Surveying the development of the steep-slope, terraced and mountainous viticultural landscape by using unmanned aerial vehicles: a costs & benefits analysis

We will present a reliable and low-expensive method to survey drywalls – the landscape marker of Val di Cembra (IT) – by using Unmanned Aerial Vehicles (UAVs) in order to quantitatively monitor the evolution of the underlying territory. For Val di Cembra, it is a matter of fact that the global warming, which makes better the grapes from the vineyards located at higher altitudes, in conjunction with the globalist wine market that pushes down the price of wines irrespective of their value, drive the choice of the vine growers to reshape large portion of traditional viticultural landscape removing the drywalls in order to benefit from lower operating costs thanks to mechanization. The key point is that the evolution of the landscape proceeds at an unprecedented speed, much faster than the studies describing the terraced vineyards landscape. The GIS softwares, that automatically detect the drywalls from the Digital Surface Models, terrifically speed up the landscape survey, but these methods rely on data acquisition campaigns which, due to their cost, are conducted only on a large spatiotemporal scale. Indeed, the regional or national data acquisition campaigns are repeated every five or ten years and can not intercept the evolution of the landscape over shorter periods. To tackle this gap, the use of drones seemed to us a viable idea as this tool has been successfully used in the topographic survey: with the appropriate measures during the planning and flight execution phase it is possible to effectively detect the quantitative characteristics (height and development linear) and qualitative (typology) of the (dry)walls and at low costs