Assessing habitat risk to support marine spatial planning in Indramayu’s Coastal Zone, Indonesia

Abstract An ecosystem-based approach in spatial planning can provide valuable insight for assessing the benefits obtained from various space zoning. Spatial planning in coastal areas needs to be carried out comprehensively by understanding the impacts of human activities on coastal habitats. This study examined the risks posed to mangrove habitats in the Indramayu coastal area, West Java Province, Indonesia by stressors stemming from aquaculture, agriculture, and settlements. We employed the Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST), Habitat Risk Assessment model to assess locations where mangrove habitats are at high risk and to identify the contributing stressors. We analyzed the current distribution of habitats and coastal activities and developed three scenarios for zoning these activities in the future. The results showed that habitat risk values varied across the five sub-districts in Indramayu. The analysis indicates that high-risk levels are most associated with low mangrove densities, with aquaculture identified as the primary stressor impacting high-risk levels. Intensive intervention is required to address aquaculture stressors, while low-intensity intervention is sufficient for agriculture and settlement stressors. Based on scenario analysis, the inclusion of potential mangrove areas in both scenarios demonstrated an apparent reduction in the habitat's risk levels to stressors compared to the baseline. These results expand our knowledge to understand how the stressors impact the mangrove habitat under current and future management scenarios. Furthermore, the study provides insight for coastal planners to plan development activities that will minimize pressure on mangrove habitats.