Effects of topsoiling on rates of erosion and erosion processes in coal mine spoil banks in Utrillas, Teruel, Spain

Runoff production and soil erosion, produced by energetic Mediterranean storms, are amongst the first environmental impacts of opencast mining activity and amongst the main limiting factors in achieving self-sustaining reclaimed landscapes in Teruel. This paper aims to understand the geomorphological response of topsoiled and overburden-covered banks. This is considered essential in improving soil management and designing accurate erosion control plans. Runoff and erosion rates were recorded after every rainfall in permanent plots for one year in both overburden and topsoiled banks. In the same way experiments were conducted with a portable rainfall simulator to follow the response evolution throughout time. Grass communities control topsoiled bank evolution, leading to an improvement in the hydric characteristics of the topsoil during ecological succession. Physical-chemical soil properties condition the erosion processes in overburden-covered banks. No improvement in infiltration rate nor in erodibility has been recorded 6 years after the slope banks were constructed.