Socioeconomic impacts linked to land use and land use changes affecting blue carbon ecosystems in Southeast Asia: A systematic map

Land use and land use changes are the main drivers of blue carbon ecosystem (BCE) loss and degradation, which is frequently justified on the pretext of advancing economic and social development. However, there is still a lack of comprehensive investigation of the impacts of these changes on humans and communities, especially in Southeast Asia (SEA). It is also unclear how many studies have accounted for the interconnectedness of BCEs with adjacent or upstream ecosystems, as well as the potential for cascading impacts to occur across physical, chemical, and biological connections. This information is useful to ensure holistic coastal land use planning which achieves the desired outcomes of balancing environmental sustainability, economic growth, and social equity, while effectively managing risks, engaging communities, and aligning policies for long-term resilience and resource efficiency. The systematic mapping method was conducted to consolidate and synthesise the state of evidence on the research question, ‘ What is the state of evidence on the socioeconomic impacts linked to land use and land use changes affecting blue carbon ecosystems in Southeast Asia?’. A systematic map is a structured approach used to identify, categorise, assess relevant studies, and identify research gaps on a broad topic area while ensuring comprehensive coverage, transparency, and minimise bias. We conducted bibliographic searches using predefined search terms to locate relevant scientific articles. Five reviewers carried out two rounds of screening independently of each other by applying the predetermined inclusion criteria. We then systematically extracted and coded meta-data and results from the included papers, followed by analysis of the distribution and abundance of the evidence and rapid synthesis of study findings. Out of 5118 articles screened, 190 final articles were included in the database. Most of these studies are from Indonesia, followed by Vietnam, while Myanmar and Cambodia are less represented than expected, considering their significant mangrove cover. The distribution of studies by ecosystem includes 75 focused on mangroves, 2 on seagrass, 88 on non-BCEs, and 25 covering a combination of two or more ecosystems. The largest research clusters examine the impacts of aquaculture on economic living standards and the effects of urbanisation and industrialisation on general human health. Key research gaps identified include the impacts of land use and land use change on cultural and spiritual values, as well as measures of education. Research connecting land use, BCEs and socioeconomic impacts, particularly studies on indirect impacts of land use on BCEs are still limited in this region. Literature on seagrass ecosystems is notably scarce. The current evidence base points to trade-offs in land use change impacts across various socioeconomic aspects. Our systematic map highlights the complexities in resolving the interlinkages between human activities and ecosystem response and suggests ways forward towards a more informed decision-making process in managing BCEs. • Studies on socioeconomic impact were not proportionately distributed within Southeast Asia. • Major land uses affecting blue carbon ecosystems are aquaculture, urbanisation, industrialisation, and agriculture. • Research on socioeconomic impacts are focused on economic living standards, health, and material living standards. • All land use types are linked to trade-offs in impacts within and across socioeconomic categories.