Nutrient Requirements of Caulerpa Seaweed

Admired for its ability to gain hold where other species cannot and admonished for its tendency to blot out its seaweed kin, Caulerpa seaweed is clearly no ordinary kelp. Whereas most seaweeds obtain the bulk of their nutrients from organisms swishing about the water column around them, Caulerpa seaweed is able to absorb nutrients from the the seafloor as well. It grows mainly in warmer saltwater areas, but beyond that its nutrient requirements can be extremely low, giving Caulerpa the ability to adapt to just about any marine environment.

Features

Whether Caulerpa seaweed is a nuisance or a boon is up for debate, but there is no questioning its potential to grow and thrive. This strain of seaweed is known to be a beautiful yet tyrannic addition to the marine areas it haunts, often invading turf of other native seaweeds and taking it for its own. It is able to absorb nutrients in ways other seaweeds cannot, giving it an advantage that it often exploits by growing in thick blankets, pinching out competing seaweeds along the way.

Warning

Caulerpa seaweed is unpopular in some areas because of its invasive tendencies. Its ability to absorb nutrients more efficiently makes some species of Caulerpa an ultra invasive predator when it finds its way into foreign seas. After its arrival it often does not take more than a few years for local species to be wiped out. Major efforts are now being made worldwide to monitor seaweed beds and action plans are in place to combat invasive Caulerpa at first sight.

Function

Some species of Caulerpa require very specific nutrition and light exposure to proliferate, others are much more generalized species that can grow in a wide variety of habitats. The common thread is that all species usually send branches with leaflike structures upward and rhyzoidal rootlike structures downward. The rhyzoids have the potential to anchor in the seabed and extract nutrients while the branches have the ability to photosynthesize solar energy from closer to the surface.

Considerations

In other areas, species of Caulerpa seaweed are taking over in an entirely different manner. In marine areas that are becoming polluted, they are moving in after native species are decimated. One of the first effects of most pollution is that the seawater becomes clouded, usually by excess nutrients. While many native seaweeds perish in these conditions because of the lack of sunlight, if species like Caulerpa taxiflora are introduced, they can thrive because of their highly adaptive nature.

Potential

This adaptable seaweed with low nutrient requirements does have some positive attributes, such as if you are trying to grow the species whereas these traits are quite attractive. Caulerpa species have been a popular food for centuries for Japanese, Indonesians, Filipinos and Polynesians. More recently it has been used in the aquarium industry for its ability to produce beautiful fronds in underwater environments where other seaweeds wither.

References

• National management plan for genus Caulerpa