Does the trail matters? - In search of the environmental impact of hiking trails on the hillslope runoff.

Background: In the late 20^th century great advancement was made in the field of hiking trail studies. The main concerns for these trails are susceptibility to soil erosion and dynamic landform changes in their nearest area. The impacts of the trails for vegetation were also studied with trampling and soil exposure being the most destructive. Today, With the higher and higher resolution for digital terrain models being available and advanced simulation algorithms and computing, it is possible to perform advanced modeling of a hillslope runoff.

The aim: The aim of these studies is to determine the impact of hiking trails on hillslope water runoff by comparison of the water discharge values during simulated precipitation events.

Method: The comparison is made possible, with the use of digital terrain modeling to create hillslope with and without a hiking trail, in its pre-erosion state. Both models then are subject to Simulated Water Erosion (SiMWE) based on the Monte Carlo simulation method. The algorithm is implemented in an open-source GRASS GIS program in the form of r.sim.water and r.sim.sediment modules. Exemplary hillslopes also present different scenarios based on the trail to slope alignment angle (0° - 22°; 22,1° - 45°; 45,1° - 67° and 67,1° - 90°). 

During the session a case study area of a suburban mountain range within Kielce city (Poland) will be introduced, together with the results of simulation values and their spatial distribution for the exemplary hillslopes. With it, the role of the hiking trail and its environmental impact on water runoff will be better understood and easier to predict.