Free Essay Sample «Algae»
Algae constitute a large heterogeneous group of lower plants. They are recognized as the most numerous and those among the most important photosynthesizing organisms for the planet. The plants can be found everywhere – in the seas and oceans, in fresh waters, on damp soil, and on the bark of trees. Including 12 types and 35-40 thousand species, algae play an important role in the nature since they are the main producers of organic food and oxygen in aquatic ecosystems of the Earth. However, some algae are harmful, for example, the mass reproduction of unicellular algae in fresh water causes its flowering. The role of algae in nature and human life is enormous as they are used in different industries and as an energy source. The purpose of the current paper is to study the role of algae in both the nature and human life.
What is Algae
Algae are a vast group of photosynthetic organisms which are frequently united in a special kingdom of plants. The organisms combined into a group of algae possess a number of common features. Morphologically, the most important feature for them is the absence of multicellular bodies. Apart from that, they do not have roots, stems, and leaves. Among algae, there are unicellular, colonial, and multicellular organisms. It should be mentioned that in nature, there are micro and macro algae. The size of microalgae varies from a few thousandth fractions of a millimeter to a few millimeters. This group includes red, brown, and green algae. The size of macro algae can reach several tens of meters or so. Algae can float freely in water or are attached to the soil at the bottom of ponds and various subjects. They have more simple anatomical structure compared to higher plants, in particular, the plants do not possess a conductive (vascular) system. Thus, algae belonging to the plants are avascular plants. They never form flowers and seeds, but propagate vegetatively or with spores.
The main factos affecting the development of algae are light, temperature, water availability, and carbon sources, as well as mineral and organic substances. They are widely distributed around the globe and can be found in water, soil and on its surface, on the bark of trees, on the walls of wooden and stone buildings, and even in such inhospitable places as deserts and glaciers. This implies that algae are extremely widespread which helps them to produce about 70 percent of the air.
Benefits of Algae
Algae have many benefits for nature. Firstly, they form the basis of nutrition of herbivorous animals including crustaceans, mollusks, some fish, mammals, and others. Furthermore, algae saturate the water column and the air above it with oxygen. Some of the dead algae form sedimentary rocks, such as limestone and diatomite. They contribute the soil formation and improve soil fertility. What is more, some kinds of algae are used in food. People extract iodine, bromine, and agar-agar from them. Some drugs are manufactured from algae as well. They are used in biological purification of water and as a fertilizer. Algae have received the widespread use in some industries including food, chemical, cellulose, and textile.
A great benefit of algae consists in the fact that their biomass can be used as an energy source. The main aspect in considering the prospects of using algae as a biofuel is its ability to produce oil as a byproduct of photosynthesis. Thus, from 0.5 hectare plantation, fifteen times greater algae oil is available than peanuts or corn from the same plantation, which use in the production of biofuels is not a novelty. The first studies in this area began in the 80s, when the first surge in oil prices has forced to think about the possible energy crisis and the search for alternative fuels. According to scientific researches, sea algae are able to convert solar power into biomass that has oily properties, which after processing into biofuels is virtually identical to the equivalent of crude oil. For the productiion of biofuel from algae to be economically justified, there is a necessity to explore the possibility of an artificial production of the algal mass at the cost of not more than one US dollar per kilogram. Another aspect is the usage of carbon dioxide by algae as a product providing normal activity. This fact leads to the use of sewage and industrial waste for these purposes.
Harm of Algae
Despite numerous benefits, some algae are harmful. The uncontrolled reproduction of unicellular algae in fresh water is a cause of blooms of water. In such a way, water turns green which leads to a reduction of oxygen content in water and the growth of carbon dioxide and phenols. 50 states experience a problem of algae blooms. The plant emit in water a number of toxic substances that have an antibiotic effect. In turn, it inhibits the growth of bacteria and other algae. The development of individual groups of algae affects the development of amphibians such as frogs and newt, as well as zooplankton and fish. When withering away, some algae emit specific toxins into water that may possibly lead to some serious injuries of the gastrointestinal tract of both mammals and people, as well as to dermatitis and bronchial asthma. The accumulation of algae toxins in fish with long-term use in food results in various diseases as well. Another problem is associated with the fact that when settling on underwater parts of ships and hydraulic structures such as locks and water filters, algae prevent their normal operation.
Algae are simple plants of diverse sizes that are widely distributed on the planet and have many benefits. First of all, algae are one of the main suppliers of oxygen to the atmosphere, since they are involved in the photosynthesis process along with terrestrial plants. Apart from that, their biomass can be used as an energy source. However, there is also certain harm of algae since their blooms harm the water. Furthermore, many of the species are quite toxic.