Environmental impact analysis of quarrying activities established on and near a river bed by using remotely sensed data

Several serious environmental impacts related to quarrying activities on and near the river, such as vibrations, land degradation, land subsidence and landslides, water pollution, occupational noise pollution, and air pollution, will lead to health-related problems and loss of biodiversity. Quarrying operations can adversely alter pre-existing ecosystems, and change hydrogeological and hydrological regimes. This adverse influence of stone and sand quarrying induces damage in property, depletion of ground water, loss of fertile topsoil, degradation of forests, deterioration in aquatic biodiversity and public health. On the other hand, haphazard quarrying of sand from riverbeds may cause a rapid change in bed configuration in response to the changes in flow. Quarrying basically destroys landscape. This can lead to downstream movement, scouring, or accumulation of sediment while provoking shoreline erosion. When riverbeds are composed of sand, this on-going pattern of erosion and deposition causes meanders to progress slowly downstream in time. In this study; change detection and environmental impacts due to stone and sand quarrying activities in the watershed area have been determined and evaluated using multi temporal Landsat 5 TM satellite images that were verified with ground truth data. These time series data on the extent of land in eco-sensitive areas were examined to assess the impact on environment. At the end of the study, thematic maps of the affected areas were created by using appropriate visualization and classification techniques in conjunction with geographical information system. Consequently, the changes on the mouth of the river were investigated by the impact analyses of quarrying activities established on and near upstream of the riverbed. Owing to this, a considerable extension in the shoreline around 400 m was observed on the river mouth in the study area.