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[Display omitted] • New empirical estimates are provided for monthly R-factors over Italy for 1981–2010. • R-factor is currently larger in autumn and summer, lower in spring and winter. • 29 EURO-CORDEX projections for 2021–2050 and 2051–2080 under three RCPs are used. • Future anomalies are critical in autumn (whole Italy), and in summer (North). • There is a large variability associated with the use of an ensemble of projections. The estimation of rainfall erosivity in the Revised Universal Soil Loss Equation (RUSLE) requires long series of sub-hourly rainfall observations. Due to the endemic unavailability of this information, at least with the required degree of detail and coverage, empirical models are frequently used for the estimation of rainfall erosivity basing on easily retrievable rainfall values at the monthly or annual scale. In this paper, an empirical model is calibrated for Italy to bridge the annual to monthly scale gap by means of 10-year series of monthly rainfall observations at 171 Italian rain gauges, and then applied using the ERA5-Land gridded rainfall dataset to obtain maps of monthly and seasonal rainfall erosivity covering the reference period 1981–2010. Successively, 29 EURO-CORDEX bias-corrected rainfall projections for two future horizons (2021–2050 and 2051–2080 under RCP 2.6, 4.5 and 8.5) are used to obtain expected anomalies of seasonal rainfall erosivity over Italy with respect to the reference period. Statistical and visual analysis of results shows that positive percentage anomalies are expected in large portions of the country, especially under RCP 2.6 but with significant increases expected also under RCPs 4.5 and 8.5, especially in autumn and, secondarily, in summer. This intra-annual rainfall erosivity anomaly pattern entails the existence of increasing trends in the erosion hazard that cannot be captured by empirical models only relying on annual rainfall. The position of those results in the related literature is deeply discussed, providing significant insights on uncertainty sources and possible future research developments. [ABSTRACT FROM AUTHOR]

Abstract: Including runoff in USLE-type empirical models is expected to improve plot soil loss prediction at the event temporal scale and literature yields encouraging signs of the possibility to simply estimate runoff at these spatial and temporal scales. The objective of this paper was to develop an estimating procedure of event soil loss from bare plots (length=11–44m, slope steepness=14.9–16.0%) at two Italian sites, i.e. Masse, in Umbria, and Sparacia, in Sicily, having a similar sand content (5–7%) but different silt (33% at Sparacia, 59% at Masse) and clay (62% and 34%, respectively) contents. A test of alternative erosivity indices for the Masse station showed that the best performances were obtained by the USLE-MM, originally developed at the Sparacia station. This model includes an erosivity index equal to a power (exponent>1) of the runoff ratio, QR , times the single-storm erosion index, EI 30. The fitted models at the two stations were found to coincide for highly erosive events (i.e., QREI 30 >6MJmmha−1 h−1). A parallelism of the two models was detected for low erosivity events. In conclusion, runoff was an important predictor of soil erosion, and local soil characteristics had a more noticeable effect on soil loss for events with a relatively low soil detachment and transport ability. A wider applicability of the USLE-MM scheme can be suggested than for the Sparacia station alone. Additional testing of the model in other environments and development of accurate procedures to estimate plot runoff coefficient at the event temporal scale are required. [Copyright &y& Elsevier]

Abstract: This paper reports the results of a field investigation aiming at characterizing the morphology and hydraulics of both rills and ephemeral gullies (EGs) monitored at Sparacia experimental area, Sicily, Italy. The comparison between rill and interrill erosion measurements showed that sediment delivery processes occurred in some erosive events and that the rill erosion rate was dominant in many cases. The measurements were used for testing both the empirical relationships between the channel (rill, EGs and gully) length and its eroded volume and among the morphological variables (length, width, depth and volume) describing the channelized process. Finally, the rill and EGs hydraulic geometry was modelled by three well known power equations relating the discharge with the mean flow velocity, with the flow depth and with the width of each channel segment, respectively. The rill measurements also showed that the flow velocity was affected by the rill segment slope while the flow depth and width were controlled by the plot slope. Therefore, three equations, taking into account these slope effects, were proposed to estimate the hydraulic characteristics of the rills monitored at the Sparacia area. [Copyright &y& Elsevier]

Abstract: The best possible model to predict the erosion from an area of land has been suggested to be a physical model of the area that has similar soil type, land use, size, shape, slope and erosive inputs. Therefore, a replicated plot has to be considered the best possible, unbiased, real world model. In this paper the physical model concept was tested by using soil loss data collected on plots of different length at the experimental station of Sparacia, in Sicily (South Italy). This investigation supported the conclusions that i) a coefficient of determination between measured and predicted soil loss values of 0.77 has to be considered as the best-case prediction scenario and ii) an uncalibrated deterministic erosion model would not give more accurate results than those obtained by a replicated plot measurement. An effectiveness coefficient of 0.47–0.49 was obtained by applying the original USLE to predict event soil losses at Sparacia. The difference between the value of 0.6, corresponding to what we can expect from an uncalibrated erosion model, and the effectiveness coefficient of the selected model represents the maximum gap that has to be covered to obtain the realistically best estimate of plot soil loss at the event temporal scale. [Copyright &y& Elsevier]

[Display omitted] • We tested a rapid workflow to estimate the anthropogenic reworked soil of terraces. • High-resolution topographic surveys enabled a detail assessment of terrace features. • Geomorphological features were fundamental to estimate terrace soil volumes. • Terrace volume estimation provides new benchmarks for soil erosion/C budget models. • The terrace volume data give new perspectives for management and preservation. High-resolution topographic (HRT) techniques allow the mapping and characterization of geomorphological features with wide-ranging perspectives at multiple scales. We can exploit geomorphometric information in the study of the most extensive and common landforms that humans have ever produced: agricultural terraces. We can only develop an understanding of these historical landform through in-depth knowledge of their origin, evolution and current state in the landscape. These factors can ultimately assist in the future preservation of such landforms in a world increasingly affected by anthropogenic activities. From HRT surveys, it is possible to produce high-resolution Digital Terrain Models (DTMs) from which important geomorphometric parameters such as topographic curvature, to identify terrace edges can be extracted, even if abandoned or covered by uncontrolled vegetation. By using riser bases as well as terrace edges (riser tops) and through the computation of minimum curvature, it is possible to obtain environmentally useful information on these agricultural systems such as terrace soil thickness and volumes. The quantification of terrace volumes can provide new benchmarks for soil erosion models, new perspectives to stakeholders for terrace management in terms of natural hazard and offer a measure of the effect of these agricultural systems on soil organic carbon sequestration. This paper presents the realization and testing of an innovative and rapid methodological workflow to estimate the anthropogenic reworked and moved soil of terrace systems in different landscapes. We start with remote terrace mapping at large scale and then utilize more detailed HRT surveys to extract geomorphological features, from which the original theoretical slope-surface of terrace systems were derived. These last elements were compared with sub-surface information obtained from the excavations across the study sites that confirm the reliability of the methodology used. The results of this work have produced accurate DTMs of Difference (DoD) for three terrace sites in central Europe in Italy and Belgium. Differences between actual and theoretical terraces from DTM and excavation evidence have been used to estimate the soil volumes and masses used to remould slopes. The utilization of terrace and lynchet volumetric data, enriched by geomorphometric analysis through indices such as sediment conductivity provides a unique and efficient methodology for the greater understanding of these globally important landforms, in a period of increasing land pressure. [ABSTRACT FROM AUTHOR]

Abstract: This paper examines the implications of changes in precipitation and land use to soil erosion from 1955 to 2002 in Basilicata, a hilly portion of southern Italy. Analysis of daily precipitation records reveals statistically significant trends using both non-parametric and parametric approaches. The inter-annual variability of precipitation increases in intensity; primarily between October and January. From 1955 to 2000, the length of dry spells greatly increased, while wet days decreased. A land use change map was produced for the three study areas using aerial photos (1955) and orthophotos (1997 and 2002), integrated with field surveys. Results show that land use is highly dynamic in Basilicata, especially due to the application of the European Union''s Common Agricultural Policy (CAP) measures. The EU policies resulted in reclamation of badlands and degraded grasslands for agriculture, principally the cultivation of durum wheat. This farming practice and the abandonment of some of the remodeled areas have increased the risk of soil erosion and desertification processes, and is manifest in land degradation by rill networks and gullying. [Copyright &y& Elsevier]