Terraced landscapes: From an old best practice to a potential hazard for soil degradation due to land abandonment

• Overview of the available literature on terraced landscapes in different region of the world.
• Three Italian case studies located in three different contexts were considered.
• Critical issues (terrace failures) related land abandonment were described and analyzed.
• Non-structural and structural management were described.
• The review underlines also the likely future challenges about terrace management with lidar.

Among the most evident landscape signatures of the human fingerprint, the terraces related to agricultural activities are of great importance. This technique is widely used in various parts of the world under various environmental conditions. In some areas, terraced landscapes can be considered a historical heritage and a cultural ecosystem service to be adequately preserved. However, terraced landscapes subject to abandonment can progressively increase gully erosion and cause terrace failure. Partly because of changes in societal perspective and migration towards metropolitan areas, some countries have been affected by serious and wide abandonment of agricultural lands in recent decades. This review aims to discuss the current state of agricultural terraced landscapes, underlining critical issues and likely solutions. The paper is structured in three main sections. The introduction provides an overview of the available literature on terraced landscapes and their critical issues. The second section presents three case studies: the first is located in the so-called Cinque Terre area (Liguria, Northern Italy), the second is placed in the Chianti Classico area (Tuscany, Central Italy), and the third refers to the renowned Amalfi Coast (Salerno, Southern Italy). The last section of the review relates to likely solutions (non-structural and structural management) and future challenges (use of high-resolution topography derived by lidar) for suitable management of such environments.