a multidisciplinary approach, the study integrates surveys conducted along the emerged and submerged coastline with analytic/statistical morphometric analyses and fault modelling. This methodology offers a comprehensive view of the elevation and distribution of MIS 5.5 littoral deposits and coastal geomorphological markers such as marine terrace inner edges and tidal notches. Key findings reveal substantial elevation differences in these markers, varying between +34 and +1.9 m above sea level along a north-south transect, highlighting an active seaward tilting in the study area. Such tilting is related to the Quaternary deformation of a previously unknown buried fault crossing the study area. Achieved outcomes allowed exploring the integration of tidal notches and marine terraces' inner edges as geomorphological markers for coastal tectonic analyses. Moreover, this study lays foundations for future research, enabling a more detailed understanding of the hypothesized buried fault, and its contributions to the understanding of the active faulting processes in the southern Tyrrhenian region. • Focus on the joint use of tidal notches and marine terraces for coastal tectonic • A swim survey approach to map late Quaternary tectonic markers • A best-fit approach to parametrize a previously unknown active fault • New information on the southern Tyrrhenian tectonic framework [ABSTRACT FROM AUTHOR]

The Western Iberian Peninsula is undergoing compressive tectonic reactivation, resulting in spatial and temporal variations of surface uplift. Uplift quantification can be undertaken in coastal settings using staircases of shore platforms developed onto rocky headlands. This study analyses two marine terrace staircases in central Portugal: Cape Raso - Abano beach and Cape Espichel. Geomorphic and stratigraphic analyses identified marine terraces/shore platforms developed below a culminant shore platform, four at Cape Raso and eleven at Cape Espichel. The terrace chronology was obtained by using ESR and pIRIR dating. Using the interactions between the elevation, age and global mean sea-level elevations, the marine terraces were correlated with Marine Isotope Stages (MIS). The shore platforms at the Cape Espichel are more elevated than the coeval references at the Cape Raso - Abano beach and this indicates differential uplift. Considering the culminant shore platform (3.7 Ma), for the Espichel W promontory the estimated long-term uplift rate is ∼0.03 m/ka, but for the Cape Raso is only ∼0.01 m/ka. Also, by using the shore platform considered as produced by the MIS 15 high stand (∼572 ka), the estimated uplift rate for the Espichel W promontory is ∼0.13 m/ka, but for the Cape Raso is ∼0.07 m/ka. The Espichel W promontory terrace staircase also allows to deduce that the estimated uplift rate was nearly constant during ∼600 ka to ∼200 ka ago (∼0.13–0.11 m/kA), but it after decreases (∼0.06–0.01 m/ka). [ABSTRACT FROM AUTHOR]

This paper is devoted to studying the existence of traveling wave solutions for reaction-diffusion equations with fractional Laplacians in time-periodic environments. By developing a dynamical systems approach, we establish the existence of propagating terraces for equations with multistable nonlinearities, which consequently implies the existence of bistable traveling waves. Furthermore, we investigate whether traveling waves exist in the multistable case. We provide an affirmative answer to this question for a special type of nonlinearity in high-frequency oscillating environments, and determine the homogenized limit of the traveling waves as the period approaches 0. [ABSTRACT FROM AUTHOR]

As urbanization and industrialization surge in China, the problem of land abandonment intensifies. However, the situation of terrace abandonment in China remains unclear. We conducted the first-ever remote sensing monitoring of terrace abandonment in China with full space coverage by combining high-precision terrace data with land use datasets to reveal the abandonment pattern. By fully considering natural and socio-economic factors, the XGBoost-SHAP framework was used to investigate the driving factors of terrace abandonment. The results show that approximately 2.42 % of terraces were abandoned from 2019 to 2021, mainly distributed in the Southwest and Loess Plateau regions. Agricultural regions with more terraces exhibited higher abandonment rates. The ratio of the population with pension insurance, cropland quality, slope, and land parcel size were prime drivers of terrace abandonment. There were significant spatial differences in the contribution of each factor. It is noteworthy that there was a significant deceleration in terrace abandonment trends in 2021, potentially ascribed to the impact of the COVID-19 pandemic leading to a substantial decrease in non-agricultural employment opportunities, thereby slowing down rural-to-urban emigration and even prompting a return migration of migrant workers. Grasping this critical post-pandemic period is crucial and should support returning migrant workers in engaging in agricultural activities by establishing diverse new agricultural entities and providing agricultural technical guidance. • China's terrace abandonment pattern was monitored with full space coverage. • About 2.42 % of terraces were abandoned from 2019 to 2021. • Driving forces vary significantly across various regions and types of cropland. • The post-pandemic is a critical period for promoting cropland reclamation. [ABSTRACT FROM AUTHOR]