摘要：Debris flows triggered by Merapi eruption in 2010 have impacts on the environment and social condition along the rivers on the volcano, especially in Pabelan River. Material resulted from debris flows could change on morphology and porosity of riverbed surface material, as well as the capacity of sediment. Therefore, it is important to study the influence of Merapi eruption in 2010 on environmental and social conditions in Pabelan River. To determine the river morphology was used Ronsgen method. To calculate porosity of riverbed surface material was used the equation was proposed by Sulaiman. Einstein equation was used to calculate sediment transport. To investigate the social conditions, damage land and sand mining activity were used as parameters. The result has shown that morphology types at confluence Progo-Pabelan Rivers, Srowol Bridge, and Pabelan Bridge 1 were D5b, D5b and E5, respectively. Sedimentation has occurred in the segment between the confluence of Progo-Pabelan Rivers and Srowol Bridge. Erosion has taken place in the segment between Srowol Bridge and Pabelan Bridge 1. The riverbank collapses took place along the river and it gave a negative impact on social conditions. The sand mining activity was intensive, and the activity has a positive impact on the economical inhabitants.
关键词：the 2010 Merapi eruption;environment;social condition;Pabelan River
