Impacts of land use change on the sedimentation of the Mangla reservoir, Pakistan

Abstract

The problem might seem quite simple to analyse at a local scale; however, the sediment yield of a river basin is affected by other factors, such as surface run-off, temperature, slope stability, making the sedimentary processes more complicated to model and requiring basin scale approaches. The multipurpose Mangla Reservoir, in Pakistan, is losing its storage capacity at a yearly rate of about 0.5 % (1,970 million of m3 lost between 1967 and 2010, before up-raising the dam in 2011). The impacts of land use changes in the Mangla Dam basin were assessed, showing that the current trend will not be affected greatly if the land use remains unchanged from the present conditions. However, if large levels of deforestation occur in the future, the increase in the sedimentation rate would have a dramatic effect on the sustainability of the Mangla Reservoir.