Marine lakes in Indonesia: Understanding shifts in biodiversity and food webs in tropical coastal ecosystems under increasing water temperature and terrestrial influence

Summary

A major challenge in marine ecology is understanding how tropical coastal ecosystems will respond to increasing seawater temperature and high terrestrial input. I used marine lakes, small landlocked bodies of marine water, as model systems to study these impacts, as they represent natural settings for these predicted environmental scenarios. This doctoral thesis investigates the potential impacts of the stressors on the biological diversity, benthic community structure, and food web dynamics of coastal ecosystems in Raja Ampat, Southwest Papua, Indonesia. I found that marine lakes with higher temperatures and terrestrial input harbor lower coral cover and instead show benthic dominance of various non-coral groups. This shift can reduce biodiversity, disrupt species interactions, and lead to less complex food web structures. If we can extrapolate the scenarios of marine lakes to other coastal tropical ecosystems, lower diversity and resilience could affect fisheries, coastal protection, and other ecosystem services.