Kelp is a heterokont, or a group of protists, most of which are algae. It is multicellular and is some of the largest. Most kelp species are made up of a thallus, or body, that has blades or leaf-like structures. These are flat and orientate from stems or stipes. These stripes look like traditional plant stems but aren’t. They mainly provide support to the blades.
It attaches itself to the ocean floor, a rock, or another hard surface through the use of the holdfast, or a root-like structure that emerges from the base of the kelp. Some kelp species, such as American species, also have gas-filled bladders that keep the fronds afloat in the water, allowing this to create its distinctive forest-like structure.
Kelp Habitat
It grows in what is commonly referred to as kelp forests. These appear in shallow oceans, dating back 5 to 23 million years ago to the Miocene. It needs water temperatures to be six and fourteen degrees Celsius or forty-three and fifty-seven degrees Fahrenheit. They grow best in cold water filled with nutrients. It relies on the sun for nutrients, meaning that they are always found along the coast, requiring clear water to thrive. The clearer the water, the more easily the sun makes it under the water’s surface.
While it can be found worldwide, the majority grows along the shoreline of the Pacific coast, from Alaska to the south of California.
Kelp Growth and Reproduction
Kelp begins growing at the base of the meristem, a part of the plant that consists of undifferentiated cells capable of cell division. Or, more simply, the place where the blades meet the stem, the part of the plant that looks like the stem (although it works differently). Some species of this can reach up to 150 feet or forty-five meters tall. This means that the forests, which are discussed in more detail below, can quickly overtake an area of the ocean floor.
The largest kelp species can live for up to seven years, growing around 10 inches or 27 centimeters a day in the spring. In ideal conditions, it might grow up to two feet or 61 centimeters in one day.
Its growth begins when, in the haploid stage, the mature kelp releases spores and they germinate. These become either male or female. In what is known as the diploid sporophyte stage, sexual reproduction begins. The largest species of this can live for up to seven years.
Kelp Forests
Kelp forests are sometimes compared to coral reefs and mangrove forests, although the systems do not overlap. They all provide similar underwater habitats for hundreds or even thousands of species. These include other algae, fish, and invertebrates. Other creatures, like marine mammals and birds, utilize its forests as sources of food. Some of the most commonly found invertebrates are prawns, snails, and brittle stars. Some of these species spend their whole lives in kelp forests, living, breeding, and dying there. At the same time, others use them only as a nursery, a place that provides increased protection for their young while they are most vulnerable.
Predators are well aware of the relative safety of its forests and are often spotted hunting along open spaces between the kelp.
In contrast to coral reefs and mangrove forests, these forests are less permanent. They live, die, and reappear with ease with shifts in their population sizes and the presence of herbivores. Other elements that impact its growth include the warmth of the water, the pattern of currents, and how many nutrients the forest receives. Storms are also a threat to its populations, with the potential to destroy or significantly weaken entire forests.
Importance of Kelp Forests
Kelp forests support a greater variety and higher diversity of plants and animals than nearly any other ocean community. Many organisms use the thick blades as a safe shelter for their young, protecting them from predators and even rough storms. These underwater towers offer food, shelter, and protection for a wide range of marine life, including seals, sea lions, sea otters, invertebrates, fish, whales, birds, and more. The forests offer various ecosystem services to humans and provide habitat for several commercially important fishery species, including its bass and black .
Guardians of Marine Biodiversity
Kelp forests, found along much of the west coast of North America, are vital marine ecosystems composed of large brown algae thriving in cool, shallow waters near the shore. These dense underwater forests provide crucial food and shelter for a diverse array of marine life, including thousands of fish, invertebrates, and mammals. The rich biodiversity in forests surpasses that of nearly any other ocean community. The forests flourish in cold, nutrient-rich waters and typically grow in shallow areas, where they can access ample light for photosynthesis. NOAA scientists continuously monitor these ecosystems to track changes and understand the factors influencing their health, whether natural or human-induced.
Kelp Uses
Kelp has numerous uses. Some of these include being used as a binding agent in products like shampoo, toothpaste, and ranch dressing. They can also be found in cakes, dairy products, and frozen food, as well as pharmaceuticals. Specifically, it’s the Algin in Kelp that’s useful to commercial companies. It can be extracted and used to meet various ends. Hundreds of thousands of tons are harvested just around California every year.
It’s also possible to buy kelp as its own product at health food stores. It contains vitamin K and calcium, as well as very few calories. The farming is another related industry, bringing in billions of dollars a year (as it is connected to the broader seaweed-farming industry). One farm can produce 40 metric tons a year.
Nutritional Benefits
Kelp, a nutrient-dense seaweed, absorbs a wide range of essential vitamins, minerals, and trace elements from its surrounding marine environment. Among its many benefits, it is recognized as one of the best natural sources of iodine, a crucial element for thyroid hormone production. Adequate iodine intake is essential for maintaining a healthy metabolism, preventing the enlargement of the thyroid gland, and promoting overall thyroid function.
Beyond its role in thyroid health, it also offers a host of other health benefits. It is rich in various vitamins and minerals, including Vitamin K1, folate, magnesium, iron, Vitamin A, pantothenic acid, and calcium. These nutrients contribute to bone health, support cell division, and enhance overall well-being. For instance, Vitamin K1 and calcium are vital for maintaining strong bones, while folate is necessary for healthy cell division and growth.
However, it’s important to consume in moderation. While iodine is beneficial in the right amounts, excessive iodine intake, especially from supplements or excessive consumption of it, can lead to thyroid problems. Therefore, it’s essential to balance consumption within a diet to maximize its health benefits without risking potential adverse effects.
Disease-fighting properties
Inflammation and stress are recognized as risk factors for various chronic diseases, but incorporating antioxidant-rich foods into the diet may help mitigate these risks. It is abundant in antioxidants like carotenoids and flavonoids, can combat disease-causing free radicals. Additionally, antioxidant minerals such as manganese and zinc play a role in reducing oxidative stress, potentially protecting cardiovascular health and lowering cancer risk.
Recent research has examined the potential benefits of sea vegetables in relation to estrogen-related and colon cancers, osteoarthritis, and other conditions. Findings suggest that kelp might help slow the progression of colon and breast cancers. Studies on isolated cells have also indicated that fucoidan may help prevent the spread of lung and prostate cancer.
Despite these promising results, there is no strong evidence yet that it can significantly reduce cancer risk in individuals.
Conservation
In addition to the natural threats to its populations, such as herbivores and currents, human-caused effects are also detrimental. Fishing practices, pollution, and destruction caused by boats getting tangled in forests are other reasons why kelp forests become depleted.
It’s important while moving forward with conservation efforts to ensure that protected ocean areas are maintained and expanded. In the last years, rising ocean temperatures have destroyed many miles of kelp forests around the world. According to a Science study, Australia has lost more than 60 miles of forest, which is among the largest and fastest losses ever observed.
Facts about Kelp
- Kelp are not plants. They are very large brown algae.
- Some species can grow to 150 feet in ideal conditions.
- Kelp forests help to create diverse ecosystems on the ocean floor.
- Kelp lives in coastal areas and prefers cold water.
- Kelp can be harvested to use as a binding agent in everything from toothpaste to cereal.
- Kelp forests are found around the world.
- They use something called holdfasts to attach to structures like rocks.
- Kelp have gas-filled bladders or pneumatocysts to help keep the fronds floating in the water.
- Sea urchins are dangerous when introduced to kelp populations. They can quickly decimate populations if not curtailed.
- Storms like El Niño are detrimental to kelp forests.
