Design of Terrace Drainage Networks Using UAV-Based High-Resolution Topographic Data

Abstract

Hillslope viticulture has a long history in Mediterranean Europe, and still holds important cultural and economic value. Steep hillsides have widely been levelled by terraces, in order to control surface water flow and facilitate cultivation. However, under unsustainable management and growing rainfall aggressiveness, terraced vineyards have become one of the most erosion-prone agricultural landscapes. The Valcamonica valley in Lombardy (Italy) presents a typical example of an ancient wine production region where rural land abandonment has previously caused widespread degradation of the traditional terracing systems. Recently, a local revival of wine production led to restoration plans of the terraces and their drainage functioning, to safeguard productivity and hydrogeologic safety. In this study, an Unmanned Aerial Vehicle (UAV) survey was carried out to reconstruct an accurate and precise 3D terrain model of a Valcamonica vineyard through photogrammetry. The resulting high-resolution topographic data allowed insights of surface flow-induced soil erosion patterns based on the Relative Path Impact Index (RPII). Three diverse drainage networks were designed and digitally implemented, allowing scenario analysis of the costs and benefits in terms of potential erosion mitigation. The presented methodology could likely improve the time-efficiency and cost-effectiveness of similar restoration plans in degraded landscapes.

Estimating soil degradation in montane grasslands of North-eastern Italian Alps (Italy)

“…Such methodology was then tested in two study areas, through SfM photogrammetric technique (now a well-established methodology for the analysis of surface morphology; Eltner et al., 2016; Pijl et al., 2019; Sofia et al., 2017). According to this technique, two Digital Elevation Models (DEMs) were created and then processed to estimate the volume of eroded soil.…”

Farmers’ landslide risk perceptions and willingness for restoration and conservation of world heritage site of Honghe Hani Rice Terraces, China

“…However, this relationship does not always see an equilibrium, affecting many agricultural terraces worldwide (Tarolli et al 2014). Land abandonment, mismanagement and inadequate maintenance are one of the most common problems that can turn into hydrogeological dysfunctions and soil erosion overall (Pijl et al 2019;Tarolli and Straffelini 2020). Landslides are quite common phenomena affecting agricultural heritage terraces causing severe damages: from the Machu Picchu archaeological site in Peru (Sassa et al 2003;Klimeš 2013), the Cinque Terre in Italy (Agnoletti et al 2019;Brandolini et al 2018) and the Slovakian and Greek landscapes (Canuti et al 2009).…”

Slope instabilities in steep cultivation systems: Process classification and opportunities from remote sensing

“…The study areas present a wide geographical distribution in the world (Figure 2), and gully erosion and landslides are the most studied processes in steep agricultural zones. Most of these case‐studies are located around the Mediterranean basin, especially in Spain and Italy where slope failures are often the consequences of land‐use changes (Prosdocimi et al, 2016) and abandonment of farming practices (García‐Ruiz & Lana‐Renault, 2011; Koulouri & Giourga, 2007) especially in terraced areas (Arnáez et al, 2015; Tarolli et al, 2014), or lack of maintenance of drainage networks (Lesschen et al, 2008; Pijl, Tosoni, et al, 2019; Tarolli et al, 2019) and the increasing occurrence of high‐intensity rainfall events after long periods of drought. Mediterranean environments are particularly prone to mass movement due to high rainfall intensity combined with low average annual precipitation, the fragility of many soils, and the presence of very steep agricultural slopes in extreme environments (García‐Ruiz, 2010).…”