What are the effects of fertiliser runoff into the Great Barrier Reef World Heritage Area?
Nutrient input loads to the inshore area of the Great Barrier Reef World Heritage Area have risen by more than 30% following catchment development. The two principal nutrients, nitrogen and phosphorus, exist in several forms in marine waters. When there is a large concentration of nutrients (phosphorus and nitrogen) in the water, the Reef is affected in a number of ways: • Nutrients encourage phytoplankton growth, which leads to decreased water clarity and reduced light for coral and seagrass communities to grow. • Phytoplankton growth encourages filter-feeding organisms such as sponges, tubeworms and barnacles to grow, which compete for space with the existing coral community. • Nutrients encourage algal growth, which grow over coral communities. • Excessive phosphorus weakens the coral skeleton, making it vulnerable to storm damage. For further information on the effects of fertiliser take a look at the Great Barrier Reef Water Quality: Current Issues report and Research Publication
