Management of mangrove ecosystems for increasing fisheries production in Lubuk Kertang village, North Sumatra, Indonesia

Mangroves play an important and valuable role in coastal and marine ecosystems, in particular acting as nursery grounds for coastal and offshore fisheries. Mangrove ecosystems in North Sumatra, Indonesia, have been lost through anthropogenic activities. The purpose of this study was to calculate the potential contribution of mangrove litter to fisheries and to design a dynamic model of mangrove management for optimal and sustainable fisheries utilisation using Powersim Software. This study used observations (mangrove characteristics including litter production and environmental parameters) and interviews (benefit values) to consider the link between mangrove area and fishery resources. The collected data were entered into the dynamic model, and scenarios were simulated for up to 75 years. Results showed that the estimated potential fisheries benefits amount to 1,202.282 kg ha-1 year-1 or IDR 22,663,023 (US$ 1,679) ha-1 year-1. An increase in mangrove area of up to 10 ha year-1 is a minimum requirement for sustainable utilisation of fisheries. The species composition providing maximum value for coastal fisheries consisted of Avicennia spp. 15.2%, Rhizophora spp. 60.8% and Sonneratia spp. 24%.