This is because ecosystem services are dependent on one another and exhibit complex interactions that generate trade-offs in the delivery of one ecosystem service relative to the delivery of others. For the ocean economy, this is relevant because these interactions determine indirectly the viability of ocean-based industries. By way of illustration: coastal run-off and eutrophication, acidification through increasing greenhouse gas (GHG) emissions, and poor water quality through pollution lead to changes in fish migration patterns and even extinction of fish stocks. All are examples of how human activity indirectly intervenes in the functioning of marine ecosystems, thereby undermining the economic viability of the ocean economy .