Systematic Analysis of the Impact of Mangrove Forest Changes on Ecosystem Services in Vietnam

Abstract

Mangroves, a form of blue carbon, encompass approximately 1,054,900 hectares globally, with Vietnam possessing 75,900 hectares, representing around 7% of the total area. Beyond providing essential resources such as food, timber, and habitat, mangroves confer diverse ecosystem services, including coastal erosion mitigation and carbon sequestration while attenuating wave energy. Nevertheless, the pervasive impacts of climate change and anthropogenic activities are precipitating a reduction in mangrove coverage, giving rise to socio-ecological challenges, including biodiversity loss, escalated carbon emissions, and heightened vulnerability to severe flooding. Efforts are underway to address this predicament; however, accurate assessment remains challenging due to the intricate nature of mangrove habitats. Survey-derived data suffers from accuracy limitations, necessitating comprehensive research utilizing satellite imagery for efficient identification within a condensed timeframe, employing a systems thinking approach to understand complex ecosystem services holistically. This research aims to detect changes in the area of mangrove forests in Vietnam using Landsat satellite imagery from 2010 to 2020, the initial implementation period of the Vietnam Forestry Development Strategy, and to analyze the impact of these changes on ecosystem services. To achieve this, high-resolution (30cm) satellite images are utilized to calculate specific vegetation indices such as NDVI, NDWI, and SAVI in QGIS software.  These indices are instrumental in detecting alterations in mangrove coverage throughout Vietnam. Additionally, this study employs systems thinking to construct a causal chain map that illustrates how changes in the mangrove area impact ecosystem services within Vietnam. Satellite imagery was harnessed for GIS analysis to evaluate the ongoing status of Vietnam's mangrove forest area over time. The alterations in the area were quantified by grid partitioning, and causal loop diagrams were utilized to comprehend how modifications in mangrove areas affect ecosystem services such as coastal protection, water purification, habitat provision, and food supply. These changes engender trade-offs. This study is significant as it utilizes high-resolution satellite data to quantify the change in Vietnam's mangrove forest area over time. It also underscores the impact of these changes on ecosystem services from a systems-thinking perspective. Moreover, deducing the ecosystem service structure of mangrove forests from causal chain maps can serve as a cornerstone for formulating policies aimed at safeguarding mangrove forests for decision-makers in Vietnam and other countries with similar ecosystems. Additionally, exploring the potential of mangroves as blue carbon sources can contribute significantly to carbon neutrality and planning. Acknowldegemt This research was supported by "Development of living shoreline technology based on blue carbon science toward climate change adaptation" of Korea Institute of Marine Science & Technology Promotion (KIMST) funded by the Ministry of Oceans and Fisheries (KIMST-20220526)