A kelp forest is one of the most ecologically dynamic and biologically diverse habitats on the planet. Primary production in a kelp forest is amongst the highest in all aquatic ecosystems.
The term kelp refers to marine algae belonging to the order Laminariales. Kelp is categorized as a large brown seaweed.
A kelp “plant” (technically called a “thallus”) is made up of three parts. The holdfast acts like a root in that it anchors the kelp plant to the sea floor although it does not deliver any nutrients. The stipe is similar to a plant stalk, extending vertically from the holdfast to support the fronds. The fronds are like long leaves that grow from the end of the stipe, absorbing nutrients and providing a site for photosynthesis.
Although the stipe stands strongly vertical underwater, the fronds naturally hang downwards and move freely from side-to-side with the action of the water currents. A kelp “plant” can regrow if its fronds are cut, but not if its stipe is cut. Kelp reproduces by the production of spores during the winter.
Kelp is a key contributor to reducing the CO2 in our atmosphere as it absorbs five times more carbon than plants on land.
When kelp absorbs carbon, it reduces ocean acidity which is a by-product of the excess CO2 in our atmosphere. Ocean acidification is disastrous for shellfish such as mussels as it can inhibit shell growth.
Storm Surges and Wave Damage:
Climate change is predicted to increase storm surges and wave heights. Kelp offers a first line of defence by taking the brunt impact of wave action instead of the coastline. As well, kelp forests trap sediment, reducing the amount of ground lost through coastal erosion.
With the warmer waters caused by climate change along with increased nitrogen run-off from agricultural grounds, a rapid increase of algae populations can occur. Known as “red tides” or “algae blooms”, these produce neurotoxins that can be harmful by direct skin contact and can also contaminate seafood. Kelp forests protect against these occurrences by absorbing excess nitrogen from agricultural run-off.