Quick scoping review on the impact of sand mining activities on freshwater ecosystem, hydraulic regime and river morphology

Abstract

Sand mining is a worldwide environmental threat that is gaining media's attention. Sand and gravel are the most important materials for building construction. However, excessive withdrawal from the river system may cause irreversible damages to the ecological and socio-economics in the long run. As demands for stronger regulation of mining develop, the scientific evidence needs to be understood in order to justify the effectiveness of the management. The mining process not only induced channel incision, but also disrupted sediment balance in the area whereas, the sediment loads responsible for the changes of the banks that lead to exposure of underlying grain, deteriorating the water quality and encroaching the abundance of species habitats. By using Quick Scoping Review (QSR), the aim for this paper is to provide a summary of various studies on the impacts practice of sand mining either positively or negatively on the environment, aquatic habitat, biodiversity and hydraulic regime of the river system. It was found that negative impacts and significant alteration were dominant opposed to the positive impacts. Channel incision, loss of habitat and sedimentation at downstream areas were identified as direct impact due to sand mining activities. QSR results show that response river ecosystem to sand mining is complex. The documented collected response showed that channel incision contributes the most impact due to sand mining activity at the river, followed by sediment fluctuation on river bed. However, self-sustaining of river to dynamic equilibrium will give little help to reduce the negative impact of sand mining activities but self-adjustment process acquires longer time than the former. These findings may help authorities on planning the best management practice for sustainable mining activities in the and nurture the importance of preserving river ecosystem and providing mitigation plan in future.