Algae is a broad term that covers a wide range of plants. Alga is a generic term for sea wood. The word Alga is the singular form of the word Algae and is a Latin word. Many scientists believed that the word Algae had some connection with the Latin word Allergy, but this was met with strong opposition from other scientists because Algae has nothing to do with temperature, whereas Allergy is a type of human cold. Algae is extremely important in freshwater environments. Freshwater environments are those in which the level of salt in the water is very low, hence the name.
Algae can range from unicellular to multicellular organisms. Many studies have shown that algae lack the specialized tissues that are found in land plants. The absence of these cells could be an adaptive mechanism to the environment in which the plants will live. More than half of the world’s oxygen is produced by microscopic algae.
Phytoplankton is single-celled algae that are responsible for primary production. Because Phytoplankton is eaten by small animals at the surface levels, they are the primary producers. The larger algae provide a habitat for fish and other aquatic animals.
Types of Algae:
Algae are classified into three groups namely Red algae, Green algae, and Brown algae. Now let us understand each of these clearly:
Chlorophyceae (Green Algae): Chlorophyceae is a type of algae that belongs to the green algae class. The majority of members of this class are either fresh or salt water. Chlorophyceae contains “chlorophylls a and b”. Some of them also contain beta carotene, making Chlorophyceae unique. The shape of chloroplasts differs between green algae. Chlamydomonas resembles a cup-shaped large chloroplast, whereas Spirogyra resembles a spiral-shaped chloroplast. Few Chlorophyceae, however, have plate, griddle, or discoid shapes. Some green algae are unicellular in nature, while others are multicellular. The edges of Chlorophyceae contain cellulose and also store starch. Chlorophyceae are flexible and agile for all of these reasons.
Phaeophyceae (Brown Algae): Phaeophyceae is another type of algae that belongs to the brown algae class. The majority of Phaeophyceae are multicellular marine organisms. The brown algae thallus has a leaf-like photosynthetic part and a stalk-like structure that aids in attachment. Chlorophylls a and c, as well as xanthophylls, are found in brown algae. Fucoxanthin is also found in Phaeophyceae. Fucoxanthin is a golden brown pigment that contributes to its greenish-brown appearance. Brown algae are regarded as the most important food source as well as a habitat.
Rhodophyceae (Red Algae): Rhodophyceae is another type of algae in the red algae family. Rhodophyceae are multicellular thalli that are mostly found in the sea. Rhodophyceae also contains a few unicellular forms. Floridian starch is the primary storage food of red algae. Cell walls of Rhodophyceae contain cellulose, and the best part is that they lack flagella. Rhodophyceae are thought to be the richest source of nutritional and pharmaceutical substances.
Major similarities between Chlorophyceae, Phaeophyceae, and Rhodophyceae:
- All three belong to the kingdom Protista.
- Chlorophyceae, Phaeophyceae, and Rhodophyceae contain “chlorophyll a“.
- All three are aquatic organisms and ecologically important.
Importance of Algae Ecologically:
1. Source of Food: Algae has the best position as a producer within the food chain, which means they are present in a wide range of food chains. Life in the ocean is primarily dependent on algae because many species eat algae, which is the primary source of life in the ocean. As a result, algae is extremely important and plays a critical role in the survival of ocean life. Ecologists have demonstrated that the consumption of algae increases the lifespan of many ocean-living organisms such as fish and tadpoles. Algae are high in fibre, particularly glucan, which is essential for the human body.
Many researchers have also revealed that algae have very high nutritional values, and thus it is consumed by many people who live in coastal communities. Algae is also high in vitamins A, K, Selenium, and Magnesium, and is one of the best natural sources of Iodine. Algae is beneficial to the thyroid gland because it contains iodine, which other foods do not. As a result, as a source of food, algae is extremely important to the environment.
2. Source of Oxygen: The production of oxygen is the most important role that algae play in the environment. The presence of Chlorophyll is what distinguishes land plants from algae. This chlorophyll contributes to the formation of organic food molecules by utilizing solar and carbon dioxide energy. This process is critical for algae survival, and oxygen is released later. Algae produce more than 30% of the oxygen that land animals consume. The main reason for the world’s high level of oxygen production is the abundance of algae in the oceans. According to recent estimates, the oceans produce 50-80 per cent of the oxygen, with most of it coming from oceanic plankton, which includes plants and algae with the ability to photosynthesize. Algae may die due to mineral depletion, which may result in the death of living organisms in the oceans. As a result, algae are extremely important to the environment as a source of oxygen.
3. Indicator of Pollution: Algae plays an important role in providing information about water body pollution. There are numerous factors that cause algae to aid us in determining whether water bodies are contaminated.
One of the factors is that algae reproduce quickly, and we can examine the offspring to see if there is a difference in the rate of reproduction of algae. Many Algae have already been used as environmental indicators. The main challenge for scientists is that algae have a very short life span, making it difficult to study pollution indicators. Algae can also provide information about what types of pollutants are affecting water bodies, as different pollutants have different effects on water bodies.
Chemicals also play an important role in extending the life of algae. Farm chemicals, for example, contain a high concentration of phosphorous and nitrogen, which aid algae growth. As a result, as a source of pollution indicator, algae is crucial to the environment.
4. Indicator of Climate Change: According to the Environmental Protection Agency, carbon dioxide accounts for 76% of greenhouse gas emissions. As the algae grow, carbon dioxide is removed from the atmosphere by converting it to oxygen via the Photosynthesis process. Many studies have also shown that algae in the environment absorb a large amount of carbon dioxide, reducing the gas buildup. As a result, algae are critical to the environment as a source of climatic change indicators.
5. Provision of Habitat: Algae promotes the growth and spread of aquatic life by providing habitat for a variety of species. Forests with an abundance of brown sea wood are examples of large species of algae that provide a habitat for a variety of organisms. Kelp Forests are the name given to these types of forests. Although algae overgrowth can disrupt the ocean’s ecosystem, the spread of algae in both fresh and saltwater supports a diverse population of fish. As a result, algae is critical to the environment as a habitat.
6. Source of Fodder: Several types of livestock animals are fed on algae, particularly seaweed. For instance, Rhodymenia palmata, sometimes known as “Sheep’s weed,” is a product of algae that is used to feed animals like chickens and calves. Numerous nations, including those in northern Europe, including Sweden, Denmark, and Norway, as well as Scotland, China, New Zealand, and all of North and South America, are widely known for using algae as animal feed.
7. Pisciculture: Pisciculture, commonly referred to as fish farming, is the business of breeding and raising fish. Algae are used throughout the entire production process in fish farming, commonly known as pisciculture. According to scientists, different fish species like to eat different kinds of algae, with blue-green and green algae, as well as microalgae, serving as the most popular sources of food for fish.
The primary sources of healthful vitamins that the fish consume are floating plankton and zooplankton. Algae are also employed in fish farming as a different type of method to naturally remove carbon dioxide from the air while also supplying the water with oxygen, making the marine environment more hospitable for fish.
8. Used to Make Fertilizer: The two most prevalent types of algae utilized in the production of fertilizer are giant red algae and brown algae. Particularly, only regions close to the water use the two forms of algae (red and brown). Concentrated seaweed extract is largely used in the production of liquid fertilizer. The primary reason this sort of fertilizer is so popular is the organism’s extraordinary capacity to restore nitrogen levels that are already present in the soil. For instance, blue-green algae is often harvested and spread over agricultural fields in India where rice is grown.
Despite its many ecological benefits, algae can also be extremely harmful. Algal blooms are the overgrowth of algae in the water. These Algal blooms are extremely dangerous and can kill animals and even humans due to the toxins they release. Algal blooms also cause dead zones in the water and increase the cost of drinking water treatment. The main cause of algal blooms is sunlight and slow-moving water. Human nutrient pollution exacerbates the problem. Many different types of phytoplankton are also to blame for the harmful blooms. However, three major phytoplankton species cause illness in both animals and humans. Cyanobacteria, also known as blue-green algae, Dinoflagellates, also known as microalgae or red tide, and Diatoms are the three types.