Coastal resources, livelihoods and the 2004 Indian Ocean tsunami in Aceh, Indonesia

Abstract

The 2004 Indian Ocean tsunami drastically altered the coastal zone of Aceh, Indonesia. Tsunami induced erosion of the coast, including aquaculture farms (tambak) and mangrove forests, destroyed livelihood opportunities and access to coastal resources. The following paper discusses impacts of the tsunami on coastal resources and the associated coastal and disaster management implications. Data is drawn from a time series of digitised mean high water marks (MHWM's) sourced from Google Earth imagery, along with areal measurements of tambak, mangrove and casuarina cover and qualitative interviews with local residents. Two sites, namely, the Banda Aceh west coast and Lhok Nga Bay were studied. The results reveal that within these study sites 68% of mangroves and 92% of tambak ponds have not recovered since the tsunami resulting in the loss of between 241 and 725 tambak livelihoods and mangrove supplied resources including food, wood and shelter. Unique coastal environments respond to, and recover from, tsunami differently depending on factors such as tsunami characteristics, wave climate, sediment supply, vegetation, morphology and level of pre-disturbance human modification. While the study supports recent findings that mangrove and casuarina forests do not substantially mitigate the impact of large tsunamis, it strongly encourages their conservation for the environmental and economic sustainability of coastal communities. The study recommends that better integrated management of coastal resources such as mangroves and tambak, considering disaster management, environmental and economic concerns, will strengthen the resiliency of vulnerable coastal communities such as those in Aceh to future disaster.