Final answer:
Eutrophication is the process where excessive nutrients in aquatic ecosystems lead to algae overgrowth and oxygen depletion, and it is exacerbated by the use of artificial fertilizers and burning of fossil fuels which alters both the nitrogen and carbon cycles, contributing to climate change.
Step-by-step explanation:
By increasing our use of fossil fuels, humans contribute to the process of eutrophication. This biological term refers to the accumulation of nutrients, particularly nitrogen and phosphorus, in aquatic ecosystems, which can lead to an overgrowth of algae, causing deleterious effects such as oxygen depletion and reduced water quality. The overuse of artificial fertilizers in agriculture leads to runoff containing these key nutrients into our waterways. Moreover, the combustion of fossil fuels releases various nitrogen oxides into the atmosphere, which also impact the nitrogen cycle and contribute to both eutrophication and the broader issue of climate change.
The burning of fossil fuels also impacts the carbon cycle, increasing atmospheric CO₂ and therefore exacerbating the greenhouse effect. This further contributes to global warming, which can indirectly affect eutrophication by affecting temperature-dependent processes within aquatic ecosystems. Hence, our energy policies and practices have a significant impact on both the global climate and localized aquatic environments.