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Gully erosion is known to affect soil productivity, and to limit land use in many parts of the world. To assess the susceptibility of soils to gully erosion, the triggering factors must be analyzed. A simulation of gully development over time was implemented in Python – GIS modules based on the topographic characteristics of the study area, soil properties, and measured runoff. The results show that the developed modules allow a successful data preparation, process simulation and spatial visualization of the obtained results in 2D and 3D as well as an analysis of time series of gully evolution. [ABSTRACT FROM AUTHOR]

Badlands are unique soil erosion landforms distributed in numerous geological, geomorphological, and climate contexts in several Mediterranean countries. The aim of this study was to map, classify, and analyze the temporal evolution of the badlands that crop out between the Tesino and Tronto Rivers in the Marche region, Central Apennines (Italy). In this study, 328 badlands landforms were mapped through Google Earth, orthophoto analysis (year 2016), and field surveys. Moreover, badlands were classified from a morphological point of view based on the active processes detected in the field. Additionally, badlands were studied from a lithological point of view, meaning they were strictly related to the soft sedimentary formations of the study area. Subsequently, through the analysis of a 10 × 10 m DEM, the most significant morphometric indices were extrapolated and badlands were classified. Finally, through the orthophotos from 1988, another badlands dataset was created and the area of each landform was compared with respect to the orthophotos from 2016. The multi-temporal air photo analysis, combined with the NDVI results, identified a general reduction trend in badlands areas, with increases in green cover and dense vegetation and changes in badlands morphotypes. [ABSTRACT FROM AUTHOR]

We present a 1:50 000 scale geomorphological map of the upper Mkhomazi River basin, located in the foothills of the Drakensberg mountains in KwaZulu-Natal Province, South Africa. The sub-horizontal strata of the Permo-Triassic Beaufort Group forms plateau interfluves with a concave valley slope morphology. Locally, thick sequences of late Pleistocene colluvial deposits and associated buried paleosols (Masotcheni Formation) infill first-order tributary stream valleys and extend across the adjacent lower slopes. Surface runoff processes preferentially incise into the poorly consolidated, highly erodible sediments causing severe gully erosion that is responsible for widespread land degradation and desertification phenomena. The main purpose of this work is to derive a geomorphological map of the study area focussing on the erosional landforms to understand their spatial distribution and their relation to the colluvial deposits. Finally, a local and regional stratigraphic correlation of colluvial deposits and associated buried palaeosol profiles is proposed. [ABSTRACT FROM AUTHOR]

In this article we present a detailed litho-structural map of the Oltrepo Pavese, a sector of the Northern Apennines, Southern Lombardy, Italy. Lithology and geological structures are an important basis for different disciplines of Earth Sciences. In particular, for the assessment of earth surface processes such as soil erosion, mass movements, flooding, etc. The Oltrepo Pavese is characterised by a complex geology and related tectonic settings. In this study, we conducted a comprehensive lithological mapping approach considering existing geological maps, and detailed field surveys. The lithotypes have been subdivided into 11 classes based on the dominant outcropping lithologies. Integrating bibliographic data and a detailed Digital Terrain Analysis of a high-resolution DTM (5 m) we detected faults, folds and tectonic lineaments in the study area. The final result is represented by a litho-structural map of the Oltrepo Pavese-area, consisting in two shape files elaborated in an open source GIS environment. [ABSTRACT FROM AUTHOR]

One of the important electronic applications in recent years is organic - inorganic hybrid perovskite materials because of their many useful characterizations particularly the low cost, tunable optical properties and highefficiency. In this work we used varieties of lead halides, PbCl2 and PbBr2 to prepare two types of perovskites, MAPbBr3and MAPbBr2Cl by one step method then study their properties; structural, morphological and optical properties, to fabricate solar cells from these perovskites with preparation of TiO2 nanocrystal as electron transport material ETM by hydrothermal method. The power conversion efficiency PCE achieved is 1.2% and fill factor FF=0.26 for MAPbBr3 perovskite while the power conversion efficiency PCE for MAPbBr2Cl perovskite reached up to 0.9% and fill factor FF= 0.25. [ABSTRACT FROM AUTHOR]

• Sediment dynamics of a small watershed in the Northern Apennines was assessed. • The watershed is affected by rill-interrill and calanchi erosion. • A morphometrical characterisation of the basin was performed using a DEM. • A suspended sediments were assessed using a laser diffraction technique. • SSC and SMD were related to the available rainfall data. The volumes and dynamics of suspended sediments drained from a watershed are often unknown, especially in small creeks and tributaries where continuous discharge measurements are seldom available. The objective of this study was to assess in a qualitative and quantitative way the sediment dynamics of a small ungauged watershed in the Northern Apennines, Italy. We analysed and correlated the sediment volume concentration and grain-size distribution of the suspended sediments with the precipitation pattern. The study area is a small ungauged watershed (0.15 km2) that is dominated by intensive soil erosion processes and related landforms. The basin is oriented East-West with the south-facing slopes characterized by badland erosion processes. The north-facing slopes are cultivated and dominated by rill-interrill erosion phenomena. An morphometrical characterization of the basin was performed using a high-resolution DTM with a 1 × 1 m resolution. Subsequently, the physical characteristics of the topsoil were investigated based on grain size laboratory analysis. A detailed NDVI analysis of the vegetation was performed using Sentinel-2A images. Finally, we assessed the suspended sediments at the outlet of the basin using a laser diffraction technique. The Suspended Sediment Volume Concentration (SSC) and the Sauter Mean Diameter (SMD) of the eroded sediments, provide insights into the morphogenetic processes and the sediment transport dynamics of the basin. The measurements were conducted in autumn 2018 after an intense precipitation period and in spring 2019 after a dry phase. The results show a direct relationship between precipitation and SSC with a delay of about 2 h after the most intense precipitation events. Moreover, we reveal that the SMD values are inversely related to the precipitation due to turbidity effects. The SSC and SMD measurements allow for a detailed assessment of the dynamics between precipitation and suspended sediment load even though discharge volumes were not measured directly. [ABSTRACT FROM AUTHOR]