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Agricultural terraces represent one of the best ways to prevent land degradation in hilly and mountainous landscapes. However, it is widely recognized that terraced slopes are threatened by agricultural land abandonment. In the literature, very few studies have quantitatively examined the influence of agricultural abandonment on the stability of terraced slopes. The goal of this research is to investigate the relationships between landslide magnitude and land use conditions of agricultural terraced slopes. In particular, Light Detection And Ranging (LiDAR) elevation data, coupled with aerial photo interpretation, were used for the computation of shallow landslide mobilized volumes on terraced slopes affected by an intense rainfall event. We performed the analysis within the Vernazza basin, a small Mediterranean coastal catchment located in the “Cinque Terre” area (Liguria, northwestern Italy), comparing pre‐event and post‐event LiDAR datasets. The results revealed that abandoned terraced slopes have been affected by a higher amount of mobilized debris volumes than still‐cultivated terraces. Furthermore, terraces abandoned for a short time (less than 25–30 years) resulted in the most hazardous land use class, showing erosion rates that were approximately 2 and 3 times higher than terraced slopes abandoned a long time ago (more than 25–30 years) and still‐cultivated terraces, respectively. These findings highlight that land abandonment and agricultural mismanagement can intensify the magnitude of rainfall‐induced shallow landslides. Copyright © 2016 John Wiley & Sons, Ltd.

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In recent years, much research have dealt with the impact of human and climate change on the morpho-evolution of Mediterranean catchments characterized by high ecological and cultural value. In this paper, we speculated how humans can influence hillslope degradation by reviewing the relationships between denudation processes and land use changes in some representative areas located in different Italian regions (i.e., Liguria, Tuscany, Basilicata, and Sicily). The selected study cases are characterized by different climatic and geological features, land use, and land management and can be considered indicative of the hillslope degradation issues that affected the Apennines during the last century. We compared and discussed the main outcomes from previous studies, with the aim of identifying the main drivers leading to hillslope degradation and to shed light on the role of human action. We revealed that hillslope degradation can be mainly related to deforestation for land reclamation, cropland abandonment, and the increase of hazardous rainfall. Moreover, we focused on how human impact can have both positive and negative feedbacks. In some cases (e.g., badlands), the land levelling has produced an initial inhibition of land degradation, whereas after intensive agricultural practices, accelerated soil depletion has occurred, favouring erosion processes. Analogously, terracing controlled erosion as long as the entire terrace system was maintained, but abandoned terraced slopes can increase the magnitude of geo-hydrological phenomena in response to high-intensity rainfall.On-the-other-hand, both rural landscape and related erosional landforms can be appreciated as elements of landscape diversity and contribute to tourism development.

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