Global warming and human-induced changes in megafauna and invasive species abundances are threatening marine and terrestrial ecosystems. These impacts can alter the local ecological equilibrium by shifting plant-herbivore and other ecological interactions. Seagrasses are marine plants that provide vital ecosystem services such as carbon storage and coastal protection. I will study how seagrass ecosystems respond to important stressors, by investigating their resilience and ecosystem service provisioning under pressure of e.g. turtle grazing and invasive species expansion. The aim is to provide timely management advice in order to predict and prevent future collapse of valuable seagrass ecosystems.