Living organisms: habitat. Environmental factors, their general characteristics

Under the habitat is understood the space used by living organisms for existence. Thus, the topic has a direct relation to the question of the vital activity of any being. There are four types of habitats, in addition, there are various factors that transform external influence, so they also need to be considered.

Definition

So, what is the habitat of animals? The definition appeared in the nineteenth century - in the works of the Russian physiologist Sechenov. Every living organism constantly interacts with surrounding phenomena, which it was decided to call the environment. Its role is of a dual nature. On the one hand, all life processes of organisms are connected with it directly - so animals receive food, they are influenced by climate, natural selection. On the other hand, their existence exerts no less influence on the environment, in many ways defining it. Plants maintain a balance of oxygen and shade the soil, animals make it more friable. Almost any change causes living organisms. The habitat requires a comprehensive study by anyone who wants to have an idea of biology. It is also important to know that some beings can live in different conditions. Amphibians are born in the aquatic environment, and winter and feed often on land. Beetles living in the air often need soil or water for reproduction.

Symbiosis and parasitism

Surprisingly, the habitat of animals can be limited to the organisms of other animals. So, inside the person there are all kinds of representatives of microflora, and sometimes protozoa, as well as flat or round worms. The use of another as an environment by one organism is a very common situation that was present throughout the course of evolution. There is virtually no variety of animals that do not have internal parasites. In their role are algae, amoeba, infusoria. In regard to this phenomenon, it is most important to learn to distinguish between parasitism and symbiosis. In the first case, the habitat of animals is used to harm the organism in which they are located. Parasites live exclusively at the expense of their master, without killing him. Symbiosis is a useful stay for both sides, which does not bring problems and leads exclusively to benefits.

Water

The water environment is the totality of all the oceans, seas, glaciers and continental waters of our planet, the so-called hydrosphere, besides, sometimes it also includes Antarctic snow, atmospheric fluids and those contained in organisms. It occupies more than seventy percent of the surface of the globe with a major mass in the oceans and seas. Water is an integral part of the biosphere, not only water bodies, but also air and soil. To any organism it is necessary for survival. Moreover, it is water that distinguishes the Earth from neighboring planets. In addition, she played a key role in the development of life. It accumulates organic and inorganic substances, transfers heat, forms a climate and is contained in both animal and plant cells. That is why the water environment is one of the most important.

Air

The mixture of gases, which forms the atmosphere of the Earth, plays an important role for all living organisms. The air habitat directed evolution, since oxygen forms a high metabolism, which determines the structure of the respiratory system and the water-salt metabolism system. Density, composition, humidity - all this has a serious significance for the planet. Oxygen was formed two billion years ago in the process of volcanic activity, after which its share in the air steadily increased. The modern human environment is characterized by 21% of the content of this element. An important part of it is also the ozone layer, which does not allow ultraviolet radiation to reach the Earth's surface. Without it, life on the planet could be destroyed. Now a safe human environment is under threat - the ozone layer is destroyed due to negative environmental processes. This leads to the need for conscious behavior and constant selection of the best not only for people, but also for Earth solutions.

The soil

In the earth live many organisms. The habitat is also used by plants that serve as food for most living beings of the planet. It is impossible to determine unambiguously whether the soil is a non-living entity, so it is called a biocosm body. According to the definition, it is a substance that is processed in the process of vital activity of organisms. Soil habitat consists of a solid mass, including sand, clay, muddy particles; Liquid component; Gaseous is air; Alive - this is a creature, its inhabitants, all kinds of microorganisms, invertebrates, bacteria, fungi, insects. There are five tons of such forms on each hectare of land. Soil habitat is intermediate between water and land-air, so the organisms living in it often differ in the combined type of respiration. You can meet such creatures even at an impressive depth.

Interaction of organisms and the environment

Each being is different from inanimate nature by the presence of metabolism and cellular organization. Interaction with the environment occurs constantly and must be studied in complex because of the complexity of the processes. Every organism directly depends on what is happening around. The terrestrial-air environment of a human being influences it with precipitation, soil conditions and a range of temperatures. Some of the processes are useful for the body, some are indifferent, and others are harmful. Everyone has a separate definition. For example, homeostasis is the constancy of the internal system, which distinguishes living organisms. Habitat can change, which requires adaptation - movement, growth, development. Metabolism - the metabolism, accompanied by chemical reactions, such as breathing. Chemosynthesis is the process of creating organic compounds from sulfur or nitrogen compounds. Finally, it is worth remembering the definition of ontogeny. This is a set of transformations of the organism, influenced by all factors of the habitat for the entire period of its existence.

Environmental factors

For a better understanding of biological processes, it is also necessary to study this definition. Environmental factors are a complex of environmental conditions that affect the living organism. They are subdivided according to a complex classification into several types. Adaptation to them of the body is called adaptation, and its external appearance, reflecting the factors of the environment, is called the life form.

Nutrients

This is one of the types of environmental factors that affect living organisms. The habitat contains salts and elements coming in with water and food. Biogenic ones are those that are needed in large quantities for the body. For example, it is phosphorus, important for the formation of protoplasm, and nitrogen, the basis for protein molecules. The source of the first is dead organisms and rocks, and the second - atmospheric air. The lack of phosphorus affects existence almost as sharply as the absence of water. Slightly inferior in importance to elements such as calcium, potassium, magnesium and sulfur. The first is necessary for shells and bones. Potassium provides the work of the nervous system and plant growth. Magnesium enters the molecules of chlorophyll and ribosomes, and sulfur enters the amino acids and vitamins.

Abiotic factors of the environment

There are other processes that affect living organisms. Habitat includes such factors as light, climate and the like, which are by definition abiotic. Without them, processes of respiration and photosynthesis, metabolism, seasonal flights, multiplication of many animals are impossible. First of all, light is important. It takes into account its length, intensity and duration of exposure. In relation to it, a whole classification is distinguished, which is studied by biology. Habitat, filled with light, is needed for heliophytes - meadow and steppe grass, weeds, tundra plants. The sociopaths need a shadow, they prefer to live under the canopy of the forest - these are forest grasses. Optional heliophytes can adapt to any conditions: this class includes trees, strawberries, geraniums. No less important factor is the temperature. Every organism has a certain range, comfortable for life. Water, the presence of chemicals in the soil and even fires - all this also applies to the abiotic sphere.

Biotic factors

The terrestrial-air habitat is filled with living organisms. Their interaction among themselves is a separate factor worthy of study. It is necessary to divide two important types of biotic processes. The interaction can be phytogenic. This means that plants and microorganisms that affect each other and the environment participate in the process. For example, intergrowth of roots, parasitism of vines on trees, symbiosis of legumes and bacteria living on tubers. The second type is zoogenic factors. This is the effect of animals. This includes eating, spreading seeds, damaging the bark, destroying the seedlings, thinning the plantations, transferring the diseases.

Anthropogenic factor

The water, air or terrestrial environment is always associated with human activities. People are intensively changing the world around them, greatly influencing its processes. Anthropogenic factors include each impact on organisms, the landscape or the biosphere. It can be direct, if directed at living beings: for example, incorrect hunting and fishing undermine the number of certain species. Another option is an indirect effect, when a person changes the landscape, climate, air and water conditions, and soil structure. Consciously or unconsciously, a person destroys many kinds of animals or plants, while cultivating others. So there is a new environment. There are also occasional types of impact, such as the sudden delivery of alien organisms with cargo, improper drainage of swamps, the creation of dams, the spread of pests. However, some beings die and without any human involvement, so blaming people for all environmental problems is simply unfair.

Limiting factors

Every possible influence exerted on organisms from all sides, manifests itself in varying degrees. Sometimes the key substances are those that are required in the minimum amount. Accordingly, a minimum law was developed. He suggests that the weakest link in the chain of the needs of the body is its endurance in general. Thus, if in the soil there are all elements, except one, necessary for growth - the harvest will be bad. If you add only the missing, leaving all the others in the same quantity - it will get better. If you add all the others, without correcting the shortage, no changes will occur. The missing element in such a situation will be a limiting factor. However, it is worth considering the maximum impact. He describes the law of tolerance Shelford, suggesting that there is only a certain range in which the factor can remain beneficial to the body, in excess of it, it becomes harmful. Ideal conditions are called the zone of the optimum, and deviations from the norm are called oppression. Maximums and minima of impacts are called critical points, beyond which the existence of the organism is simply impossible. The degrees of tolerance to these or those conditions are different for each living being and allow to refer them to more or less hardy varieties.