Editing Great Barrier Reef (section)

====Eutrophication====
Farming fertiliser runoff release [[nitrogen]], [[phosphorus]], and [[potassium]] into the oceanic ecosystem, and these [[limiting nutrient]]s cause massive algal growth which eventually leads to a reduction in oxygen available for other creatures in a process called [[eutrophication]]. This decreases the biodiversity in the affected areas, altering the [[species composition]]. A study by Katharina Fabricius and Glen Death of [[Australian Institute of Marine Science]] found that hard corals numbers were almost double on reefs that were far from agricultural areas.<ref name="Human Impact on the Great Barrier Reef"/>

Fertilizers also increase the amount of phytoplankton available for the crown-of-thorns starfish larvae to consume. A study showed that a doubling of the chlorophyll in the water leads to a tenfold increase in the crown-of-thorns starfish larvae's survival rate.<ref name="Human Impact on the Great Barrier Reef"/>