What is Kelp? Kelp is a type of large, brown seaweed that grows in abundance in cool, coastal waters. Although kelp undergoes photosynthesis to produce energy, it is not to be mistaken for a plant. Instead, it is considered a marine algae. As an algae, kelp provides habitat, food, and shelter to countless biodiverse ecosystems in the oceanic biosphere. Environmentally, they play a crucial role in carbon sequestration,  which is the process of capturing atmospheric carbon and