Modelling the structure and functioning of an upwelling ecosystem in the Southern Taiwan Strait, China

Abstract

A first mass balance food web model was developed to parameterize and characterize the structure and functioning of the upwelling ecosystem in the Southern Taiwan Strait ( STWS ). The model representing the ecosystem state and trophic flows in 2001 includes 50 functional groups from primary producer to marine mammal and 6 fishing fleets. The basic outputs and trophic flows in the ecosystem are analyzed using ecological indicators. Results indicate that phytoplankton, zooplankton, benthos and shrimps are structuring groups while dolphins, top predatory fishes, seabirds, lizard fish, hairtail and mantis shrimps are the keystone groups within the ecosystem. Based on the maturity indicators, STWS is at a mature state. An analysis of control mechanisms indicates that the top-down effect was the primary ecosystem control mechanism, although bottom-up effect was also in play. In addition, fishing impacts were analyzed throughout the food web. Such modelling of the structure and functioning of ecosystem provides basic information for stakeholders and policy-makers to implement ecosystem-based management. • The first mass balance model in Southern Taiwan Strait (STWS) is developed. • The structure and functioning of STWS are characterized. • The top-down effect is the main mechanism of ecosystem control in STWS. • The bottom-up effect can be enhanced in the STWS due to the upwelling effect.