Algal Bloom

Algae are organisms that can be found all over the earth. They come in a variety of sizes, shapes, and colours. They can survive on their own or grow on the surfaces of other organisms, rocks, or dirt. These species are important because they produce much of the oxygen that animals and humans need to breathe. Some of these organisms, such as seaweed, have a plant-like appearance. They are neither animals nor plants, in truth. Rather, they are protists, which are a type of living organism. These come in a wide range of sizes and are becoming more common in a variety of environments. Phytoplankton, or microscopic algae found in oceans and lakes, floats or dives. Phytoplankton is so little that a thousand of them might fit on the head of a pin. Coral algae are the largest algae species, with a range of up to 100 metres from the ocean’s bottom to the water’s surface (300 ft).

Though most of the species are found in seawater or freshwater, they can also be found in soil, vegetation, and animals like tortoises and polar bears, as well as in or beneath porous rocks like sandstone and limestone. They can endure a wide range of temperatures and expand deep within arctic ice in hot springs and on snowbanks.

Algae has a diverse range of living species (singular algae). These are commonly found in wet areas or near water bodies, and they work by absorbing light energy and converting inorganic compounds into simple sugars. Photosynthetic components can be found in almost all algae. They create oxygen, unlike other photosynthetic bacteria like green and purple bacteria. Some one-celled algae rely entirely on external energy sources, and their photosynthetic system has been lost or severely degraded.

Algae’s Importance

As an Oxygen Source

Algae are responsible for more than 30% of overall photosynthetic oxygen production. According to some estimates, algae contributes about half of a terrestrial animal’s oxygen requirement. Mineral depletion in water may result in a reduction in algal population, resulting in fish death due to oxygen deprivation.

As a Source of Food

Algae are the principal producers of food. They are critical because a significant variety of aquatic animals rely largely on algae for their nourishment.

As a Pollution Indicator

Algae growth is a sign that there are toxins in the water. The rapid growth of algae in water bodies is caused by an increase in mineral content caused by agricultural pesticides and fertilisers that are high in nitrogen and phosphorus. Heavy metals impede plant growth when consumed in large quantities by algae.

As a Habitat Provision

Many other organisms use large algal species as habitat. Kelp forests, for example, are huge algal ecosystems that provide habitat for a variety of species such as snails, shrimp, and sea urchins. In a kelp forest, there may be multiple species of kelp.

What is an Algal Bloom, exactly?

An algal bloom, also known as an algae bloom, is a fast rise or aggregation of algae in freshwater or marine water systems, which is commonly characterised by water discoloration of their colours. Algae refers to a wide range of aquatic photosynthetic creatures, including large, multicellular animals like seaweed and microscopic, single-celled organisms like cyanobacteria. A macroscopic blooming algal is an example of a kelp forest.

Algal blooms occur when a nutrient, such as nitrogen or phosphorus from fertiliser runoff, enters the water environment and causes excessive algae growth. An algal bloom has a wide range of consequences on the ecosystem, from simply feeding greater tropical levels to more detrimental effects like blocking sunlight from reaching other species, causing oxygen loss in the atmosphere, and secreting poisons into the environment, depending on the individual. Eutrophication is the process of nutrient overstock resulting in the growth of algae and oxygen deprivation.

Red Algae

Red algae are classified as Rhodophyta and are members of the Rhodophyceae class. The Florideophyceae & Bangiophyceae families of red algae are divided into two groups. In both marine and freshwater settings, the Florideophyceae and Bangiophyceae families account for 99 percent of red algal diversity.

Red algae, also known as Rhodophyta, are the oldest form of the eukaryotic algae and may be found predominantly in freshwater lakes. phycocyanin chlorophyll A, and phycoerythrin, among other pigments, give them their red colour. Only Aneurianna & Lenormandia Sonder have foliar blades, making them members of the Amansieae tribe (Rhodomelaceae, Ceramiales, Rhodophyta). They are a unique species that can be found predominantly in deep freshwater bodies.

Causes of Algae Bloom and its Prevention

1. Nutrient Overabundance

The accumulation of significant amounts of phosphate and nitrogen in the water is the primary cause of algal proliferation. These minerals were washed away from fields and farmland that had been heavily contaminated with nitrogen and phosphatic fertilisers. Rains play an important role in removing these leachable nutrients from the soil and transporting them to water bodies such as streams and rivers, where they eventually end up in enormous ponds like oceans.

Such fertilisers are also collected and discharged into waterways via drainage systems. Because it is rich in nitrogen compounds like ammonia and nitrates, untreated, raw sewage makes its way into water bodies due to poor sewage treatment, resulting in an algal bloom.

Water pollution, particularly the discharge of crudely treated or untreated industrial waste into rivers, contributes to the entry of pure toxic waste into water systems, which comprises pollutants and compounds such as lead, nitrogen, and phosphorus, resulting in heavy algae development.

2. The presence of organic matter that has died

Bacteria can be found in large numbers in both the atmosphere and the ocean. They’re all looking for the right medium for growth and sustenance. As with other bacteria, the algal bacterium is activated by the presence of dead species in water. The dead organic debris, combined with the nutrients in the water, promotes the growth of algae in the water, resulting in algal blooming.

3. Extreme Temperatures

The ozone layer is being depleted as a result of global warming. This is one of the primary causes for the rapid growth of algal blooms. A suitable temperature is required for certain bacteria to survive both in and out of the water.

Excessively high temperatures as a result of global warming have expedited the degradation of nutrients such as nitrates and ammonia, which are easier for bacteria to use and expand in amount.

4. Water That Moves Slowly

Algal blooms necessitate massive amounts of water that have yet to mature. Their spread in these waterways is less concerning, which is why they are restricted to fast-flowing streams and rivers.

Conclusion

An algal bloom is a fast rise or aggregation in the algae population in freshwater or marine water systems. Because of the algae’s colouring, water discoloration is a common symptom. Rather than macroscopic algae, the word “algal bloom” usually refers to the fast multiplication of tiny algae.

Excessive nutrient aggregation, such as phosphate or nitrogen, is the primary cause of algal bloom. Dead organic materials, in combination with nutrients in the water, can sometimes promote the growth of algae in the water, resulting in algae blooming.

A harmful algal bloom (HAB) is an algal bloom that negatively impacts other organisms by toxin production, mechanical damage, or other mechanisms. The HABs’ diversity makes management difficult, especially in vulnerable coastal areas.  HABs have been linked to large-scale marine mortality and shellfish poisonings.  HABs are closely watched due to their detrimental economic and health repercussions. 

Humans are at risk from HAB. Humans can be exposed to toxic algae through eating contaminated seafood, swimming or other water activities, or breathing toxins in the air.

The water may become discoloured or muddy, ranging in colour from purple to almost pink, generally red or green. Not all algal blooms create water discoloration.