Influence of Sheep Wool on Slope Greening

Abstract

Positive influence of wool mixed with soil on slope stability and its greening were examined. Mixtures of poor quality wool as well as polyester and polypropylene fibers with soil were obtained. The mixture was used to cover meandrically arranged ropes installed on the slope. After several weeks, intense greening of the slope was observed. Grass cover grown from seeds sown on the slope was very diverse, depending on types of fibers used for soil reinforcements. In places covered with soil mixed with wool, intense and dark green grass tillers were observed. In order to determine influence of wool on intense grass growth, progress of wool biodegradation was studied. Additionally, the content of different forms of nitrogen in soil during slope exploitation was analyzed. Wool biodegradation was investigated during observations with electron scanning microscope. It was revealed that biological damage of wool was accelerated by mechanical damage of fibers, that took place during bale opening and mixing wool with soil. As a result of biodegradation of wool keratin organic nitrogen was released. Due to ammonification process, it was converted into ammonium and later, via nitrification, into nitrate form. Both forms were available for growing grass and promoted its quick development.