Assessing the interconnected effects of policy interventions on shrimp farming expansion and mangrove ecosystems through system dynamics

Abstract

Since the early 2000s, Ca Mau has experienced a rapid boom in shrimp farming, leading to the conversion of mangroves into shrimp ponds and impeding mangrove forest conservation. Despite its negative environmental impacts, shrimp aquaculture remains vital to Ca Mau’s economy by providing employment opportunities and contributing to the province’s gross domestic product. This study constructed a system dynamic model to analyze the complex system of shrimp aquaculture and mangrove forests under two development scenarios: the Business-as-Usual (BAU) scenario and the Policy scenario. In the BAU scenario, shrimp aquaculture will continue to expand, resulting in the conversion of more mangroves into ponds and a decrease in Ca Mau’s mangrove forest to 70,349 (± 888.801) hectares in 2050. However, this expansion will bolster rural employment and the province’s economy, generating 14,250 (± 0.336) billion VND (US$ 570 million) in 2050. Conversely, in the Policy scenario, stabilizing shrimp areas at 280,000 hectares as a policy target will regulate mangrove conversion, allowing mangroves to regenerate (77,016 (± 687.155) hectares in 2050) and enhancing carbon storage (65 × 106 (± 0.58 × 106) MgC in 2050). However, challenges arise in the Policy scenario concerning potential economic stagnation, conflicts with other development priorities, and rural job losses. Officials must consider more than just the area of shrimp ponds to achieve sustainable development. Effective land use strategies should be implemented to ensure equilibrium between shrimp aquaculture and mangroves. Diversifying economic activities and promoting alternative livelihoods can mitigate the dependence on shrimp farming and offset the effects of policy interventions.