Nutrient cycle

Just as there is a nutrient cycle on land, there is also one in the ocean. Put simply, this involves the continuous movement of essential substances, such as nitrogen and phosphorus, through water, living organisms and, to a certain extent, the seabed. Tiny algae (phytoplankton) on the surface of the ocean use the nutrients in the water to carry out photosynthesis. These algae form the basis of almost all life in the ocean. When they are eaten or die, the organic material sinks to the depths. Bacteria then decompose these remains, releasing the nutrients again. Eventually, ocean currents and upwelling areas bring the nutrients back to the surface, and the cycle begins again. Without this invisible recycling process, there would be hardly any life in the ocean. However, problems can arise when there are too many nutrients in the water. This can upset the balance of the ecosystem.

More on nutrients in the ocean