Eutrophication is the enrichment of an ecosystem (typically aquatic) with chemical nutrients (nitrates, phosphates, etc.)
- The nutrients can be introduced via leaching from soil by rainfall or released as part of sewage
- Eutrophication is common around agricultural lands where the use of artificial fertilisers are prevalent
An increase in nutrient supply within waterways will result in several ecological consequences:
- A rapid growth in algal populations will occur (algal blooms) as a result of the increased availability of nutrients
- As the algae die, there will be a subsequent spike in the numbers of saprotrophic microbes (decomposers)
- The high rate of decomposition will result in an increased biochemical oxygen demand (BOD) by saprotrophic bacteria
- The saprotrophs will consume available quantities of dissolved oxygen, leading to deoxygenation of the water supply
- Eutrophication will also increase the turbidity of the water, which will reduce oxygen production by photosynthetic seaweeds
- This will stress the survival of marine organisms, potentially leading to a reduction in biodiversity within the ecosystem
Eutrophication
