Algae are organisms found especially in an aquatic environment , such as seas or rivers. They have the ability to photosynthesize, that is, to transform the sun’s energy into food, for this reason they grow in those areas where the rays of the sun can reach.
Although at first it could be at least curious, humans have discovered two very interesting uses: one is edible, adding them to vegetarian or vegan diets for example, and the other is as fertilizer for plants. In fact, the seaweed extract fertilizer is one of the most complete that we can give to crops. So, let’s see what these organisms are .
What are algae?
Algae are mainly aquatic organisms with photosynthetic capacity . They can be unicellular or multicellular, larger or smaller, but all of them are classified within the Eukaryota (eukaryotic) domain, since they have a true and well-defined cell nucleus.
It is believed that they began to be studied in the time of Ancient Greece , since it is known that at that time they already used the word “phykos” which translates as marine plant. “Phykos” would eventually be replaced by “fucus”, which means algae and which, in addition, gives its name to a whole genus of brown algae (Fucus) that we will see below what they are.
What are the 4 types of algae?
Algae are usually classified as follows:
- Green algae : These are usually classified as plants, as land plants are in fact believed to be descended from them. They can be unicellular or multicellular. They basically live in fresh water, although 10% of the species do so in the seas.
- Brown algae : they are protist organisms, that is, they are neither plants, nor fungi, nor animals. They are also known as brown algae. In addition, they are very important for many animals and plants, since they are primary producers of organic matter, which start a food or trophic chain.
- Red algae : also known as rhinophytes, are those that depending on their characteristics may be within the Glaucophyta kingdom if they are unicellular, or Viridiplantae, the latter being similar to Plantae (moreover, there are those who consider that Viridiplantae is not really correct, but which is simply Plantae, the kingdom of green plants).
- Other protists : this last group includes diatoms , cryptophytes, or dinoflagellates. All of them are part of the phytoplankton.
Curiosities of algae
Many algae have really curious behaviors to survive. For example, when green algae and cyanobacteria establish symbiotic relationships with fungi, they give rise to lichens . In addition, many unicellular algae live in animals, a clear example being corals, nurturing a relationship in which they can live in an environment that favors their growth.
Another curious fact is that there are certain algae that are parasitic . For example, there are some Prototheca that cause contagious mastitis in cows; or the Phormidium corallycticum , which is a cyanobacterium, which damages corals.
What is the origin of algae?
Although it is not possible to know for sure when they originated, it is believed that they did so about 1600 million years ago, during the Mesoproterozoic . Red algae would do it about 1200 million years ago, and green algae 1000 million years ago.
And for this, environmental conditions have played a very important role. For example, green algae have evolved to adapt to acidic waters, with a pH between 0.05 and 3 and with temperatures that can reach 50ºC or more; and red algae live in habitats up to 260 meters deep, where hardly any sunlight reaches.
Uses of algae
Algae have many uses, such as:
Climate change indicators
Algae are autotrophic organisms, that is, capable of making their own food through photosynthesis. But like all living things, they react in one way or another when the conditions in which they live change . For this reason, human beings help us to see the effects of global warming in the seas.
Although they not only react when the temperature rises / falls, no. Ocean acidification, caused by climate change and pollution, causes algae to proliferate . When you put fertilizers into the water, what you really do is feed the algae, which will grow so fast that they will not leave room for either the plants or the animals that live there.
This also affects fishing and therefore our diet, as there will begin to be fewer fish which will not have had the opportunity to feed properly.
Now, not everything has to be negative. There are two uses that we give to algae and that are very, very interesting, as we mentioned at the beginning. And let’s start by talking about edible algae.
Food uses
Consuming algae from time to time will help us have better health, as they have antibacterial, anti-inflammatory properties and will also help us maintain healthier skin . They are also usually included in the diets of those who suffer from hypothyroidism, as they are rich in iodine and also in fiber. But yes: do not abuse.
In Japan, for example, they have been consuming them for a long time, so their intestinal flora has been discovered to contain a bacterium that helps them digest them: Bacteroides plebeius . So unless you have direct Japanese relatives, you may have a hard time assimilating them properly.
In gardening
We come to the part that, if we grow plants, we will surely be more interested in it. Algae are used as fertilizers and as natural biostimulants . They are rich in nutrients, such as nitrogen, potassium or phosphorus, so they are a good substitute for chemical fertilizers.
In addition, depending on their presentation we have them as foliar fertilizers, that is, those that are applied directly on the leaves, and the fertilizers that are applied through a watering can, wetting the earth so that the roots absorb it. But to be really useful it is very important to follow the instructions for use , as they are highly concentrated fertilizers.
We hope this article about algae has been of interest to you.
