Of cars and clay : the effect of offroad motoring on the rate of erosion over blue clay outcrops : case study : Selmun

Abstract

A current issue debated in the local press is the effects of offroad motoring on the local environment. This issue is bound to intensify due to the increasing interest in the sport. Various opposing arguments have been raised by both offroaders and environmentalists. However, no study has addressed this issue in a systematic manner. This research attempts to give a new dimension to this problem by assessing directly the effects of offroad motoring in relation to the rate of erosion over blue clay outcrops. The study is conducted at Selmun, one of the most offroaded sites in mainland Malta. The hypothesis is that offroad activities accelerate the rate of erosion by changing the physical properties of clay through compaction. This hypothesis is tested by laboratory experiments and field observations. Representative clay samples were analysed to assess the degree of compaction of the material. The experiments conducted in this regard are: bulk density, moisture content and shear strength. The experimental data obtained was finally related to the geomorphological context of the site under study. The social aspects of this issue are examined through a number of sources. A newspaper review yielded the main issues. These were extensively discussed through the application of questions and personal interviews with stake-holders involved in the Selmun debate.