What Is Algae?
Algae are entities that are widespread all throughout the world. They are growing in various sizes, shapes, and colors. They may live alone or they may grow on other organisms’ surfaces, on rocks or in the soil. Such species are critical as they make a lot of the oxygen on Earth that animals and humans require for breathing. A few of these entities such as seaweed resemble plants. In fact, they are neither animals nor plants. Rather, they belong to a class of living entities known as protists. These highly differ in size and are increasing in many different ecosystems. Microscopic algae in oceans and lakes, or phytoplankton, float or dive. Phytoplankton is so tiny that one thousand of them could be accommodated on a pin’s head. The largest species of algae are coral and can range from the bottom of the ocean to the surface of the water up to 100 m (300 ft).
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Though most of the species thrive in seawater or freshwater, they do grow in soil, plants, and animals like tortoises and polar bears, and in or below porous rocks such as sandstone and calcareous. They can withstand an extensive range of temperatures and can expand deep inside the polar ice in hot springs, on snowbanks.
There are numerous groups of living organisms in the algae (singular algae). These are habitually found in moist environments or water bodies and by photosynthesis absorbing light energy, turning inorganic substances with the absorbed energy into simple sugars. Almost all algae have photosynthesizing parts. In contrast to other photosynthetic bacteria such as green and purple bacteria, they produce oxygen. Some one-celled algae completely depend on external energy sources and their photosynthetic apparatus has been either lost or reduced.
Importance of Algae
As a Source of Oxygen
It is responsible for producing more than 30% of the oxygen due to a large amount of algae in the ecosystem that land animals rely on for their life. Some figures suggest that approximately 50% of what terrestrial animals need is the amount of oxygen provided by the algae. If the algae die off as a result of mineral degradation in the water, the decomposition and subsequent decrease in the production of oxygen may result in the fish’s death.
As a Source of Food
Algae occupy the producer’s position within a food chain, meaning that many food chains start with them. They are extremely important because a large number of aquatic animals ranging from tadpoles to fish species like catfish and Siamese algae eater are a food source. Life in the ocean is heavily dependent on algae because larger species consume the creatures that prey on algae to guarantee that life in the sea persists.
As an Indicator of Pollution
Algae can also show what kinds of contaminants a water body absorbs when specific pollutants affect its production. Farm chemicals, particularly fertilizers, have a large concentration of chemicals such as phosphorus and nitrogen that contribute to the algae’s rapid growth. Other pollutants contain a high level of heavy metals that can inhibit the plant’s growth if taken up by the algae in sufficient quantities.
As a Provision of Habitat
Large algae species encourage aquatic life to grow and spread as they provide habitats for multiple species. Kelp forests are examples of large algae ecosystems that provide most animals with shelter. It is often possible to find more than one kelp species within a single kelp forest. In kelp forests, animals may include nudibranchs, snails, skeleton shrimps, and sea urchins, among others.
Also Read: What is Blue Green Algae?
What is an Algae bloom?
An algal bloom or algae bloom is a rapid increase or aggregation in the algae population of freshwater or marine water systems and is often identified by water discolouration of their pigments. The term algae encompass most types of aquatic photosynthetic organisms, including macroscopic, multicellular organisms such as seaweed and small, single-celled organisms such as cyanobacteria. A kelp forest is an example of a macroscopic blooming algal.
Algal blooms are the result of a nutrient, such as fertilizer runoff nitrogen or phosphorus, entering the water environment and causing excessive algae growth. An algal bloom affects the entire ecosystem; it can yield beneficial outcomes, such as simply feeding higher tropical levels to more harmful effects, preventing sunshine from entering other species, inducing oxygen loss in the atmosphere, and secreting toxins into the environment depending on the individual. The process of nutrient oversupply leading to the growth of algae and depletion of oxygen is called eutrophication.
What Are The Causes of Algae Bloom?
1. Excess of Nutrients
Algal proliferation is caused mostly by the accumulation in the water of large quantities of phosphorus and nitrogen. These minerals were wiped away from fields and farmland where nitrogen and phosphatic fertilizers are deeply contaminated with. Rains are instrumental in wiping away these leachable nutrients from the soil into water bodies like streams and rivers that gradually end up in large ponds like oceans.
Such nutrients are also collected via drainage systems into waterways. Untreated, raw sewage finds its way into water bodies due to poor sewage treatment and because it is rich in nitrogen compounds like ammonia and nitrates, it leads to algal bloom.
Water pollution, in particular, the leakage into rivers of crudely treated or untreated industrial waste contributes to the introduction of pure toxic waste into water systems and as it contains contaminants and substances such as lead, nitrogen, and phosphorus; the result is heavy growth of algae.
2. Presence of Dead Organic Matter
There are generally many types of bacteria present both in the atmosphere and in water. They are all looking for suitable growth and nutrition media. So, like other bacteria, by the inclusion of dead species in water, the algae bacterium is activated. The dead organic matter, together with the nutrients in the water, ends up propagating the growth of algae in water leading to the blooming of algae.
3. High Temperatures
The world faces the depletion of the ozone layer caused by global warming. This is one of the main reasons why algal bloom is fast-growing. For certain bacteria to live both in and out of the water, a favourable temperature is needed.
The excessively high temperatures encountered as a result of global warming have resulted in the accelerated decomposition of nutrients such as nitrates and ammonia, which are simpler ways to use and expand in quantity for bacteria.
4. Slow Moving Water
Algal blooms require huge quantities of water that are nearly yet to grow. Their proliferation in these waters is less troubling and this explains their confined growth in fast-flowing streams and rivers.
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